The in vitro mimicking of bone microenvironment for the study of pathologies is a challenging field that requires the design of scaffolds with suitable morphological, structural and cytocompatible properties. During last years, 3D in vitro tumour models have been developed to reproduce mechanical, biochemical and structural bone microenvironment elements, allowing cells to behave as in vivo.

In this work, gas foamed polyether urethane foams (PUF) and 3D printed thermoplastic polyether urethane (3DP-PU) designed with different patterns are proposed as scaffolds for in vitro model of bone tissue. Surface coatings for a biomimetic behaviour of the 3D scaffold models were also investigated. Morphological, chemico-physical, mechanical properties, and biological in vitro behaviour were investigated.

PUFs for metastases investigation. The suitability of PUF as 3D in vitro model to study the interactions between bone tumour initiating cells and the bone microenvironment was investigated. PUF open porosity (>70%) appeared suitable to mimic trabecular bone structure. Human adipose derived stem cells (ADSC) were cultured and differentiated into osteoblast lineage on the PU foam, as confirmed by Alizarin Red staining and RT-PCR, thus offering a bone biomimetic microenvironment to the further co-culture with bone derived tumour-initiating cells (MCFS). Tumour aggregates were observed after three weeks of co-culture by e-cadherin staining and SEM; modification in CaP distribution was identified by SEM-EDX and associated to the presence of tumour cells.

3DP-PU as tumour bone model. 3D printed scaffolds have pores with a precise and regular geometry (0°-90°, 0°-45°-90°-135°, 0°-60°-120°). PU scaffold porosity evidenced values from 55 to 67%, values that belong to the porosity range of the trabecular bone tissue (30-90%). The compressive modulus varied between 2 and 4 MPa, depending on the printed pattern. Biomimetic nanostructured coating was performed on 0-90° 3DP-PU by Ionized Jet Deposition. Coatings had a submicrometric thickness, variable tuning deposition time, nanostructured surface morphology and biomimetic composition. Coating on 3DP-PU promoted cells colonization of the whole porous scaffolds, compared to the controls, where cells concentrated mostly on the outer layers.

In conclusion, based on the obtained results, scaffolds with different geometries have been successfully produced. Morphological and structural properties of the scaffolds here presented are suitable for mimicking the bone tissue, in order to produce a 3D in vitro model useful for bone pathologies research.

Abstract

The study of spinopelvic anatomy and movement has received great interest as these characteristics influence the biomechanical behavior (and outcome) following hip arthroplasty. However, to-date there is little knowledge of what “normal” is and how this varies with age. This study aims to determine how dynamic spino-pelvic characteristics change with age, with well-functioning hips and assess how these changes are influenced by the presence of hip arthritis.

This is an IRB-approved, cross-sectional, cohort study; 100 volunteers (asymptomatic hips, Oxford-Hip-sore>45) [age:53 ± 17 (24-87) years-old; 51% female; BMI: 28 ± 5] and 200 patients with end-stage hip arthritis [age:56 ± 19 (16-89) years-old; 55% female; BMI:28 ± 5] were studied. All participants underwent lateral spino-pelvic radiographs in the standing and deep-seated positions to determine maximum hip and spine flexion. Parameters measured included lumbar-lordosis (LL), pelvic incidence, pelvic-tilt (PT), pelvic-femoral angles (PFA). Lumbar flexion (ΔLL), hip flexion (ΔPFA) and pelvic movement (ΔPT) were calculated. The prevalence of spinopelvic imbalance (PI–LL>10?) was determined.

There were no differences in any of the spino-pelvic characteristics or movements between sexes. With advancing age, standing LL reduced and standing PT increased (no differences between groups). With advancing age, both hip (4%/decade) and lumbar (8%/decade) flexion reduced (p<0.001) (no difference between groups). ΔLL did not correlate with ΔPFA (rho=0.1). Hip arthritis was associated with a significantly reduced hip flexion (82 ±;22? vs. 90 ± 17?; p=0.003) and pelvic movements (1 ± 16? vs. 8 ± 16?; p=0.002) at all ages and increased prevalence of spinopelvic imbalance (OR:2.6; 95%CI: 1.2-5.7).

With aging, the lumbar spine loses its lumbar lordosis and flexion to a greater extent that then the hip and resultantly, the hip's relative contribution to the overall sagittal movement increases. With hip arthritis, the reduced hip flexion and the necessary compensatory increased pelvic movement is a likely contributor to the development of hip-spine syndrome and of spino-pelvic imbalance.

Aim

Diagnosing periprosthetic joint infections (PJI) can be very challenging, especially infections caused by low virulence microorganisms. No single test with a 100% accuracy is available yet. Hence, different infection definitions were introduced to improve the diagnostic confidence and quality of research articles. Due to constant developments in this field, infection definitions are adopted continuously. The aim of our study was to find the most sensitive currently available infection definition among three currently used criteria (International Consensus Meeting – criteria 2018 (ICM), Infectious Diseases Society of America - criteria 2013 (IDSA), and European Bone and Joint Infection Society – criteria 2021 (EBJIS)) for the diagnosis of PJI.

Periprosthetic joint infection (PJI) occurs in 0.2-2% of primary hip and knee arthroplasty and is a leading cause of revision surgery, impaired function, and increased morbidity and mortality. Topical, intrawound vancomycin administration allows for high local drug concentrations at the surgical site and has demonstrated good results in prevention of surgical site infection after spinal surgery. It is a promising treatment to prevent infection following hip and knee arthroplasty. Prior studies have been limited by small sample sizes and the low incidence of PJI. This systematic review and meta-analysis was performed to determine the effectiveness of topical vancomycin for the primary prevention of PJI in hip and knee arthroplasty.

A search of Embase, MEDLINE, and PubMed databases as of June 2020 was performed according to PRISMA guidelines. Studies comparing topical vancomycin to standard perioperative intravenous antibiotics in primary THA and TKA with a minimum of three months follow-up were identified. The results from applicable studies were meta-analysed to determine the impact of topical vancomycin on PJI rates as well as wound-related and overall complications. Results were expressed as odds ratios (ORs) and 95% confidence intervals

Nine comparative observational studies were eligible for inclusion. 3371 patients treated with 0.5-2g of topical vancomycin were compared to 2884 patients treated with standard care. Only one of nine studies found a significantly lower rate of PJI after primary THA or TKA (OR 0.09-1.97, p=0.04 for one study, p>0.05 for eight of nine studies), though meta-analysis showed a significant benefit, with vancomycin lowering PJI rates from 1.6% in controls to 0.7% in the experimental group (OR 0.47, p=0.02, Figure 1). Individually, only one of five studies showed a significant benefit to topical vancomycin in THA, while none of seven studies investigating PJI after TKA showed a benefit to topical vancomycin. In meta-analysis of our subgroups, there was a significant reduction in PJI with vancomycin in THA (OR 0.34, p=0.04), but there was no significant difference in PJI after TKA (OR 0.60, p = 0.13). In six studies which reported complication rates other than PJI, there were no significant differences in overall complication rates with vancomycin administration for any study individually (OR 0.48-0.94, p>0.05 for all studies), but meta-analysis found a significant difference in complications, with a 6.7% overall complication rate in controls compared to 4.8% after topical vancomycin, largely driven by a lower PJI incidence (OR 0.76, p=0.04).

Topical vancomycin is protective against PJI after hip and knee arthroplasty. No increase in wound-related or overall complication rates was found with topical vancomycin. This meta-analysis is the largest to date and includes multiple recent comparative studies while excluding other confounding interventions (such as povidone-iodine irrigation). However, included studies were predominantly retrospective and no randomized-controlled trials have been published. The limited evidence summarized here indicates topical vancomycin may be a promising modality to decrease PJI, but there is insufficient evidence to conclusively show a decrease in PJI or to demonstrate safety. A prospective, randomized-controlled trial is ongoing to better answer this question.

For any figures or tables, please contact the authors directly.

Adequate visual clarity is paramount to performing arthroscopic shoulder surgery safely, efficiently, and effectively. The addition of epinephrine in irrigation fluid, and the intravenous or local administration of tranexamic acid (TXA) have independently been reported to decrease bleeding thereby improving the surgeon's visualization during arthroscopic shoulder procedures. No study has compared the effect of systemic administered TXA, epinephrine added in the irrigation fluid or the combination of both TXA and epinephrine on visual clarity during shoulder arthroscopy with a placebo group. The purpose of this study is to determine if intravenous TXA is a safe alternative to epinephrine delivered by a pressure-controlled pump in improving arthroscopic shoulder visualization during arthroscopic procedures and whether using both TXA and epinephrine together has an additive effect in improving visualization.

The design of the study was a double-blinded, randomized controlled trial with four 1:1:1:1 parallel groups conducted at one center. Patients aged ≥18 years undergoing arthroscopic shoulder procedures including rotator cuff repair, arthroscopic biceps tenotomy/tenodesis, distal clavicle excision, subacromial decompression and labral repair by five fellowship-trained upper extremity surgeons were randomized into one of four arms: Pressure pump-controlled regular saline irrigation fluid (control), epinephrine (1ml of 1:1000) mixed in irrigation fluid (EPI), 1g intravenous TXA (TXA), and epinephrine and TXA (EPI/TXA). Visualization was rated on a 4-point Likert scale every 15 minutes with 0 indicating ‘poor’ quality and 3 indicating ‘excellent’ quality. The primary outcome measure was the unweighted mean of these ratings. Secondary outcomes included mean arterial blood pressure (MAP), surgery duration, surgery complexity, and adverse events within the first postoperative week.

One hundred and twenty-eight participants with a mean age (± SD) of 56 (± 11) years were randomized. Mean visualization quality for the control, TXA, EPI, and EPI/TXA groups were 2.1 (±0.40), 2.1 (±0.52), 2.6 (±0.37), 2.6 (±0.35), respectively. In a regression model with visual quality as the dependent variable, the presence/absence of EPI was the most significant predictor of visualization quality (R=0.525; p < 0 .001). TXA presence/absence had no effect, and there was no interaction between TXA and EPI. The addition of MAP and surgery duration strengthened the model (R=0.529; p < 0 .001). Increased MAP and surgery duration were both associated with decreased visualization quality. When surgery duration was controlled, surgery complexity was not a significant predictor of visualization quality. No adverse events were recorded in any of the groups.

Intravenous administration of TXA is not an effective alternative to epinephrine in the irrigation fluid to improve visualization during routine arthroscopic shoulder surgeries although its application is safe. There is no additional improvement in visualization when TXA is used in combination with epinephrine beyond the effect of epinephrine alone.

Recent studies on animal models focused on the effect of preserving tendon remnant of rotator cuff on tendon healing. A positive effect by combining tendon remnant preservation and small bone vents on the greater tuberosity in comparison with standard tendon-to-bone repair has been shown. The purpose of the present clinical study was to evaluate the efficacy of biologic augmentation of arthroscopic rotator cuff repair by maintaining tendon remnant on rotator cuff footprint combined with small bone vents of the greater tuberosity.

A retrospective study was conducted. All patients who underwent arthroscopic rotator cuff repair associated with small bone vents (nanofractures) and tendon footprint preservation were considered eligible for the study. Inclusion criteria were: diagnosis of full-thickness rotator cuff tear as diagnosed at preoperative magnetic resonance imaging (MRI) and confirmed at the time of surgery; minimum 24-month of follow-up and availability of post-operative MRI performed not earlier than 6 months after surgery. Exclusion criteria were: partial thickness tears, irreparable tears, capsulo-labral pathologies, calcific tendonitis, gleno-humeral osteoarthritis and/or previous surgery.

Primary outcome was the ASES score. Secondary outcomes were: Quick-DASH and WORC scores, and structural integrity of repaired tendons by magnetic resonance imaging (MRI) performed six months after surgery. A paired t-test was used to compare pre- and postoperative clinical outcomes. Subgroup analysis was performed according to tear size. Significance was set at p < 0.05.

The study included 29 patients (M:F = 15:14). Mean age (+ SD) of patients was 61.7 + 8.9 years. Mean follow-up was 27.4 ± 2.3 months. Comparison between pre- and postoperative functional scores showed significant clinical improvement (p < 0.001). Subgroup analysis for tear size showed significant differences in the QuickDASH score (0.04). Particularly, a significant difference in the QuickDASH score could be detected between medium and large tears (p=0.008) as well as medium and massive lesions (p=0.04). No differences could be detected between large and massive tears (p= 0.35). Postoperative imaging showed healed tendons in 21 out of 29 (72%) cases.

Preservation of tendon remnant combined with small bone vents in the repair of medium-to-massive full-thickness rotator cuff tears provided significant improvement in clinical outcome compared to baseline conditions with complete structural integrity in 72% of the cases.

In older patients (>75 years of age), with an intact rotator cuff, requiring a total shoulder replacement (TSR) there is, at present, uncertainty whether an anatomic TSR (aTSR) or a reverse TSR (rTSR) is best for the patient. This comparison study of same age patients aims to assess clinical and radiological outcomes of older patients (≥75 years) who received either an aTSR or a rTSA.

Consecutive patients with a minimum age of 75 years who received an aTSR (n=44) or rTSR (n=51) were prospectively studied. Pre- and postoperative clinical evaluations included the ASES score, Constant score, SPADI score, DASH score, range of motion (ROM) and pain and patient satisfaction for a follow-up of 2 years. Radiological assessment identified glenoid and humeral component osteolysis, including notching with a rTSR.

Postoperative improvement for ROM and all clinical assessment scores for both groups was found. There were significantly better patient reported outcome scores (PROMs) in the aTSR group compared with the rTSR patients (p<0.001). Both groups had only minor osteolysis on radiographs. No revisions were required in either group. The main complications were scapular stress fractures for the rTSR patients and acromioclavicular joint pain for both groups.

This study of older patients (>75 years) demonstrated that an aTSR for a judiciously selected patient with good rotator cuff muscles can lead to a better clinical outcome and less early complications than a rTSR.

Glenoid baseplate orientation in reverse shoulder arthroplasty (RSA) influences clinical outcomes, complications, and failure rates. Novel technologies have been produced to decrease performance heterogeneity of low and high-volume surgeons. This study aimed to determine novice and experienced shoulder surgeon's ability to accurately characterise glenoid component orientation in an intra-operative scenario.

