Background

While the human embryonic, foetal and juvenile intervertebral disc (IVD) is