Glenoid baseplates were implanted in eight fresh frozen cadavers by novice surgical trainees. Glenoid baseplate version, inclination, augment rotation, and superior-inferior centre of rotation (COR) offset were then measured using in-person visual assessments by novice and experienced shoulder surgeons immediately after implantation. Glenoid orientation parameters were then measured using 3D CT scans with digitally reconstructed radiographs (DRRs) by two independent observers. Bland-Altman plots were produced to determine the accuracy of glenoid orientation using standard intraoperative assessment compared to postoperative 3D CT scan results.

Visual assessment of glenoid baseplate orientation showed “poor” to “fair” correlation to 3D CT DRR measurements for both novice and experienced surgeon groups for all measured parameters. There was a clinically relevant, large discrepancy between intra-operative visual assessments and 3D CT DRR measurements for all parameters. Errors in visual assessment of up to 19.2 degrees of inclination and 8mm supero-inferior COR offset occurred. Experienced surgeons had greater measurement error than novices for all measured parameters.

Intra-operative measurement errors in glenoid placement may reach unacceptable clinical limits. Kinesthetic input during implantation likely improves orientation understanding and has implications for hands-on learning.

Primary hip and knee joint replacements in Canada have been estimated to cost over $1.4 billion dollars annually, with revision surgery costing $177 million. The most common cause of revision arthroplasty surgery in Canada is infection. Periprosthetic joint infections (PJIs) are a devastating though preventable complication following arthroplasty. Though variably used, antibiotic laden bone cement (ALBC) has been demonstrated to decrease PJIs following primary total knee arthroplasty (TKA). Unfortunately, ALBC is costlier than regular bone cement (RBC). Therefore, the aim of this study was to determine if the routine use of ALBC in primary TKA surgery is a cost-effective practice from the perspective of the Canadian healthcare system.

A decision tree was constructed using a decision analysis software (TreeAge Software, Williamstown, Massachusetts) to a two-year time horizon comparing primary TKA with either ALBC or RBC from the perspective of a single-payer healthcare system. All costs were in 2020 Canadian dollars. Health utilities were in the form of quality adjusted life years (QALYs). Model inputs for cost were derived from regional and national databases. Health utilities and probability parameters were derived from the latest literature. One-way deterministic sensitivity analysis was performed on all model parameters. The primary outcome of this analysis was an incremental cost-effectiveness ratio (ICER) with a willingness-to-pay (WTP) threshold of $50,000 per QALY.

Primary TKA with ALBC (TKA-ALBC) was found to be more cost-effective compared to primary TKA with RBC (TKA-RBC). More specifically, TKA-ALBC dominated TKA-RBC as it was less costly on the long term ($11,160 vs. $11,118), while providing the same QALY (1.66). The ICER of this cost-utility analysis (CUA) was $-11,049.72 per QALY, much less than the WTP threshold of $50,000 per QALY. The model was sensitive to costs of ALBC-TKA as well as the probability of PJI following ALBC-TKA and RBC-TKA. ALBC ceased to be cost effective once the cost of ALBC was greater than $223.08 CAD per bag of cement.

The routine use of ALBC in primary TKA is a cost-effective practice in the context of the Canadian healthcare system as long as the cost of ALBC is maintained at a reasonable price and the published studies to-date keep supporting the efficacy of ALBC in decreasing PJI following primary TKA. Further, this analysis is very conservative, and ALBC is likely much more cost-effective than presented. This is due to this model's revision surgery cost parameter being based on the average cost of all revision TKA surgery in Canada, regardless of etiology. Considering many PJIs require two-stage revisions, the cost parameter used in this analysis for revision surgery is an underestimate of true cost. Ultimately, this is the first cost-effectiveness study evaluating this topic from the perspective of the Canadian healthcare system and can inform future national guidelines on the subject matter.

Abstract

Our knowledge of primary bone marrow edema (BME) of the knee is still limited. A major contributing factor is that it shares several radiological findings with a number of vascular, traumatic, and inflammatory conditions having different histopathological features and etiologies.

BME can be primary or secondary. The most commonly associated conditions are osteonecrosis, osteochondritis dissecans, complex regional pain syndrome, mechanical strain such as bone contusion/bruising, micro-fracture, stress fracture, osteoarthritis, and tumor. The etiology and pathogenesis of primary BME are unclear. Conservative treatment includes analgesics, non-steroidal anti-inflammatory drugs, weight-bearing limitations, physiotherapy, pulsed electromagnetic fields, prostacyclin, and bisphosphonates. Surgical treatment, with simple perforation, fragment stabilization, combined scraping and perforation, and eventually osteochondral or chondrocyte transplant, is reserved for the late stages. This retrospective study of a cohort of patients with primary BME of the knee was undertaken to describe their clinical and demographic characteristics, identify possible risk factors, and assess treatment outcomes.

We reviewed the records of 48 patients with primary BME of the knee diagnosed on MRI by two radiologists and two orthopedists. History, medications, pain type, leisure activities, smoking habits, allergies, and environmental factors were examined. Analysis of patients’ characteristics highlighted that slightly overweight middle-aged female smokers with a sedentary lifestyle are the typical patients with primary BME of the knee. In all patients, the chief symptom was intractable day and night pain (mean value, 8.5/10 on the numerical rating scale) with active as well as passive movement, regardless of BME extent. Half of the patients suffered from thyroid disorders; indeed, the probability of having a thyroid disorder was higher in our patients than in two unselected groups of patients, one referred to our orthopedic center (odds ratio, 18.5) and another suffering from no knee conditions (odds ratio, 9.8). Before pain onset, 56.3% of our cohort had experienced a stressful event (mourning, dismissal from work, concern related to the COVID-19 pandemic). After conservative treatment, despite the clinical improvement and edema resolution on MRI, 93.8% of patients described two new symptoms: a burning sensation in the region of the former edema and a reduced ipsilateral patellar reflex. These data suggest that even though the primary BME did resolve on MRI, the knee did not achieve full healing.

Abstract

Rotator cuff repair has excellent clinical outcomes but continues to be a challenge when it comes to large and massive tears as well as revision procedures. Reported symptomatic retear rates are still too high to be acceptable. The purpose of the present study was to evaluate the effectiveness of a combination of augmentation techniques consisting of microfractures of the greater tuberosity, extracellular matrix (ECM) patch graft and subsequent platelet concentrate (PC) subacromial injections in revision rotator cuff repair.

The study was designed as a retrospective comparative study on prospectively collected data from a consecutive cohort of patients. All patients who underwent arthroscopic revision rotator cuff repair for symptomatic failure of previous posterosuperior rotator cuff repair were considered eligible for the study. Symptomatic failure had been diagnosed according to clinical examination and confirmed by magnetic resonance imaging (MRI). Structural integrity had been assessed on MRI and classified according to Sugaya classification. Only patients affected by stage IV-V were considered eligible. Tear reparability was confirmed during arthroscopy. Only patients with a minimum 2 years follow-up were included. Patients were divided in two groups. In group 1 (control group) a standard arthroscopic revision and microfractures of the greater tuberosity were performed; in group 2 (experimental group), microfractures of the greater tuberosity and a ECM patch graft were used to enhance tendon repair, followed by postoperative PC injections. Minimum follow-up was 12 months. Primary outcome was the Constant-Murley score (CMS) normalized for age and gender. Subjective outcome was assessed with the Disabilities of the Arm, Shoulder and Hand (DASH) score in its short version (Quick-DASH). Tendon integrity was assessed with MRI at 6 months after surgery. Comparison between groups for all discrete variables at baseline and at follow-up was carried out with the Student's t-test for normally distributed data, otherwise Mann-Whitney U-test was used. Within-group differences (baseline vs follow-up) for discrete variables were analyzed by paired t-test, or by Wilcoxon signed-rank test in case of data with non-normal distribution. Differences for categorical variables were assessed by chi-squared test. Significance was considered for p values < 0.05.

Forty patients were included in the study (20 patients for each group). The mean follow-up was 13 ± 1.6 months. No patients were lost at the follow up. Comparison between groups did not show significant differences for baseline characteristics. At follow-up, mean CMS was 80.7 ± 16.6 points in group 1 and 91.5 ± 11.5 points in group 2 (p= 0.022). Mean DASH score was 28.6 ± 21.6 points in group 1 and 20.1 ± 17.4 points in group 2 (p= 0.178). Post-operative MRI showed 6 healed shoulders in Group 1 and 16 healed shoulders in Group 2 (p<0.004). No postoperative complications were reported in both groups.

The combination of microfractures of the greater tuberosity, ECM patch graft, and subsequent PC subacromial injections is an effective strategy in improving tendon healing rate.

The purpose of this prospective pilot study is to examine the feasibility of a physiotherapist led rapid access shoulder screening clinic (RASC). The goal of this study is to assess for improvements in patient access to care, patient reported outcome measures, patient reported experience measures, and cost outcomes using time driven activity based costing methods.

Patient recruitment began in January 2021. Consultation requests from general practitioners and emergency rooms are analyzed and triaged through a central system. One half of patients awaiting consultation were triaged to the traditional route used at our center while the other half were triaged to be assessed at the RASC. Outcome measures consisting of the Simple Shoulder Test and SF-12 were recorded at the initial consultation and at follow up appointments. Cost benefit analysis was conducted using time driven activity based costing methods (TD-ABC).

From January to August of 2021, 123 new patients were triaged for RASC assessment. On average, the RASC gets 10 new referrals per month. As of September 2021, there are 65 patients still on waitlist for RASC assessment with 58 having been assessed. Of the 58, 11% were discharged through the RASC, 48% pursued private physiotherapy, 14% had injections, 19% proceeded on for surgical consultation, and 8% did not show. Over time same time period, approximately 15 new patients were seen in consultation by the surgeon's office.

Thirty-five responses were obtained from RASC patients during their initial intake assessment. The average age of respondents was 54.7 with 21 females and 14 males. Median SF-12 scores in the physical dimension (PCS-12) for RASC patients were 36.82 and mental (MCS-12) 49.38927. Median Simple Shoulder Test scores measured 6. Of the patients who responded to the follow up questionnaires after completing physiotherapy at the RASC, both the SF-12 and Simple Shoulder Test scoring improved. Median PCS-12 measured 47.08, MCS-12 of 55.87, and Simple Shoulder Test measured 8.

RASC assessments by PT saved $172.91 per hour for consultation and $157.97 per hour for patient follow ups.

Utilization of a physiotherapy led rapid access shoulder clinic resulted in improvements in patient outcomes as measured by the SF-12 and Simple Shoulder Test as well as significant direct cost savings. Proper triage protocols to identify which patients would be suitable for RASC assessment, buy-in from physiotherapists, and timely assessment of patients for early initiation of rehabilitation for shoulder pain is paramount to the success of a RASC system at our centre. Future research direction would be geared to analyzing a larger dataset as it becomes available.

Aim

The aim of this study was to investigate the metabolomic profile of synovial fluid in periprosthetic joint infection (PJI) cases regarding a possible diagnostic approach. Also, further information about the metabolic composition of synovial fluid in PJI may point to future diagnostic and therapeutic approaches.

Aim

Treatment recommendations for periprosthetic joint infections (PJI) include surgical debridement, antibiotic therapy or staged revision. In surgical related foot and ankle infections (SR-FAI), implant removal will lead to instability. Debridement is difficult because the implant is outside the joint. Recommendations regarding PJI treatment can therefore not be extrapolated to the treatment of SR-FAI.

Aim

Magnetic resonance imaging (MRI) and 2-[¹⁸F]-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) Positron Emission Tomography, paired with Computed Tomography (PET/CT) are two indicated advanced imaging modalities in the complicated diagnostic work-up of osteomyelitis. PET/MRI is a relatively novel hybrid modality with suggested applications in musculoskeletal infection imaging. The goal of this study was to assess the value of hybrid ¹⁸F-FDG PET/MRI for chronic osteomyelitis diagnosis and surgical planning.

Aim

Acute hematogenous periprosthetic joint infection (AHI) is a diagnosis on the rise. The management is challenging and the optimum treatment is not clearly defined. The purpose of this study was to evaluate the characteristics of AHI, and to study risk factors affecting treatment outcome.

One in five patients remain unsatisfied due to ongoing pain and impaired mobility following total knee arthroplasty (TKA). It is important if surgeons can pre-operatively identify which patients may be at risk for poor outcomes after TKA. The purpose of this study was to determine if there is an association between pre-operative measures and post-operative outcomes in patients who underwent TKA.

This study included 28 patients (female = 12 / male = 16, age = 63.6 ± 6.9, BMI = 29.9 ± 7.4 kg/m2) with knee osteoarthritis who were scheduled to undergo TKA. All surgeries were performed by the same surgeon (GD), and a subvastus approach was performed for all patients. Patients visited the gait lab within one-month of surgery and 12 months following surgery. At the gait lab, patients completed the knee injury and osteoarthritis outcome score (KOOS), a timed up and go (TUG), and walking task. Variables of interest included the five KOOS sub-scores (symptoms, pain, activities of daily living, sport & recreation, and quality of life), completion time for the TUG, walking speed, and peak knee biomechanics variables (flexion angle, abduction moment, power absorption). A Pearson's product-moment correlation was run to assess the relationship between pre-operative measures and post-operative outcomes in the TKA patients.

Preliminary analyses showed the relationship to be linear with all variables normally distributed, as assessed by Shapiro-Wilk's test (p > .05), and there were no outliers. There were no statistically significant correlations between any of the pre-operative KOOS sub-scores and any of the post-operative biomechanical outcomes. Pre-operative TUG time had a statistically significant, moderate positive correlation with post-operative peak knee abduction moments [r(14) = .597, p < .001] and peak knee power absorption [r(14) = .498, p = .007], with pre-operative TUG time explaining 36% of the variability in peak knee abduction moment and 25% of the variability in peak knee power absorption. Pre-operative walking speed had a statistically significant, moderate negative correlation with post-operative peak knee abduction moments [r(14) = -.558, p = .002] and peak knee power absorption [r(14) = -.548, p = .003], with pre-operative walking speed explaining 31% of the variability in peak knee abduction moment and 30% of the variability in peak knee power absorption.

Patient reported outcome measures (PROMs), such as the KOOS, do indicate the TKA is generally successful at relieving pain and show an overall improvement. However, their pre-operative values do not correlate with any biomechanical indicators of post-operative success, such as peak knee abduction moment and knee power. Shorter pre-operative TUG times and faster pre-operative walking speeds were correlated with improved post-operative biomechanical outcomes. These are simple tasks surgeons can implement into their clinics to evaluate their patients. Future research should expand these findings to a larger sample size and to determine if other factors, such as surgical approach or implant design, improves patient outcomes.

Aims

Despite numerous studies on periprosthetic joint infections (PJI), there are no robust data on the risk factors and timing of metachronous infections. This study was performed to answer the following questions: 1) Is there any difference of manifestation time of metachronous PJIs between different localizations of multiple artificial joints? 2) Can we identify any specific risk factor for metachronous PJIs for different localizations of multiple artificial joints?

Bone metastases radiographically appear as regions with high (i.e. blastic metastases) or low (i.e. lytic metastases) bone mineral density. The clinical assessment of metastatic features is based on computed tomography (CT) but it is still unclear if the actual size of the metastases can be accurately detected from the CT images and if the microstructure in regions surrounding the metastases is altered (Nägele et al., 2004, Calc Tiss Int). This study aims to evaluate (i) the capability of the CT in evaluating the metastases size and (ii) if metastases affect the bone microstructure around them.

Ten spine segments consisted of a vertebra with lytic or mixed metastases and an adjacent control (radiologically healthy) were obtained through an ethically approved donation program. The specimens were scanned with a clinical CT (AquilionOne, Toshiba: slice thickness:1mm, in-plane resolution:0.45mm) to assess clinical metastatic features and a micro-CT (VivaCT80, Scanco, isotropic voxel size:0.039mm) to evaluate the detailed microstructure. The volume of the metastases was measured from both CT and micro-CT images (Palanca et al., 2021, Bone) and compared with a linear regression. The microstructural alteration around the metastases was evaluated in the volume of interest (VOI) defined in the micro-CT images as the volume of the vertebral body excluding the metastases. Three 3D microstructural parameters were calculated in the VOI (CTAn, Bruker SkyScan): Bone Volume Fraction (BV/TV), Trabecular Thickness (Tb.Th.), Trabecular Spacing (Tb.Sp.). Medians of each parameter were compared (Kruskal-Wallis, p=0.05).

One specimen was excluded as it was not possible to define the size of the metastases in the CT scans. A strong correlation between the volume obtained from the CT and micro-CT images was found (R2=0.91, Slope=0.97, Intercept=2.55, RMSE=5.7%, MaxError=13.12%). The differences in BV/TV, Tb.Th. and Tb.Sp. among vertebrae with lytic and mixed metastases and control vertebrae were not statistically significant (p-value>0.6). Similar median values of BV/TV were found in vertebrae with lytic (13.2±2.4%) and mixed (12.8±9.8%) metastases, and in controls (13.0±10.1%). The median Tb.Th. was 176±18 ∓m, 179±43 ∓m and 167±91 ∓m in vertebrae with lytic and mixed metastases and control vertebrae, respectively. The median Tb. Sp. was 846±26 ∓m, 849±286 ∓m and 880±116 ∓m in vertebrae with lytic and mixed metastases and control vertebrae, respectively.

In conclusion, the size of vertebral metastases can be accurately assess using CT images. The 3D microstructural parameters measured were comparable with those reported in the literature for healthy vertebrae (Nägele et al., 2004, Calc Tiss Int, Sone et al., 2004, Bone) and showed how the microstructure of the bone tissue surrounding the lesion is not altered by the metastases.

Abstract

Background

Bacteriophages are natural viruses of interest in the field of PJI. A paper previously reported the PhagoDAIR procedure (use of phages during DAIR) in three patients with PJI for whom explantation was not desirable. As the need to isolate the pathogen before surgery to perform phage susceptibility testing is a strong hindrance for the development of this procedure, we developed post-operative phage injections using ultrasound, in patients infected with S. aureus and/or P. aeruginosa who were eligible for the PhagoDAIR procedure, but for whom phages were not available at the time of surgery.

Abstract

Breast cancer is the most frequent malignancy in women with an estimation of 2.1 million new diagnoses in 2018. Even though primary tumours are usually efficiently removed by surgery, 20–40% of patients will develop metastases in distant organs. Bone is one of the most frequent site of metastases from advanced breast cancer, accounting from 55 to 58% of all metastases. Currently, none of the therapeutic strategies used to manage breast cancer bone metastasis are really curative. Tailoring a suitable model to study and evaluate the disease pathophysiology and novel advanced therapies is one of the major challenges that will predict more effectively and efficiently the clinical response. Preclinical traditional models have been largely used as they can provide standardization and simplicity, moreover, further advancements have been made with 3D cultures, by spheroids and artificial matrices, patient derived xenografts and microfluidics. Despite these models recapitulate numerous aspects of tumour complexity, they do not completely mimic the clinical native microenvironment. Thus, to fulfil this need, in our study we developed a new, advanced and alternative model of human breast cancer bone metastasis as potential biologic assay for cancer research. The study involved breast cancer bone metastasis samples obtained from three female patients undergoing wide spinal decompression and stabilization through a posterior approach. Samples were cultured in a TubeSpin Bioreactor on a rolling apparatus under hypoxic conditions at time 0 and for up to 40 days and evaluated for viability by the Alamar Blue test, gene expression profile, histology and immunohistochemistry. Results showed the maintenance and preservation, at time 0 and after 40 days of culture, of the tissue viability, biological activity, as well as molecular markers, i.e. several key genes involved in the complex interactions between the tumour cells and bone able to drive cancer progression, cancer aggressiveness and metastasis to bone. A good tis sue morphological and microarchitectural preservation with the presence of lacunar osteolysis, fragmented trabeculae locally surrounded by osteoclast cells and malignant cells and an intense infiltration by tumour cells in bone marrow compartment in all examined samples. Histomorphometrical data on the levels of bone resorption and bone apposition parameters remained constant between T0 and T40 for all analysed patients. Additionally, immunohistochemistry showed homogeneous expression and location of CDH1, CDH2, KRT8, KRT18, Ki67, CASP3, ESR1, CD8 and CD68 between T0 and T40, thus further confirming the invasive behaviour of breast cancer cells and indicating the maintaining of the metastatic microenvironment. The novel tissue culture, set-up in this study, has significant advantages in comparison to the pre-existent 3D models: the tumour environment is the same of the clinical scenario, including all cell types as well as the native extracellular matrix; it can be quickly set-up employing only small samples of breast cancer bone metastasis tissue in a simple, ethically correct and cost-effective manner; it bypasses and/or decreases the necessity to use more complex preclinical model, thus reducing the ethical burden following the guiding principles aimed at replacing/reducing/refining (3R) animal use and their suffering for scientific purposes; it can allow the study of the interactions within the breast cancer bone metastasis tissue over a relatively long period of up to 40 days, preserving the tumour morphology and architecture and allowing also the evaluation of different biological factors, parameters and activities. Therefore, the study provides for the first time the feasibility and rationale for the use of a human-derived advanced alternative model for cancer research and testing of drugs and innovative strategies, taking into account patient individual characteristics and specific tumour subtypes so predicting patient specific responses.

Abstract

The Banff Patellofemoral Instability Instrument 2.0 (BPII 2.0) is a patient-reported disease-specific quality of life (QOL) outcome measure used to assess patients with recurrent lateral patellofemoral instability (LPI) both pre- and post-operatively. The purpose of this study was to compare the BPII 2.0 to four other relevant patient reported outcome measures (PROMs): the Tampa Scale-11 for kinesiophobia (TSK-11), the pain catastrophizing scale (PCS), a general QOL (EQ-5D-5L), and a return to sport index (ACL-RSI). This concurrent validation sought to compare and correlate the BPII 2.0 with these other measures of physical, psychological, and emotional health. The psychological and emotional status of patients can impact recovery and rehabilitation, and therefore a disease-specific PROM may be unable to consistently identify patients who would benefit from interventions encompassing a holistic and person-focused approach in addition to disease-specific treatment.

One hundred and ten patients with recurrent lateral patellofemoral instability (LPI) were assessed at a tertiary orthopaedic practice between January and October 2021. Patients were consented into the study and asked to complete five questionnaires: the BPII 2.0, TSK-11, PCS, EQ-5D-5L, and the ACL-RSI at their initial orthopaedic consultation. Descriptive demographic statistics were collected for all patients. A Pearson's r correlation coefficient was employed to examine the relationships between the five PROMs. These analyses were computed using SPSS 28.0 © (IBM Corporation, 2021).

One hundred and ten patients with a mean age of 25.7 (SD = 9.8) completed the five PROMs. There were 29 males (26.3%) and 81 females (73.6%) involving 50% symptomatic left knees and 50% symptomatic right knees. The mean age of the first dislocation was 15.4 years (SD = 7.3; 1-6) and the mean BMI was 26.5 (SD = 7.3; range = 12.5-52.6) The results of the Pearson's r correlation coefficient demonstrated that the BPII 2.0 was statistically significantly related to all of the assessed PROM's (p

There was significant correlation evident between the BPII 2.0 and the four other PROMs assessed in this study. The BPII 2.0 does not explicitly measure kinesiophobia or pain catastrophizing, however, the significant statistical relationship of the TSK-11 and PCS to the BPII 2.0 suggests that this information is being captured and reflected. The preliminary results of this concurrent validation suggest that the pre-operative data may offer predictive validity. Future research will explore the ability of the BPII 2.0 to predict patient quality of life following surgery.

Abstract

Vertebral metastases are the most common type of malignant lesions of the spine. Although this tumour is still considered incurable and standard treatments are mainly palliative, the standard approach consists in surgical resection, which results in the formation of bone gaps. Hence, scaffolds, cements and/or implants are needed to fill the bone lacunae.

Here, we propose a novel approach to address spinal metastases recurrence, based on the use of anti-tumour metallic-based nanostructured coatings. Moreover, for the first time, a gradient microfluidic approach is proposed for the screening of nanostructured coatings having anti-tumoral effect, to determine the optimal concentration of the metallic compound that permits selective toxicity towards tumoral cells.

Coatings are based on Zinc as anti-tumour agent, which had been never explored before for treatment of bone metastases.

The customized gradient generating microfluidic chip was designed by Autodesk Inventor and fabricated from a microstructured mould by using replica moulding technique. Microstructured mould were obtained by micro-milling technique. The chip is composed of a system of microfluidic channels generating a gradient of 6 concentrations of drug and a compartment with multiple arrays of cell culture chambers, one for each drug concentration. The device is suitable for dynamic cultures and in-chip biological assays. The formation of a gradient was validated using a methylene blue solution and the cell loading was successful.

Preliminary biological data on 3D dynamic cultures of stromal cells (bone-marrow mesenchymal stem cells) and breast carcinoma cells (MDA-MB-231) were performed in a commercial microfluidic device.

Results showed that Zn eluates had a selective cytotoxic effect for tumoral cells. Indeed, cell migration and cell replication of treated tumoral cells was inhibited. Moreover, the three-dimensionality of the model strongly affected the efficacy of Zn eluates, as 2D preliminary experiments showed a high cytotoxic effect of Zn also for stromal cells, thus confirming that traditional screening tests on 2D cultured cells usually lead to an overestimation of drug efficacy and toxicity.

Based on preliminary data, the customized platform could be considered a major advancement in cancer drug screenings as it also allows the rapid and efficient screening of biomaterials having antitumor effect.

Abstract

Aim

Our aim was to evaluate the prevalence and impact of unexpected intraoperative cultures on the outcome of total presumed aseptic knee and hip revision surgery.

With the rising rates, and associated costs, of total knee arthroplasty (TKA), enhanced clarity regarding patient appropriateness for TKA is warranted. Towards addressing this gap, we elucidated in qualitative research that surgeons and osteoarthritis (OA) patients considered TKA need, readiness/willingness, health status, and expectations of TKA most important in determining patient appropriateness for TKA. The current study evaluated the predictive validity of pre-TKA measures of these appropriateness domains for attainment of a good TKA outcome.

This prospective cohort study recruited knee OA patients aged 30+ years referred for TKA at two hip/knee surgery centers in Alberta, Canada. Those receiving primary, unilateral TKA completed questionnaires pre-TKA assessing TKA need (WOMAC-pain, ICOAP-pain, NRS-pain, KOOS-physical function, Perceived Arthritis Coping Efficacy, prior OA treatment), TKA readiness/willingness (Patient Acceptable Symptom State (PASS), willingness to undergo TKA), health status (PHQ-8, BMI, MSK and non-MSK comorbidities), TKA expectations (HSS KR Expectations survey items) and contextual factors (e.g., age, gender, employment status). One-year post-TKA, we assessed for a ‘good outcome’ (yes/no), defined as improved knee symptoms (OARSI-OMERACT responder criteria) AND overall satisfaction with TKA results. Multiple logistic regression, stepwise variable selection, and best possible subsets regression was used to identify the model with the smallest number of independent variables and greatest discriminant validity for our outcome. Receiver Operating Characteristic (ROC) curves were generated to compare the discriminative ability of each appropriateness domain based on the ‘area under the ROC curve’ (AUC). Multivariable robust Poisson regression was used to assess the relationship of the variables to achievement of a good outcome.

f 1,275 TKA recipients, 1,053 (82.6%) had complete data for analyses (mean age 66.9 years [SD 8.8]; 58.6% female). Mean WOMAC pain and KOOS-PS scores were 11.5/20 (SD 3.5) and 52.8/100 (SD 17.1), respectively. 78.1% (95% CI 75.4–80.5%) achieved a good outcome. Stepwise variable selection identified optimal discrimination was achieved with 13 variables. The three best 13-variable models included measures of TKA need (WOMAC pain, KOOS-PS), readiness/willingness (PASS, TKA willingness), health status (PHQ-8, troublesome hips, contralateral knee, low back), TKA expectations (the importance of improved psychological well-being, ability to go up stairs, kneel, and participate in recreational activities as TKA outcomes), and patient age. Model discrimination was fair for TKA need (AUC 0.68, 95% CI 0.63-0.72), TKA readiness/willingness (AUC 0.61, 95% CI 0.57-0.65), health status (AUC 0.59, 95% CI 0.54-0.63) and TKA expectations (AUC 0.58, 95% CI 0.54-0.62), but the model with all appropriateness variables had good discrimination (AUC 0.72, 95% CI 0.685-0.76). The likelihood of achieving a good outcome was significantly higher for those with greater knee pain, disability, unacceptable knee symptoms, definite willingness to undergo TKA, less depression who considered improved ability to perform recreational activities or climb stairs ‘very important’ TKA outcomes, and lower in those who considered it important that TKA improve psychological wellbeing or ability to kneel.

Beyond surgical need (OA symptoms) and health status, assessment of patients’ readiness and willingness to undergo, and their expectations for, TKA, should be incorporated into assessment of patient appropriateness for surgery.

Prosthetic joint infections represent complications connected to the implantation of biomedical devices. Bacterial biofilm is one of the main issues causing infections from contaminated orthopaedic prostheses. Biofilm is a structured community of microbial cells that are firmly attached to a surface and have unique metabolic and physiological attributes that induce improved resistance to environmental stresses including toxic compounds like antimicrobial molecules (e.g. antibiotics). Therefore, there is increasing need to develop methods/treatments exerting antibacterial activities not only against planktonic (suspended) cells but also against adherent cells of pathogenic microorganisms forming biofilms. In this context, metal-based coatings with antibacterial activities have been widely investigated and used in the clinical practice. However, traditional coatings exhibit some drawbacks related to the insufficient adhesion to the substrate, scarce uniformity and scarce control over the toxic metal release reducing the biofilm formation prevention efficacy. Additionally, standardized and systematic approaches to test antibacterial activity of newly developed coatings are still missing, while standard microbiological tests (e.g. soft-agar assays) are typically used that are limited in terms of simultaneous conditions that can be tested, potentially leading to scarce reproducibility and reliability of the results.

In this work, we combined the Calgary Biofilm Device (CBD) as a device for high-throughput screening, together with a novel plasma-assisted technique named Ionized Jet Deposition (IJD), to generate and test new generation of nanostructured silver- and zinc-based films as coatings for biomedical devices with antibacterial and antibiofilm properties. During the experiments we tested both planktonic and biofilm growth of four bacterial strains, two gram-positive and two gram-negative bacterial strains, i.e. Staphylococcus aureus ATCC 6538P, Enterococcus faecalis DP1122 and Escherichia coli ATCC 8739 and Pseudomonas aeruginosa PAO1, respectively. The use of CBD that had the only wells covered with the metal coatings while the biofilm supports (pegs) were not sheltered allowed to selectively define the toxic effect of the metal release (from the coating) against biofilm development in addition to the toxic activity exerted by contact killing mechanism (on biofilms formed on the coating). The results indicated that the antibacterial and antibiofilm effects of the metal coatings was at least partly gram staining dependent. Indeed, Gram negative bacterial strains showed high sensitivity toward silver in both planktonic growth and biofilm formation, whereas zinc coatings provided a significant inhibitory activity against Gram positive bacterial strains. Furthermore, the coatings showed the maximal activity against biofilms directly forming on them, although, Zn coating showed a strong effect against biofilms of gram-positive bacteria also formed on uncoated pegs.

We conclude that the metal-based coatings newly developed and screened in this work are efficient against bacterial growth and adherence opening possible future applications for orthopedic protheses manufacturing.

Thoracic hyperkyphosis (TH – Cobb angle >40°) is correlated with rotator cuff arthropathy and associated with anterior tilting and protraction of scapula, impacting the glenoid orientation and the surrounding musculature. Reverse total shoulder arthroplasty (RTSA) is a reliable surgical treatment for patients with rotator cuff arthropathy and recent literature suggests that patients with TH may have comparable range of motion after RTSA. However, there exists no study reporting the possible link between patient-reported outcomes, humeral retroversion and TH after RTSA. While the risk of post-operative complications such as instability, hardware loosening, scapular notching, and prosthetic infection are low, we hypothesize that it is critical to optimize the biomechanical parameters through proper implant positioning and understanding patient-specific scapular and thoracic anatomy to improve surgical outcomes in this subset of patients with TH.

Patients treated with primary RTSA at an academic hospital in 2018 were reviewed for a two-year follow-up. Exclusion criteria were as follows: no pre-existing chest radiographs for Cobb angle measurement, change in post-operative functional status as a result of trauma or medical comorbidities, and missing component placement and parameter information in the operative note. As most patients did not have a pre-operative chest radiograph, only seven patients with a Cobb angle equal to or greater than 40° were eligible. Chart reviews were completed to determine indications for RTSA, hardware positioning parameters such as inferior tilting, humeral stem retroversion, glenosphere size/location, and baseplate size. Clinical data following surgery included review of radiographs and complications. Follow-up in all patients were to a period of two years. The American Shoulder and Elbow Surgeons (ASES) Shoulder Score was used for patient-reported functional and pain outcomes.

The average age of the patients at the time of RTSA was 71 years old, with six female patients and one male patient. The indication for RTSA was primarily rotator cuff arthropathy. Possible correlation between Cobb angle and humeral retroversion was noted, whereby, Cobb angle greater than 40° matched with humeral retroversion greater than 30°, and resulted in significantly higher ASES scores. Two patients with mean Cobb angle of 50° and mean humeral retroversion 37.5° had mean ASES scores of 92.5. Five patients who received mean humeral retroversion of 30° had mean lower ASES scores of 63.7 (p < 0 .05). There was no significant correlation with glenosphere size or position, baseplate size, degree of inferior tilting or lateralization.

Patient-reported outcomes have not been reported in RTSA patients with TH. In this case series, we observed that humeral stem retroversion greater than 30° may be correlated with less post-operative pain and greater patient satisfaction in patients with TH. Further clinical studies are needed to understanding the biomechanical relationship between RTSA, humeral retroversion and TH to optimize patient outcomes.

Postoperative surgical site infection in patients treated with lumbosacral fusion has been believed to be caused by perioperative contamination (Perioperative Inside-Out infections) in patients with comorbidities. With the proximity of these incisions to the perianal region and limited patient mobility in the early post-operative period, local contamination from gastrointestinal and/or urogenital flora (Postoperative Outside-In infections) should be considered as a major source of complication.

A single center, retrospective review of adult patients treated with open posterior lumbosacral fusions between January 2014 and January 2021. We aimed to identify common factors in patients experiencing deep postoperative infections. Oncological, minimally invasive, primary infection, and index procedures carried out at other institutions were excluded.

We identified 489 eligible patients, 20 of which required debridement deep to the fascia (4.1%). Mean age (62.9 vs 60.8), operative time (420 vs 390 minutes), estimated blood loss (1772 vs 1790 mL) and median levels fused (8.5 vs 9) were similar between the infected and non-infected groups. There was a higher percentage of deformity patients (75% vs 29%) and increased BMI (32.7 vs 28.4) in the infected group. The mean time from primary procedure to debridement was 40.8 days. Four patients showed no growth on culture. Three showed Staphylococcus species (Perioperative Inside-Out infections) requiring debridement at a mean of 100.3 days (95%CI 0- 225 days). Thirteen patients showed infection with intestinal or urogenital pathogens (Postoperative Outside-In infections) requiring debridement at a mean of 20.0 days (95%CI 9-31 days). Postoperative Outside-In infections led to debridement 80.3 days earlier than Perioperative Inside-Out infections (p= 0.007).

In this series, 65% of deep infections were due to early local contamination by gastrointestinal and/or urogenital tracts pathogens. These infections were debrided significantly earlier than the Staphylococcus species infections. Due to the proximity of the incisions to the perianal region, there should be increased focus on post-operative local wound management to ensure these pathogens are away from the wound during the critical stages of wound healing.

Abstract

Abstract:

Abstract

In multilevel posterior cervical instrumented fusions, extending the fusion across the cervico-thoracic junction at T1 or T2 (CTJ) has been associated with decreased rate of re-operation and pseudarthrosis but with longer surgical time and increased blood loss. The impact on patient reported outcomes (PROs) remains unclear. The primary objective was to determine whether extending the fusion through the CTJ influenced PROs at 3 and 12 months after surgery. Secondary objectives were to compare the number of patients reaching the minimally clinically important difference (MCID) for the PROs and mJOA, operative time duration, intra-operative blood loss (IOBL), length of stay (LOS), discharge disposition, adverse events (AEs), re-operation within 12 months of the surgery, and patient satisfaction.

This is a retrospective analysis of prospectively collected data from a multicenter observational cohort study of patients with degenerative cervical myelopathy. Patients who underwent a posterior instrumented fusion of 4 levels of greater (between C2-T2) between January 2015 and October 2020 with 12 months follow-up were included. PROS (NDI, EQ5D, SF-12 PCS and MCS, NRS arm and neck pain) and mJOA were compared using ANCOVA, adjusted for baseline differences. Patient demographics, comorbidities and surgical details were abstracted. Percentafe of patient reaching MCID for these outcomes was compared using chi-square test. Operative duration, IOBL, AEs, re-operation, discharge disposittion, LOS and satisfaction were compared using chi-square test for categorical variables and independent samples t-tests for continuous variables.

A total of 206 patients were included in this study (105 patients not crossing the CTJ and 101 crossing the CTJ). Patients who underwent a construct extending through the CTJ were more likely to be female and had worse baseline EQ5D and NDI scores (p> 0.05). When adjusted for baseline difference, there was no statistically significant difference between the two groups for the PROs and mJOA at 3 and 12 months. Surgical duration was longer (p 0.05). Satisfaction with the surgery was high in both groups but significantly different at 12 months (80% versus 72%, p= 0.042 for the group not crossing the CTJ and the group crossing the CTJ, respectively). The percentage of patients reaching MCID for the NDI score was 55% in the non-crossing group versus 69% in the group extending through the CTJ (p= 0.06).

Up to 12 months after the surgery, there was no statistically significant differences in PROs between posterior construct extended to or not extended to the upper thoracic spine. The adverse event profile did not differ significantly, but longer surgical time and blood loss were associated with construct extending across the CTJ.

Open limb fractures are typically due to a high energy trauma. Several recent studied have showed treatment's superiority when a multidisciplinary approach is applied. World Health Organization reports that isolate limb traumas have an incidence rate of 11.5/100.000, causing high costs in terms of hospitalization and patient disability.

A lack of experience in soft tissue management in orthopaedics and traumatology seems to be the determining factor in the clinical worsening of complex cases. The therapeutic possibilities offered by microsurgery currently permit simultaneous reconstruction of multiple tissues including vessels and nerves, reducing the rate of amputations, recovery time and preventing postoperative complications.

Several scoring systems to assess complex limb traumas exist, among them: NISSSA, MESS, AO and Gustilo Anderson. In 2010, a further scoring system was introduced to focus open fractures of all locations: OTA-OFC. Rather than using a single composite score, the OTA-OFC comprises five components grades (skin, arterial, muscle, bone loss and contamination), each rated from mild to severe. The International Consensus Meeting of 2018 on musculoskeletal infections in orthopaedic surgery identified the OTA-OFC score as an efficient catalogue system with interobserver agreement that is comparable or superior to the Gustilo-Anderson classification. OTA-OFC predicts outcomes such as the need for adjuvant treatments or the likelihood of early amputation. An orthoplastic approach reconstruction must pay adequate attention to bone and soft tissue infections management. Concerning bone management: there is little to no difference in terms of infection rates for Gustilo-Anderson types I–II treated by reamed intramedullary nail, circular external fixator, or unreamed intramedullary nail. In Gustilo-Anderson IIIA-B fractures, circular external fixation appears to provide the lowest infection rates when compared to all other fixation methods.

Different technique can be used for the reconstruction of bone and soft tissue defects based on each clinical scenario. Open fracture management with fasciocutaneous or muscle flaps shows comparable outcomes in terms of bone healing, soft tissue coverage, acute infection and chronic osteomyelitis prevention. The type of flap should be tailored based on the type of the defect, bone or soft tissue, location, extension and depth of the defect, size of the osseous gap, fracture type, and orthopaedic implantation. Local flaps should be considered in low energy trauma, when skin and soft tissue is not traumatized. In high energy fractures with bone exposure, muscle flaps may offer a more reliable reconstruction with fewer flap failures and lower reoperation rates. On exposed fractures several studies report precise timing for a proper reconstruction. Hence, timing of soft tissue coverage is a critical for length of in-hospital stay and most of the early postoperative complications and outcomes. Early coverage has been associated with higher union rates and lower complications and infection rates compared to those reconstructed after 5-7 days. Furthermore, early reconstruction improves flap survival and reduces surgical complexity, as microsurgical free flap procedures become more challenging with a delay due to an increased pro-thrombotic environment, tissue edema and the increasingly friable vessels.

Only those patients presenting to facilities with an actual dedicated orthoplastic trauma service are likely to receive definitive treatment of a severe open fracture with tissue loss within the established parameters of good practice. We conclude that the surgeon's experience appears to be the decisive element in the orthoplastic approach, although reconstructive algorithms may assist in decisional and planification of surgery.

Aim

Aim of this monocentric, prospective study was to evaluate the safety, efficacy, clinical and radiographical results at 24-month follow-up (N = 6 patients) undergoing hip revision surgery with severe acetabular bone defects (Paprosky 2C-3A-3B) using a combination of a novel phase-pure betatricalciumphosphate - collagen 3D matrix with allograft bone chips.

Abstract

Aim

This study investigated if co-administration of rifampicin with moxifloxacin led to a decrease in moxifloxacin concentrations in relevant tissues in a porcine model of implant-associated osteomyelitis caused S. aureus. Pharmacokinetics were measured using microdialysis and treatment effect was measured by quantifying bacterial load from implant and periprosthetic bone following a 1-stage revision and antibiotics.

With the coronavirus disease 2019 (COVID-19) pandemic, remote working has been ubiquitously implemented to reduce disease transmission via minimization of in-person interactions. Low back pain (LBP) is the first cause of disability worldwide and is frequently reported by workers with sedentary occupations. This cross-sectional study aimed to assess the role of remote working in a population of adults affected by LBP through an online questionnaire.

We enrolled 136 teleworkers affected by LBP. A total of 101 responses were received and 93 suitable questionnaires were included in the final analysis. Demographic data, remote working features and tasks, and LBP burden were analysed. The psychological burden of remote working was evaluated with the World Health Organization Five Well-Being Index (WHO-5) and the Patient Health Questionnaire-2 (PHQ-2). LBP severity was evaluated using a visual analog scale (VAS). LBP-related disability was assessed using the Oswestry Disability Index (ODI). The effect of LBP on working capacity was examined with the Occupational Role Questionnaire (ORQ). Independent risk factors related to LBP worsening were identified using a multivariate logistic regression model.

LBP severity was significantly higher compared to previous in-person working (p<0.0001) as well as average weekly work hours (p<0.001). Furthermore, the risk of LBP deterioration was associated with being divorced (OR: 4.28, 95% CI: 1.27-14.47; p=0.019) or living with others (OR: 0.24, 95% CI: 0.07-0.81; p=0.021), higher ill-being (OR: 0.91, 95% CI: 0.83-0.99; p=0.035) and depression scores (OR: 1.38, 95% CI: 1.00-1.91; p=0.048), as well as having reported unchanged (OR: 0.22, 95% CI: 0.08-0.65; p=0.006) or decreased job satisfaction (OR: 0.16, 95% CI: 0.05-0.54; p=0.003) and increased stress levels (OR: 3.00, 95% CI: 1.04-8.65; p=0.042).

These findings highlight key factors to consider for improving remote workers’ physical and mental wellbeing and decrease their LBP burden.

En bloc resection for primary bone tumours and isolated metastasis are complex surgeries associated with a high rate of adverse events (AEs). The primary objective of this study was to explore the relationship between frailty/sarcopenia and major perioperative AEs following en bloc resection for primary bone tumours or isolated metastases of the spine. Secondary objectives were to report the prevalence and distribution of frailty and sarcopenia, and determine the relationship between these factors and length of stay (LOS), unplanned reoperation, and 1-year postoperative mortality in this population.

This is a retrospective study of prospectively collected data from a single quaternary care referral center consisting of patients undergoing an elective en bloc resection for a primary bone tumour or an isolated spinal metastasis between January 1st, 2009 and February 28th, 2020. Frailty was calculated with the modified frailty index (mFI) and spine tumour frailty index (STFI). Sarcopenia, determined by the total psoas area (TPA) vertebral body (VB) ratio (TPA/VB), was measured at L3 and L4. Regression analysis produced ORs, IRRs, and HRs that quantified the association between frailty/sarcopenia and major perioperative AEs, LOS, unplanned reoperation and 1-year postoperative mortality.

One hundred twelve patients met the inclusion criteria. Using the mFI, five patients (5%) were frail (mFI ³ 0.21), while the STFI identified 21 patients (19%) as frail (STFI ³ 2). The mean CT ratios were 1.45 (SD 0.05) and 1.81 (SD 0.06) at L3 and L4 respectively. Unadjusted analysis demonstrated that sarcopenia and frailty were not significant predictors of major perioperative AEs, LOS or unplanned reoperation. Sarcopenia defined by the CT L3 TPA/VB and CT L4 TPA/VB ratios significantly predicted 1-year mortality (HR of 0.32 per one unit increase, 95% CI 0.11-0.93, p=0.04 vs. HR of 0.28 per one unit increase, 95% CI 0.11-0.69, p=0.01) following unadjusted analysis. Frailty defined by an STFI score ≥ 2 predicted 1-year postoperative mortality (OR of 2.10, 95% CI 1.02-4.30, p=0.04).

The mFI was not predictive of any clinical outcome in patients undergoing en bloc resection for primary bone tumours or isolated metastases of the spine. Sarcopenia defined by the CT L3 TPA/VB and L4 TPA/VB and frailty assessed with the STFI predicted 1-year postoperative mortality on univariate analysis but not major perioperative AEs, LOS or reoperation. Further investigation with a larger cohort is needed to identify the optimal measure for assessing frailty and sarcopenia in this spine population.

Abstract

Operative management of clavicle fractures is increasingly common. In the context of explaining the risks and benefits of surgery, understanding the impact of incisional numbness as it relates to the patient experience is key to shared decision making. This study aims to determine the prevalence, extent, and recovery of sensory changes associated with supraclavicular nerve injury after open reduction and plate internal fixation of middle or lateral clavicle shaft fractures.

Eighty-six patients were identified retrospectively and completed a patient experience survey assessing sensory symptoms, perceived post-operative function, and satisfaction. Correlations between demographic factors and outcomes, as well as subgroup analyses were completed to identify factors impacting patient satisfaction.

Ninety percent of patients experienced sensory changes post-operatively. Numbness was the most common symptom (64%) and complete resolution occurred in 32% of patients over an average of 19 months. Patients who experienced burning were less satisfied overall with the outcome of their surgery whereas those who were informed of the risk of sensory changes pre-operatively were more satisfied overall.

Post-operative sensory disturbance is common. While most patients improve, some symptoms persist in the majority of patients without significant negative effects on satisfaction. Patients should always be advised of the risk of persistent sensory alterations around the surgical site to increase the likelihood of their satisfaction post-operatively.

Aim

Patients with late acute periprosthetic joint infections (PJI) and treated with surgical debridement have a high failure rate. Previous studies have shown that rheumatoid arthritis (RA) is an independent risk factor for treatment failure. We conducted a case-control study to identify predictors for failure in late acute PJI treatment in RA patients. We hypothesize that patients with RA have a higher failure rate compared to controls due to the use of immunosuppressive drugs.

Paediatric musculoskeletal (MSK) disorders often produce severe limb deformities, that may require surgical correction. This may be challenging, especially in case of multiplanar, multifocal and/or multilevel deformities. The increasing implementation of novel technologies, such as virtual surgical planning (VSP), computer aided surgical simulation (CASS) and 3D-printing is rapidly gaining traction for a range of surgical applications in paediatric orthopaedics, allowing for extreme personalization and accuracy of the correction, by also reducing operative times and complications. However, prompt availability and accessible costs of this technology remain a concern. Here, we report our experience using an in-hospital low-cost desk workstation for VSP and rapid prototyping in the field of paediatric orthopaedic surgery.

From April 2018 to September 2022 20 children presenting with congenital or post-traumatic deformities of the limbs requiring corrective osteotomies were included in the study. A conversion procedure was applied to transform the CT scan into a 3D model. The surgery was planned using the 3D generated model. The simulation consisted of a virtual process of correction of the alignment, rotation, lengthening of the bones and choosing the level, shape and direction of the osteotomies. We also simulated and calculated the size and position of hardware and customized massive allografts that were shaped in clean room at the hospital bone bank. Sterilizable 3D models and PSI were printed in high-temperature poly-lactic acid (HTPLA), using a low-cost 3D-printer.

Twenty-three operations in twenty patients were performed by using VSP and CASS. The sites of correction were: leg (9 cases) hip (5 cases) elbow/forearm (5 cases) foot (5 cases) The 3D printed sterilizable models were used in 21 cases while HTPLA-PSI were used in five cases. customized massive bone allografts were implanted in 4 cases. No complications related to the use of 3D printed models or cutting guides within the surgical field were observed. Post-operative good or excellent radiographic correction was achieved in 21 cases.

In conclusion, the application of VSP, CASS and 3D-printing technology can improve the surgical correction of complex limb deformities in children, helping the surgeon to identify the correct landmarks for the osteotomy, to achieve the desired degree of correction, accurately modelling and positioning hardware and bone grafts when required. The implementation of in-hospital low-cost desk workstations for VSP, CASS and 3D-Printing is an effective and cost-advantageous solution for facilitating the use of these technologies in daily clinical and surgical practice.

Abstract

Abstract

Lumbar fusion surgery is an established procedure for the treatment of several spinal pathologies. Despite numerous techniques and existing devices, common surgical trends in lumbar fusion surgery are scarcely investigated. The purpose of this Canada-based study was to provide a descriptive portrait of current surgeons’ practice and implant preferences in lumbar fusion surgery while comparing findings to similar investigations performed in the United Kingdom.

Canadian Spine Society (CSS) members were sampled using an online questionnaire which was based on previous investigations performed in the United Kingdom. Fifteen questions addressed the various aspects of surgeons’ practice: fusion techniques, implant preferences, and bone grafting procedures. Responses were analyzed by means of descriptive statistics.

Of 139 eligible CSS members, 41 spinal surgeons completed the survey (29.5%). The most common fusion approach was via transforaminal lumber interbody fusion (TLIF) with 87.8% performing at least one procedure in the previous year. In keeping with this, 24 surgeons (58.5%) had performed 11 to 50 cases in that time frame. Eighty-six percent had performed no lumbar artificial disc replacements over their last year of practice. There was clear consistency on the relevance of a patient specific management (73.2%) on the preferred fusion approach. The most preferred method was pedicle screw fixation (78%). The use of stand-alone cages was not supported by any respondents. With regards to the cage material, titanium cages were the most used (41.5%). Published clinical outcome data was the most important variable in dictating implant choice (87.8%). Cage thickness was considered the most important aspect of cage geometry and hyperlordotic cages were preferred at the lower lumbar levels. Autograft bone graft was most commonly preferred (61.0%). Amongst the synthetic options, DBX/DBM graft (64.1%) in injectable paste form (47.5%) was preferred.

In conclusion, findings from this study are in partial agreement with previous work from the United Kingdom, but highlight the variance of practice within Canada and the need for large-scale clinical studies aimed to set specific guidelines for certain pathologies or patient categories.

Adverse events (AEs) are still a major problem in spinal surgery, despite advances in surgical techniques, innovative technologies available and the introduction of checklist and predictive score systems aimed at reducing surgical complications.

We previously analysed the results of the introduction of the WHO Safety Surgical Checklist (SSC) in our Institution, comparing the incidence of complications between two periods: from January to December 2010 (without checklist) and from January 2011 and December 2012 (with checklist), in order to assess the checklist effectiveness.

The sample size was 917 patients with an average of 30 months of follow-up. Complications were observed in 107 patients (11.6%) among 917 spinal surgery procedures performed, with 159 (17.3%) complications in total. The overall incidence of complications for trauma, infectious pathology, oncology, and degenerative disease was 22.2%, 19.2%, 18.4%, and 15.3%, respectively. We observed a reduction of the overall incidence of complications following the introduction of the WHO Surgical Checklist: in 2010 without checklist, the incidence of complications was 24.2%, while in 2011 and 2012, following the checklist introduction, the incidence of complications was 16.7% and 11.7%, respectively (mean 14.2%) (p<0.0005).

Thus, the SSC appeared to be an effective tool to reduce complications in spinal surgery and we proposed to extend the use of checklist system also to the pre-operative and post-operative phases in order to further reduce the incidence of complications.

We also believe that a correct capture and classification of complications is fundamental to generate a clinical decision support system aimed at improving patients’ safety in spinal surgery.

In the period between January 2017 and January 2018 we prospectively recorded the adverse events and complications of patients undergoing spinal surgery in our department, without using any collection system. Then we retrospectively recorded the intraoperative and postoperative adverse events of surgically treated patients during the same one-year period, using the SAVES v2 system introduced by Rampersaud and collaborators (Rampersaud YR et al. J Neurosurg Spine 2016 Aug; 25 (2): 256-63) to classify them.

In the one-year period from January 2017 to January 2018 a total of 336 patients underwent spinal surgery: 223 for degenerative conditions and 113 for spinal tumors. Comorbidities were collected (Charlson Comorbidity Index [CCI]).

Overall, a higher number of adverse events (AEs) was recorded using SAVES compared to the prospective recording without the use of any capture system and the increased number was statistically significant for early postoperative AEs (138/336 vs 44/336, p<0.001).

210 adverse events were retrospectively recorded using the SAVES system (30 intraoperative adverse events, 138 early postoperative and 42 late postoperative adverse events). 99 patients (29.5%) on the cohort had at least one complication.

Furthermore, the correlation between some risk factors and the onset of complications or the prolonged length of stay was statistically analyzed. The risk factors taken into account were: age, presence of comorbidities (CCI), ASA score, previous surgery at the same level, type of intervention, location of the disease, duration of the surgery.

In particular, the duration of the surgery (more than 3 hours) and the presence of previous surgeries resulted to be risk factors for complications in multivariate analyses

Pain and disability following wrist trauma are highly prevalent, however the mechanisms underlying painare highly unknown. Recent studies in the knee have demonstrated that altered joint contact may induce changes to the subchondral bone density and associated pain following trauma, due to the vascularity of the subchondral bone. In order to examine these changes, a depth-specific imaging technique using quantitative computed tomography (QCT) has been used. We've demonstrated the utility of QCT in measuring vBMD according to static jointcontact and found differences invBMD between healthy and previously injured wrists. However, analyzing a static joint in a neutral position is not necessarily indicative of higher or lower vBMD. Therefore, the purposeof this study is to explore the relationship between subchondral vBMDand kinematic joint contact using the same imaging technique.

To demonstrate the relationship between kinematic joint contact and subchondral vBMDusing QCT, we analyzed the wrists of n = 10 participants (n = 5 healthy and n = 5 with previous wrist trauma). Participantsunderwent 4DCT scans while performing flexion to extension to estimate radiocarpal (specifically the radiolunate (RL) and radioscaphoid (RS)) joint contact area (JCa) between the articulating surfaces. The participantsalso underwent a static CT scan accompanied by a calibration phantom with known material densities that was used to estimate subchondral vBMDof the distal radius. Joint contact is measured by calculatinginter-bone distances (mm2) using a previously validated algorithm. Subchondral vBMD is presented using mean vBMD (mg/K2HPO4) at three normalized depths from the subchondral surface (0 to 2.5, 2.5 to 5 and 5 to 7.5 mm) of the distal radius.

The participants in the healthy cohort demonstrated a larger JCa in the RS joint during both extension and flexion, while the trauma cohort demonstrated a larger JCa in the RL during extension and flexion. With regards to vBMD, the healthy cohort demonstrated a higher vBMD for all three normalized depths from the subchondral surface when compared to the trauma cohort.

Results from our preliminary analysis demonstrate that in the RL joint specifically, a larger JCa throughout flexion and extension was associated with an overall lower vBMD across all three normalized layers. Potential reasoning behind this association could be that following wrist trauma, altered joint contact mechanics due to pathological changes (for example, musculoskeletal trauma), has led to overloading in the RL region. The overloading on this specific region may have led to a decrease in the underlying vBMD when compared to a healthy wrist. However, we are unable to conclude if this is a momentary decrease in vBMD that could be associated with the acute healing phase following trauma given that our analysis is cross-sectional. Therefore, future work should aim to analyze kinematic JCa and vBMD longitudinally to better understand how changes in kinematic JCa over time, and how the healing process following wrist trauma, impacts the underlying subchondral bone in the acute and longitudinal phases of recovery.

Revision surgeries for orthopaedic infections are done in two stages – one surgery to implant an antibiotic spacer to clear the infection and another to install a permanent implant. A permanent porous implant, that can be loaded with antibiotics and allow for single-stage revision surgery, will benefit patients and save healthcare resources. Gyroid structures can be constructed with high porosity, without stress concentrations that can develop in other period porous structures [1] [2]. The purpose of this research is to compare the resulting bone and prosthesis stress distributions when porous versus solid stems are implanted into three proximal humeri with varying bone densities, using finite element models (FEM).

Porous humeral stems were constructed in a gyroid structure at porosities of 60%, 70%, and 80% using computer-aided design (CAD) software. These CAD models were analyzed using FEM (Abaqus) to look at the stress distributions within the proximal humerus and the stem components with loads and boundary conditions representing the arm actively maintained at 120˚ of flexion. The stem was assumed to be made of titanium (Ti6Al4V). Three different bone densities were investigated, representing a healthy, an osteopenic, and an osteoporotic humerus, with an average bone shape created using a statistical shape and density model (SSDM) based on 75 cadaveric shoulders (57 males and 18 females, 73 12 years) [3]. The Young's moduli (E) of the cortical and trabecular bones were defined on an element-by-element basis, with a minimum allowable E of 15 MPa. The Von Mises stress distributions in the bone and the stems were compared between different stem scenarios for each bone density model.

A preliminary analysis shows an increase in stress values at the proximal-lateral region of the humerus when using the porous stems compared to the solid stem, which becomes more prominent as bone density decreases. With the exception of a few mesh dependent singularities, all three porous stems show stress distributions below the fatigue strength of Ti-6Al-4V (410 MPa) for this loading scenario when employed in the osteopenic and osteoporotic humeri [4]. The 80% porosity stem had a single strut exceeding the fatigue strength when employed in the healthy bone.

The results of this study indicate that the more compliant nature of the porous stem geometries may allow for better load transmission through the proximal humeral bone, better matching the stress distributions of the intact bone and possibly mitigating stress-shielding effects. Importantly, this study also indicates that these porous stems have adequate strength for long-term use, as none were predicted to have catastrophic failure under the physiologically-relevant loads. Although these results are limited to a single boney geometry, it is based on the average shape of 75 shoulders and different bone densities are considered. Future work could leverage the shape model for probabilistic models that could explore the effect of stem porosity across a broader population. The development of these models are instrumental in determining if these structures are a viable solution to combatting orthopaedic implant infections.

Aim

Studies have shown that retention of antibiotic cement spacer in selected elderly patients with low functional demand represents a viable option for periprosthetic joint infections (PJI) treatment^1,2.

The aim of this study is to compare the efficacy in infection treating among modular taylored preformed and hand-made antibiotic spacers. Our hypothesis is that modular tailored preformed spacer provides a better rate of infection resolution, better radiological and functional outcomes compared to hand-made spacers.

Arthroscopic hip procedures have increased dramatically over the last decade as equipment and techniques have improved. Patients who require hip arthroscopy for femoroacetabular impingement on occasion require surgery on the contralateral hip. Previous studies have found that younger age of presentation and lower Charlson comorbidity index have higher risk for requiring surgery on the contralateral hip but have not found correlation to anatomic variables. The purpose of this study is to evaluate the factors that predispose a patient to requiring subsequent hip arthroscopy on the contralateral hip.

This is an IRB-approved, single surgeon retrospective cohort study from an academic, tertiary referral centre. A chart review was conducted on 310 primary hip arthroscopy procedures from 2009-2020. We identified 62 cases that went on to have a hip arthroscopy on the contralateral side. The bilateral hip arthroscopy cohort was compared to unilateral cohort for sex, age, BMI, pre-op alpha angle and centre edge angle measured on AP pelvis XRay, femoral torsion, traction time, skin to skin time, Tonnis grade, intra-op labral or chondral defect. A p-value <0.05 was deemed significant.

Of the 62 patients that required contralateral hip arthroscopy, the average age was 32.7 compared with 37.8 in the unilateral cohort (p = 0.01) and BMI was lower in the bilateral cohort (26.2) compared to the unilateral cohort (27.6) (p=0.04). The average alpha angle was 76.3⁰ in the bilateral compared to 66⁰ in the unilateral cohort (p = 0.01). Skin to skin time was longer in cases in which a contralateral surgery was performed (106.3 mins vs 86.4 mins) (p=0.01). Interestingly, 50 male patients required contralateral hip arthroscopy compared to 12 female patients (p=0.01). No other variables were statistically significant.

In conclusion, this study does re-enforce existing literature by stating that younger patients are more likely to require contralateral hip arthroscopy. This may be due to the fact that these patients require increased range of motion from the hip joint to perform activities such as sports where as older patients may not need the same amount of range of motion to perform their activities. Significantly higher alpha angles were noted in patients requiring contralateral hip arthroscopy, which has not been shown in previous literature. This helps to explain that larger CAM deformities will likely require contralateral hip arthroscopy because these patients likely impinge more during simple activities of daily living. Contralateral hip arthroscopy is also more common in male patients who typically have a larger CAM deformity. In summary, this study will help to risk stratify patients who will likely require contralateral hip arthroscopy and should be a discussion point during pre-operative counseling. That offering early subsequent or simultaneous hip arthroscopy in young male patients with large CAMs should be offered when symptoms are mild.

Abstract

A concern of metal on metal hip resurfacing arthroplasty is long term exposure to Cobalt (Co) and Chromium (CR) wear debris from the bearing. This study compares whole blood metal ion levels from patients drawn at one-year following Birmingham Hip Resurfacing (BHR) to levels taken at a minimum 10-year follow-up.

A retrospective chart review was conducted to identify all patients who underwent a BHR for osteoarthritis with a minimum 10-year follow-up. Whole blood metal ion levels were drawn at final follow-up in June 2019. These results were compared to values from patients with one-year metal ion levels.

Of the 211 patients who received a BHR, 71 patients (54 males and 17 females) had long term metal ion levels assessed (mean follow-up 12.7 +/− 1.4 years). The mean Co and Cr levels for patients with unilateral BHRs (43 males and 13 females) were 3.12 ± 6.31 ug/L and 2.62 ± 2.69 ug/L, respectively, and 2.78 ± 1.02 ug/L and 1.83 ± 0.65 ug/L for patients with bilateral BHRs (11 males and 4 females). Thirty-five patients (27 male and 8 female) had metal-ion levels tested at one-year postoperatively. The mean changes in Co and Cr levels were 2.29 ug/l (p = 0.0919) and 0.57 (p = 0.1612), respectively, at one year compared to long-term. These changes were not statistically significant.

This study reveals that whole blood metal ion levels do not change significantly when comparing one-year and ten-year Co and Cr levels. These ion levels appear to reach a steady state at one year.

Our results also suggest that regular metal-ion testing as per current Medicines and Healthcare products Regulatory Agency (MHRA) guidelines may be impractical for asymptomatic patients. Metal-ion levels, in and of themselves, may in fact possess little utility in determining the risk of failure and should be paired with radiographic and clinical findings to determine the need for revision.

Aim

To evaluate the efficiency of pulse lavage combined with electrical fields to remove biofilm from a metallic surface.

Aim

Synovial fluid D-lactate may be useful for diagnosing septic arthritis (SA) as this biomarker is almost exclusively produced by bacteria. We evaluated the performance of synovial fluid D-lactate and determined its optimal cut-off value for diagnosing SA.

Background

Surgical site infection following spine surgery is associated with increased morbidity, mortality and increased cost for the health care system. The reported pooled incidence is 3%. Perioperative antibiotic prophylaxis is a key factor in lowering the risk of acquiring an infection. Previous studies have assessed perioperative cefuroxime concentrations in the anterior column of the cervical spine with an anterior surgical approach. However, the majority of surgeries are performed in the posterior column and often involve the lumbar spine. Accordingly, the objective was to compare the perioperative tissue concentrations of cefuroxime in the anterior and posterior column of the same lumbar vertebra using microdialysis in an experimental porcine model.

Immigrated Canadians make up approximately 20% of the total population in Canada, and 30% of the population in Ontario. Despite universal health coverage and an equal prevalence of severe arthritis in immigrants relative to non-immigrants, the former may be underrepresented amongst arthroplasty recipients secondary to challenges navigating the healthcare system. The primary aim of this study was to determine if utilization of arthroplasty differs between immigrant populations and persons born in Canada. The secondary aim was to determine differences in outcomes following total hip and knee arthroplasty (THA and TKA, respectively).

This is a retrospective population-based cohort study using health administrative databases. All patients aged ≥18 in Ontario who underwent their first primary elective THA or TKA between 2002 and 2016 were identified. Immigration status for each patient was identified via linkage to the ‘Immigration, Refugee and Citizenship Canada’ database. Outcomes included all-cause and septic revision surgery within 12-months, dislocation (for THA) and total post-operative case cost and were compared between groups. Cochrane-Armitage Test for Trend was utilized to determine if the uptake of arthroplasty by immigrants changed over time.

There was a total of 186,528 TKA recipients and 116,472 THA recipients identified over the study period. Of these, 10,193 (5.5%) and 3,165 (2.7%) were immigrants, respectively. The largest proportion of immigrants were from the Asia and Pacific region for those undergoing TKA (54.0%) and Europe for THA recipients (53.4%). There was no difference in the rate of all-cause revision or septic revision at 12 months between groups undergoing TKA (p=0.864, p=0.585) or THA (p=0.527, p=0.397), respectively. There was also no difference in the rate of dislocations between immigrants and people born in Canada (p=0.765, respectively).

Despite having similar complication rates and costs, immigrants represent a significantly smaller proportion of joint replacement recipients than they represent in the general population in Ontario. These results suggest significant underutilization of surgical management for arthritis among Canada's immigrant populations. Initiatives to improve access to total joint arthroplasty are warranted.

Over 500 supracondylar humerus fractures (SCHF) are treated at our institution each year. Our standard post-operative pathway includes a 3-week visit for splint removal, wire removal, and radiographs. Subsequent follow-up occurs at 12 weeks for a clinical examination. In an effort to minimize unnecessary follow-up visits, we investigated whether photographs and/or patient-reported outcome measure (PROM) scores could identify patients who do not need routine 3-month in-person follow-up.

At the 3-month visit, 248 SCHF patients (mean 6.2 yrs; 0.75-11yrs) had bilateral elbow motion (ROM) and carrying angles measured; and photographs documenting frontal and sagittal alignment of both injured and uninjured upper extremities, in both maximum elbow flexion and extension. Two independent assessors made the same measurements off the clinical photographs to compare these with the clinical measurements. Two PROMs: Self-Assessment Questionnaire (SAQ: 0 best to 14 worst) and QuickDASH (0 best to 100 worst) were completed at the 3-month visit.

Inter-rater reliability of the photograph measurements was excellent (Kappa: 0.88-0.93), but weakly concordant with clinical measurements (carrying angle Kappa=0.51;max flexion Kappa=0.68;max extension Kappa=0.64). SAQ moderately correlated with QuickDASH (Kappa=0.59) and performed better at identifying patients with abnormalities. SAQ score ≥ 4 identified patients meeting 3-month follow-up criteria, with sensitivity: 36.1%; specificity: 96.8% and negative-predictive-value (NPV): 87%.

We did not find that photographs were reliable. Although SAQ-score has high NPV, a more sensitive fracture-specific PROM is needed to identify patients who do not need a 3-month follow-up visit.

Aim

A novel anti-infective biopolymer implant coating was developed to prevent bacterial biofilm formation and allow on-demand burst release of anti-infective silver (Ag) into the surrounding of the implant at any time after surgery via focused high-energy extracorporeal shock waves (fhESW).

To date, the literature has not yet revealed superiority of Minimally Invasive (MI) approaches over conventional techniques. We performed a systematic review to determine whether minimally invasive approaches are superior to conventional approaches in total hip arthroplasty for (1) clinical and (2) functional outcomes. We performed a meta-analysis of level 1 evidence to determine whether (3) minimally invasive approaches are superior to conventional approaches for clinical outcomes.

All studies comparing MI approaches to conventional approaches were eligible for analysis. The PRISMA guidelines were adhered to throughout this study. Registries were searched using the following MeSH terms: ‘minimally invasive’, ‘muscle-sparing’, ‘THA’, ‘THR’, ‘hip arthroplasty’ and ‘hip replacement’. Locations searched included PubMed, the Cochrane Library, ClinicalTrials.gov, the EU clinical trials register and the International Clinical Trials Registry Platform (World Health Organisation).

Twenty studies were identified. There were 1,282 MI THAs and 1,351 conventional THAs performed.

Intermuscular MI approaches are equivalent to conventional THA approaches when considering all-cause revision, aseptic revision, infection, dislocation, fracture rates and functional outcomes. Meta-analysis of level 1 evidence supports this claim.

Abstract

Abstract

Abstract

Abstract

There is a need for non-radiographic, objective outcome measures for children with Adolescent Idiopathic Scoliosis (AIS). Standing balance and stability is altered in children with AIS. The Margin of Stability (MoS) has been used to compare gait stability in clinical populations. Our objective was to compare the MoS in anterior-posterior (MoS_AP) and mediolateral (MoS_ML) directions in girls with AIS to Controls.

Girls with AIS and healthy girls walked at three speeds on an instrumented treadmill wearing retroreflective markers, surrounded by motion capture cameras. The MoS_AP/ML was calculated at left and right heel strike. Data was processed in Visual 3D. A two-way ANOVA was used to compare MoS_AP/ML between group, speed and the interaction between group and speed. Pearson's correlation coefficient was used to compare the MoS to Cobb angle. Statistical significance was accepted when p > 0.05.

A priori power analysis suggested 12 participants per group. Three Cases and four Controls were recruited. Girls with AIS all had right-sided main thoracic curves (Lenke type 1a, 61.3° ± 10.0°). MoS_AP was significantly bigger for Cases compared to Controls on the left (p=0.038) and right foot (p=0.041). There was no significant difference between Cases and Controls for MoS_ML, but there was a visual trend for a smaller MoS_ML in Cases. There was no significant difference for speed or the interaction between group and speed for MoS_AP or MoS_ML. In Cases, MoS_AP increased with increasing Cobb angle on the left (r²=0.687, p=0.054) and right (r²=0.634, p=0.067) and MoS_ML decreased with increasing Cobb angle on the left (r²=-0.912, p=0.002). Further subjects are being recruited.

Girls with Lenke type 1a AIS are more stable in the AP direction and less stable in the ML direction than Controls during treadmill walking. AP stability increases and ML stability decreases with increasing Cobb angle. This research suggests that the MoS could be used as an outcome measure for children with AIS. Continued work is required to increase the power of this study. Further work could consider these changes during walking overground, measuring an MoS or MoS-like measure using a wearable device, and in different curve types.

Cartilage lesions vary in the spectrum from benign enchondromas to highly malignant dedifferentiated chondrosarcomas. From the treatment perspective, enchondromas are observed, Grade 1 chondrosarcomas are curetted like aggressive benign tumors, and rest are resected like other sarcomas. Although biopsy for tissue diagnosis is the gold standard for diagnosis and grade determination in chondrosarcoma, tumor heterogeneity limits the grading in patients following a biopsy. In the absence of definite pre-treatment grading, a surgeon is therefore often in a dilemma when deciding the best treatment option. Radiology has identified aggressive features and aggressiveness scores have been used to try and grade these tumors based on the imaging characteristics but there have been very few published reports with a uniform group and large number of cases to derive a consistent scoring and correlation.

The authors asked these study questions :(1) Does Radiology Aggressiveness and its Score correlate with the grade of chondrosarcoma? (2) Can a cut off Radiology Agressiveness Score value be used to guide the clinician and add value to needle biopsy information in offering histological grade dependent management?

A retrospective analysis of patients with long bone extremity intraosseous primary chondrosarcomas were correlated with the final histology grade for the operated patients and Radiological parameters with 9 parameters identified a priori and from published literature (radiology aggressiveness scores - RAS) were evaluated and tabulated. 137 patients were identified and 2 patients were eliminated for prior surgical intervention. All patients had tissue diagnosis available and pre-treatment local radiology investigations (radiographs and/or CT scans and MRI scans) to define the RAS parameters.

Spearman correlation has indicated that there was a significant positive association between RAS and final histology grading of long bone primary intraosseous chondrosarcomas. We expect higher RAS values will provide grading information in patients with inconclusive pre-surgery biopsy to tumor grades and aid in correct grade dependant surgical management of the lesion. Prediction of dedifferentiated chondrosarcoma from higher RAS will be attempted and a correlation to obtain a RAS cut off, although this may be challenging to achieve due to the overlap of features across the intermediate grade, high grade and dedifferentiated grades.

Radiology Aggressiveness correlates with the histologic grade in long bone extremity primary chondrosarcomas and the correlation of radiology and biopsy can aid in treatment planning by guiding us towards a low-grade neoplasm which may be dealt with intralesional extended curettage or high-grade lesion which need to be resected. Standalone RAS may not solve the grading dilemma of primary long bone intraosseous chondrosarcomas as the need for tissue diagnosis for confirming atypical cartilaginous neoplasm cannot be eliminated, however in the event of a needle biopsy grade or inconclusive open biopsy it may guide us towards a correlational diagnosis along with radiology and pathology for grade based management of the chondrosarcoma.

Abstract

Abstract

Abstract

Children undergoing posterior spinal fusion (PSF) for neuromuscular and syndromic scoliosis were admitted to the paediatric intensive care (PIC) until about 6 years ago, at which time we created a new unit, a hospital floor-based spinal high-dependency unit-plus (SHDU-plus), in response to frequent bed-shortage cancellations. This study compares postoperative management on PIC with HDU-plus for these non-hospital floor suitable children with syndromic and neuromuscular scoliosis undergoing PSF.

Retrospective review of 100 consecutive children with syndromic and neuromuscular scoliosis undergoing PSF between June 2016 and January 2022. Inclusion criteria were: 1) diagnosis of syndromic or neuromuscular scoliosis, 2) underwent PSF, 3) not suitable for immediate postoperative hospital floor-based care. Exclusion criteria were children with significant cardio-respiratory co-morbidity requiring PIC postoperatively.

55 patients were managed postoperatively on PIC and 45 on SHDU-plus. No significant difference between groups was found with respect to age, weight, ASA grade, preoperative Cobb angles, operative duration, number of levels fused and estimated blood loss. 4 patients in the PIC group and 1 in the SHDU-plus group were readmitted back to PIC or HDU following step-down to the hospital floor. Average length of stay was 2 days on PIC and 1 day on SHDU-plus. Average total length of hospital stay was 16.5 days in the PIC group and 10.5 days in the HDU-plus group. 19 (35%) patients developed complications in the PIC group, compared to 18 (40%) in SHDU-plus. Mean specialist unit charge per day was less on SHDU-plus compared with PIC. There were no bed-shortage cancellations in the SHDU-plus group, compared to 11 in the PIC group.

For children with neuromuscular or syndromic scoliosis undergoing PSF and deemed not suitable for post-operative care on the hospital floor, creation of a SHDU-plus was associated with fewer readmissions back to PIC or HDU, shorter hospital stays, an equivalent complication rate, significant cost-saving and fewer cancellations. Level of Evidence: Therapeutic Level III.

Introduction

Transfemoral osseointegration (TFOI) for amputees has substantial literature proving superior quality of life and mobility versus a socketed prosthesis. Some amputees have hip arthritis that would be relieved by a total hip replacement (THR). No other group has reported performing a THR in association with TFOI (THR+TFOI). We report the outcomes of eight patients who had THR+TFOI, followed for an average 5.2 years.

The early revision rate in elective Total Hip Arthroplasty (THA) three years after surgery in elderly patients over 80 years is significantly lower for cemented stems in the German Arthroplasty Register (EPRD): cemented 3,1% (3.0 – 3.2) vs. uncemented 4.2% (4.1 – 4.3; p < 0.001). However, the mortality rate in elderly patients is elevated for cemented fixation. This study presents a detailed analysis of the influence of stem type and fixation on revision and mortality rate in this patient cohort.

Elective primary THA cases for primary Coxarthrosis using uncemented cups from the EPRD data base were analysed (n₀= 37,183). Four stem type groups were compared: cementless, cementless with collar, cementless short, and cemented. Stems with at least 300 cases at risk three years after surgery were analysed individually. The reference stem was determined as the stem with the lowest revision rate and at least 1000 cases under surveillance 3 years after surgery (n₃ = 28,637).

The revision rate for cemented stems (2.5% [2.2–1.81] was lower than for uncemented (4.5% [4.2–4.9]; p<0.001) and uncemented short stems (4.2% [3.1–5.7]; p=0.002). The revision rate of uncemented collared stems (2.3% [1.5–3.6]) was similar to cemented stems (p=0.89) and lower than for uncemented stems (p=0.02). One year mortality showed no sig. differences between the groups (p>0.17): cemented 3.2% [2.9–3.6], uncemented 3.4% [3.1–3.7], uncemented short 3.5% [2.5–4.9], uncemented collar 2.0% [1.2–3.2].

“Cementless” and “cementless short” stems should not be used in patients over 80 years due to the higher revision risk. If cementing should be avoided, “cementless collared” stems seem to be a good alternative combined with a tendency for a lower one year mortality rate.

Abstract

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Abstract

Abstract

Shoulder septic arthritis is uncommon and frequently misdiagnosed, resulting in severe consequences. This study evaluated the demographics, bacteriological profile, antibiotic susceptibility, treatment regimens, and clinical outcomes.

This is a 10-year retrospective observational analysis of 30 patients (20 males and 10 females) who were treated for septic arthritis of the shoulder. The data collecting process utilised clinical records, laboratory archives, and x-ray archives. We gathered demographic information, pre- and post-intervention clinical data, serum biochemical markers, and the results of imaging examinations. All patients had a surgical arthrotomy and joint debridement in the operating room, and specimens were taken for culture and sensitivity testing. The specimens were cultivated for at least seventy-two hours. Shoulder joint ranges of motion, comorbidities, and the presence of osteomyelitis were assessed clinically to determine the outcome. All statistical analyses were conducted using the STATA 17 statistical software. Analysis of correlation between categorical variables was performed using the chi-squared test.

The majority of the study patients were black Africans (97%). The age range of the group was from 8 days to 17 years. At presentation, 33% of patients had a low-grade fever, whereas the majority (60%) had normal body temperature. The average length of symptoms was 3.9 days (ranged from 1 day to 15 days), and the majority of patients had an increased white cell count (83%) and C-reactive protein (98%). There was accumulation of fluid in the joint of all individuals who received shoulder ultrasound imaging. We noted a significant incidence of gram-positive cocci, which were mostly susceptible to first-line antibiotics. Shoulder stiffness affected 63% of patients and chronic osteomyelitis affected 50% of individuals. Neither the severity nor the duration of the symptoms was related to an increased risk of osteomyelitis.

The results of this study revealed that the clinical characteristics and bacterial profile of septic arthritis of the shoulder conform to typical patterns. The likelihood of osteomyelitis and an unfavourable prognosis is considerable.

Abstract

Our understanding of pre-arthritic hip disease has evolved tremendously but challenges remain in categorizing diagnosis, which ultimately impacts choice of treatments and clinical outcomes. This study aims to report patient reported outcome measures (PROMs) comparing four different condition groups within hip preservation surgery by a group of fellowship-trained surgeons.

From 2018 to 2021, 380 patients underwent hip preservation surgery at our center and were classified into five condition groups: dysplasia: 82 (21.6%), femoro-acetabular impingement (FAI): 173 (45.4%), isolated labral tear: 103 (27.1%), failed hip preservation: 20 (5.3%) and history of childhood disease/other: 2 (0.5%). International hip outcomes Tool 12 (IHOT-12), numeric pain score and patient-reported outcomes measurement information system (PROMIS) were collected pre-operatively and at 3 months and 1 year post-operatively, with 94% and 82% follow-up rate respectively.

Arthroscopy (75.5%) was the most common procedure followed by peri-acetabular osteotomy (PAO) (22.4%) and surgical dislocation (2.1%). Re-operation rate were respectively 18.3% (15), 5.8% (10), 4.9% (5), 30% (6) and 0%. There were 36 re-operations in the cohort, 14 (39%) for unintended consequences of initial surgery, 10 (28%) for mal-correction leading to a repeat operation, 8 (22%) progression of arthritis, and 4 (11%) for incorrect initial diagnosis/intervention. Most common re-operations were hardware removal 31% (7 PAO, 3 surgical hip dislocation and 1 femoral de-rotational osteotomy), arthroscopy 31% (11) and arthroplasty 28% (10). All groups had significant improvements in their IHOT-12 as well as PROMIS physical and numerical pain scales, except those with failed hip preservation. Dysplasia group showed a slower recovery.

Overall, this study demonstrated a clear relation between the condition groups, their respective intervention and the significant improvements in PROMs with isolated labral pathology being a valid diagnosis. Establishing tertiary referral centers for hip preservation and longer follow-up is needed to monitor the overall survivorship of these various procedures.

Background and study purpose

Low back pain with no identified underlying cause is categorised as primary musculoskeletal pain by the International Association for the Study of Pain. In April 2021, the National Institute for Care and Excellence (NICE) published updated guidance for the management of primary chronic pain conditions in England. As part of the De-STRESS pain study, we explored the perspectives of GPs on the updated guideline and impact upon clinical practice.

Acetabular retroversion (ARV) is a cause of femoroacetabular impingement leading to hip pain and reduced range of motion. We aimed to describe the radiological criteria used for diagnosing ARV in the literature and report on the outcomes of periacetabular osteotomy (PAO) and hip arthroscopy (HA) in its management.

A systematic review using PRISMA guidelines was conducted on the MEDLINE, CINAHL, EMBASE, COCHRANE database in December 2022. English-language studies reporting outcomes of PAO, or open or arthroscopic interventions for ARV were included.

From an initial 4203 studies, 21 non-randomised studies met the inclusion criteria.

Eleven studies evaluated HA for ARV, with average follow-up ranging from 1 to 5 years, for a cumulative number of 996 patients. Only 3/11 studies identified ARV using AP standardized pelvic radiographs. The most frequent signs describing ARV identified were: Ischial Spine Sign (98% of patients), Posterior Wall Sign (PWS, 94%) and Crossover Sign (COS, 64%); with mean Acetabular Retroversion Index (ARI) ranging from 33% to 35%. 39% of HA patients had all three radiographic signs. Clinically significant outcomes were reached by 33–78% of patients.

Eight studies evaluated PAO for ARV, with a follow-up ranging from 2 to 10 years, for a cumulative number of 379 patients. Five of the eight studies identified ARV using standardized radiographs. ISS, COS and PWS were positive in 54%, 97% and 81% of patients, respectively with 52% of PAO patients having all three radiographic signs. Mean ARI ranged from 36–41%. Clinically significant results were reported in 71%–78% of patients.

The diagnostic criteria for ARV is poorly defined in the literature, and the quality of evidence is low. Studies on HA are more likely to have used lenient diagnostic criteria. It remains difficult to recommend which cases maybe more suitable for treatment by HA rather than PAO.

Aim

The number of periprosthetic joint infections (PJI) is increasing due to ageing population and increasing numbers of arthroplasty procedures and treatment is costly. Aim of the study was to analyze the direct healthcare costs of PJI in Europe for total hip arthroplasties (THA) and total knee arthroplasties (TKA).

Primary malignant bone tumours are a scarce entity with limited population-based data from developing countries. The aim of the study is to investigate the frequency and anatomical distribution of primary malignant bone tumours in a local South African population.

This will be an epidemiological retrospective study. Data will be used of patients that were diagnosed with primary malignant bone tumours over a period of nine years spanning from 1 January 2014 to 31 December 2022. This data will be received from private and government laboratories. Data to be considered are type of primary malignant bone tumours diagnosed, incidence of primary malignant bone tumours over a period of nine years and the most common anatomical sites of primary malignant bone tumours. The rationale behind our study is to assess the frequency of different primary malignant bone tumours in another geographic area of South Africa and to compare these findings to local and international literature. With a projected increase in diagnosis of primary malignant bone tumours in developing countries it is important to have more available data about primary malignant bone tumours from these areas to have a better understanding of these conditions and to understand the impact of the burden they impose on healthcare systems so that management of these conditions can also be improved. Preliminary results show that 23.83% of primary malignant bone tumours occurred in the age group 0–24 years of age, 49.22% in the 25–59 age group and 26.95% in the 60+ age group. The most common tumour that occurred was chondrosarcoma (49.21%) followed by osteosarcoma (41.80%) then Ewing's sarcoma (4,69%) and lastly chordoma (4.30%). From the 256 samples that met the inclusion criteria the five most common anatomical sites were distal femur (63), proximal tibia (41), proximal humerus (38), pelvis (34) and proximal femur (20).

Aim

By gaining insight into the Quality of Life (QoL) status and occurrence of complications, critical facets in the care for patients with Fracture-Related Infection (FRI) can be mitigated and measures can be taken to improve their outcome. Therefore, the aims of this study were to 1) determine the QoL in FRI patients in comparison to non-FRI patients and 2) describe the occurrence of complications in both FRI and non-FRI patients.

There is growing interest in the peri-operative management of patients with indications for hip and knee arthroplasty in the setting of modifiable risk factors such as morbid obesity, type 2 diabetes mellitus, and smoking. A recent survey of the American Association of Hip and Knee Surgeons (AAHKS) found that 95% of respondents address modifiable risk factors prior to surgery. The aim of this study was to poll Australian arthroplasty surgeons regarding their approach to patients with modifiable risk factors.

The survey tool used in the AAHKS study was adapted for use in the Australian context and distributed to the membership of the Arthroplasty Society of Australia via Survey Monkey.

Seventy-seven survey responses were received, representing a response rate of 64%. The majority of respondents were experienced, high volume arthroplasty surgeons. Overall, 91% of respondents restricted access to arthroplasty for patients with modifiable risk factors. Seventy-two percent of surgeons restricted access for excessive body mass index, 85% for poor diabetic control, and 46% for smoking. Most respondents made decisions based on personal experience or literature review rather than hospital or departmental pressures.

Despite differences in healthcare systems, our findings were similar to those of the AAHKS survey, although their responses were more restrictive in all domains. Differences were noted in responses concerning financial considerations for potentially underprivileged populations. The survey is currently being administered by arthroplasty societies in six other countries, allowing comparison of orthopaedic practice across different healthcare systems around the world.

In conclusion, over 90% of Australian arthroplasty surgeons who responded to the survey address modifiable risk factors prior to surgery.

Acetabular component positioning is commonly referenced with the pelvis in the supine position in direct anterior approach THA. Changes in pelvic tilt (PT) from the pre-operative supine to the post-operative standing positions have not been well investigated and may have relevance to optimal acetabular component targeting for reduced risk of impingement and instability. The aims of this study were therefore to determine the change in PT that occurs from pre-operative supine to post-operative standing, and whether any factors are associated with significant changes in tilt ≥13° in posterior direction.

13° in a posterior direction was chosen as that amount of posterior rotation creates an increase in functional anteversion of the acetabular component of 10°.

1097 THA patients with pre-operative supine CT and standing lateral radiographic imaging and 1 year post-operative standing lateral radiographs (interquartile range 12–13 months) were reviewed. Pre-operative supine PT was measured from CT as the angle between the anterior pelvic plane (APP) and the horizontal plane of the CT device. Standing PT was measured on standing lateral x-rays as the angle between the APP and the vertical line. Patients with ≥13° change from supine pre-op to standing post-op (corresponding to a 10° change in cup anteversion) were grouped and compared to those with a <13° change using unpaired student's t-tests.

Mean pre-operative supine PT (3.8±6.0°) was significantly different from mean post-operative standing PT (−3.5±7.1°, p<0.001), ie mean change of −7.3±4.6°.

10.4% (114/1097) of patients had posterior PT changes ≥13° supine pre-op to standing post-op.

A significant number of patients, ie 1 in 10, undergo a clinically significant change in PT and functional anteversion from supine pre-op to standing post-op. Surgeons should be aware of these changes when planning component placement in THA.

Degenerative disc disease (DDD) is a common cause of lower back pain. Calcification of the intervertebral disc (IVD) has been correlated with DDD, and is especially prevalent in scoliotic discs. The appearance of calcium deposits has been shown to increase with age, and its occurrence has been associated with several other disorders such as hyperparathyroidism, chondrocalcinosis, and arthritis. Trauma, vertebral fusion and infection have also been shown to increase the incidence of IVD calcification. Our data indicate that Ca²⁺ and expression of the extracellular calcium-sensing receptor (CaSR) are significantly increased in mild to severely degenerative human IVDs. In this study, we evaluated the effects of Ca²⁺ and CaSR on the degeneration and calcification of IVDs.

Human donor lumbar spines of Thompson grade 2, 3 and 4 through organ donations within 24 hs after death. IVD cells, NP and AF, were isolated from tissue by sequential digestion with Pronase followed by Collagenase. Cells were expanded for 7 days under standard cell culture conditions. Immunohistochemistry was performed on IVD tissue to validate the grade and expression of CaSR. Free calcium levels were also measured and compared between grades. Immunocytochemistry, Western blotting and RT-qPCR were performed on cultured NP and AF cells to demonstrate expression of CaSR, matrix proteins aggrecan and collagen, catabolic enzymes and calcification markers. IVD cells were cultured in increasing concentrations of Ca²⁺ [1.0-5.0 mM], CaSR allosteric agonist (cincalcet, 1 uM), and IL-1b [5 ng/mL] for 7 days. Ex vivo IVD organ cultures were prepared using PrimeGrowth Disc Isolation System (Wisent Bioproducts, Montreal, Quebec). IVDs were cultured in 1.0, 2.5 mM Ca²⁺ or with cinacalcet for 21 days to determine effects on disc degeneration, calcification and biomechanics. Complex modulus and structural stiffness of disc tissues was determined using the MACH-1 mechanical testing system (Biomomentum, Laval, Quebec).

Ca²⁺ dose-dependently decreased matrix protein synthesis of proteoglycan and Col II in NP and AF cells, similar to treatment with IL-1b. (n = 4). Contrarily to IL-1b, Ca²⁺ and cincalcet did not significantly increase the expression of catabolic enzymes save ADAMTS5. Similar effects were observed in whole organ cultures, as Ca²⁺ and cinacalcet decreased proteoglycan and collagen content. Although both Ca²⁺ and cinacalcet increased the expression of alkaline phosphatase (ALP), only in Ca²⁺-treated IVDs was there evidence of calcium deposits in NP and AF tissues as determined by von Kossa staining. Biomechanical studies on Ca²⁺ and cinacalcet-treated IVDs demonstrated decreases in complex modulus (p<0.01 and p<0.001, respectively; n=5), however, only Ca²⁺-treated IVDs was there significant increases stiffness in NP and AF tissues (p<0.001 and p<0.05, respectively; n=3).

Our results suggest that changes in the local concentrations of calcium and activation of CaSR affects matrix protein synthesis, calcification and IVD biomechanics. Ca²⁺ may be a contributing factor in IVD degeneration and calcification.

Aim

Vancomycin is frequently used for bone and joint infections (BJI) because of the main role of Gram-positive bacteria as potential causal agents. It is crucial to achieve optimal vancomycin plasma concentrations since the first day to maximize treatment clinical and microbiological efficacy. The aim was to describe the patients’ profile that are more likely to achieve an optimal pharmacokinetic/pharmacodynamics (PK/PD) vancomycin target in the first therapeutic drug monitoring (TDM) sample.

Since its creation, labral repair has become the preferred method among surgeons for the arthroscopic treatment of acetabular labral tears resulting in pain and dysfunction for patients. Labral reconstruction is performed mainly in revision hip arthroscopy but can be used in the primary setting when the labrum cannot be repaired or is calcified. The purpose of this study was to compare the survival between primary labral repair and labral reconstruction with survival defined as no further surgery (revision or total hip replacement).

Patients who underwent labral repair or reconstruction between January 2005 and December 2018 in the primary setting were included in the study. Patients were included if they had primary hip arthroscopy with the senior author for femoroacetabular impingement (FAI), involving either labral reconstruction or labral repair, and were within the ages of 18 and 65 at the time of surgery. Exclusion criteria included confounding injuries (Leggs Calves Perthes, avascular necrosis, femoral head fracture, etc.), history of unilateral or bilateral hip surgeries, or Tönnis grades of 2 or 3 at the time of surgery. Labral repairs were performed when adequate tissue was available for repair and labral reconstruction was performed when tissue was absent, ossified or torn beyond repair.

A total of 501 labral repairs and 114 labral reconstructions performed in the primary setting were included in the study. Labral reconstruction patients were older (37±10) compared to labral repair (34±11).(p=0.021). Second surgeries were required in 19/114 (17%) of labral reconstruction and 40/501(8%) [odds ratio: 2.3; 95% CI 1.3 to 4.2] (p=0.008). Revision hip arthroscopy were required in 6/114(5%) labral reconstructions and 33/501(6.5%) labral repair (p=0.496). Total hip replacement was required in 13/114 labral reconstructions and 7/501 labral repairs [odds ratio:9.1 95%CI 3.5 to 23] (p=< 0.01). The mean survival for the labral repair group was 10.2 years (95%CI:10 to 10.5) and 11.9 years (98%CI:10.9 to 12.8) in the labral reconstruction group.

Conversion to total hip was required more often following primary labral reconstruction. Revision hip arthroscopy rates were similar between groups as was the mean survival, with both over 10 years. Similar survival was seen in labral repair and reconstruction when strict patient selection criteria are followed.

Aim

The rise of multidrug-resistant bacteria and the decreasing efficacy of antibiotic therapy in successfully treating biofilm-associated infections are prompting the exploration of alternative treatment options. This study investigates the efficacy of different bioactive glass (BAG) formulations - alone or combined with vancomycin - to eradicate biofilm. Further, we study the influence of BAG on pH and osmotic pressure as important factors limiting bacterial growth.

Excessive resident duty hours (RDH) are a recognized issue with implications for physician well-being and patient safety. A major component of the RDH concern is on-call duty. While considerable work has been done to reduce resident call workload, there is a paucity of research in optimizing resident call scheduling. Call coverage is scheduled manually rather than demand-based, which generally leads to over-scheduling to prevent a service gap. Machine learning (ML) has been widely applied in other industries to prevent such issues of a supply-demand mismatch. However, the healthcare field has been slow to adopt these innovations. As such, the aim of this study was to use ML models to 1) predict demand on orthopaedic surgery residents at a level I trauma centre and 2) identify variables key to demand prediction.

Daily surgical handover emails over an eight year (2012-2019) period at a level I trauma centre were collected. The following data was used to calculate demand: spine call coverage, date, and number of operating rooms (ORs), traumas, admissions and consults completed. Various ML models (linear, tree-based and neural networks) were trained to predict the workload, with their results compared to the current scheduling approach. Quality of models was determined by using the area under the receiver operator curve (AUC) and accuracy of the predictions. The top ten most important variables were extracted from the most successful model.

During training, the model with the highest AUC and accuracy was the multivariate adaptive regression splines (MARS) model, with an AUC of 0.78±0.03 and accuracy of 71.7%±3.1%. During testing, the model with the highest AUC and accuracy was the neural network model, with an AUC of 0.81 and accuracy of 73.7%. All models were better than the current approach, which had an AUC of 0.50 and accuracy of 50.1%. Key variables used by the neural network model were (descending order): spine call duty, year, weekday/weekend, month, and day of the week.

This was the first study attempting to use ML to predict the service demand on orthopaedic surgery residents at a major level I trauma centre. Multiple ML models were shown to be more appropriate and accurate at predicting the demand on surgical residents as compared to the current scheduling approach. Future work should look to incorporate predictive models with optimization strategies to match scheduling with demand in order to improve resident well being and patient care.

Mirels’ score predicts the likelihood of sustaining pathological fractures using pain, lesion site, size and morphology. The aim is to investigate its reproducibility, reliability and accuracy in upper limb bony metastases and validate its use in pathological fracture prediction.

A retrospective cohort study of patients with upper limb metastases, referred to an Orthopaedic Trauma Centre (2013–18). Mirels’ was calculated in 32 patients; plain radiographs at presentation scored by 6 raters. Radiological aspects were scored twice by each rater, 2-weeks apart. Inter- and intra-observer reliability were calculated (Fleiss’ kappa test). Bland-Altman plots compared variances of individual score components &total Mirels’ score.

Mirels’ score of ≥9 did not accurately predict lesions that would fracture (11% 5/46 vs 65.2% Mirels’ score ≤8, p<0.0001). Sensitivity was 14.3% &specificity was 72.7%. When Mirels’ cut-off was lowered to ≥7, patients were more likely to fracture (48% 22/46 versus 28% 13/46, p=0.045). Sensitivity rose to 62.9%, specificity fell to 54.6%. Kappa values for interobserver variability were 0.358 (fair, 0.288–0.429) for lesion size, 0.107 (poor, 0.02–0.193) for radiological appearance and 0.274 (fair, 0.229–0.318) for total Mirels’ score. Values for intraobserver variability were 0.716 (good, 95% CI 0.432–0.999) for lesion size, 0.427 (moderate, 95% CI 0.195–0.768) for radiological appearance and 0.580 (moderate, 0.395–0.765) for total Mirels’ score.

We showed moderate to substantial agreement between &within raters using Mirels’ score on upper limb radiographs. Mirels’ has poor sensitivity &specificity predicting upper limb fractures - we recommend the cut-off score for prophylactic surgery should be lower than for lower limb lesions.

The Trauma Triage clinic (TTC) is a Virtual Fracture clinic which permits the direct discharge of simple, isolated fractures from the Emergency Department (ED), with consultant review of the clinical notes and radiographs. This study details the outcomes of patients with such injuries over a four-year period.

All TTC records between January 2014 and December 2017 were collated from a prospective database. Fractures of the radial head, little finger metacarpal, fifth metatarsal, toe phalanges and soft tissue mallet finger injuries were included. Application of the direct discharge protocol, and any deviations were noted. All records were then re-assessed at a minimum of three years after TTC triage (mean 4.5 years) to ascertain which injuries re-attended the trauma clinic, reasons for re-attendance, source of referral and any subsequent surgical procedures.

6709 patients with fractures of the radial head (1882), little finger metacarpal (1621), fifth metatarsal (1916), toe phalanges (920) and soft tissue mallet finger injures (370) were identified. 963 (14%) patients were offered in-person review after TTC, of which 45 (0.6%) underwent a surgical intervention. 299 (4%) re-attended after TTC direct discharge at a mean time after injury of 11.9 weeks and 12 (0.2%) underwent surgical intervention. Serious interventions, defined as those in which a surgical procedure may have been avoided if the patient had not undergone direct discharge, occurred in 1 patient (0.01%).

Re-intervention after direct discharge of simple injuries of the elbow, hand and foot is low. Unnecessary deviations from protocol offer avenues to optimise consumption of service resources.

Aim

Several local antibiotic-eluting drug delivery systems have been developed to treat bacterial bone infections. However, available systems have significant shortcomings, including suboptimal drug-release profiles with a burst followed by subtherapeutic release, which may lead to treatment failure and selection for drug resistance.

Here, we present a novel injectable, biocompatible, in situ-forming depot, termed CarboCells, which can be fine-tuned for the desired antibiotic-release profile. The CarboCell technology has flexible injection properties that allow surgeons to accurately place antibiotic-eluting depots within and surrounding infectious sites in soft tissue and bones. The CarboCell technology is furthermore compatible with clinical image-guided injection technologies.

These studies aimed to determine the therapeutic potential of CarboCell formulations for treatment of implant-associated osteomyelitis by mono- and dual antimicrobial therapy.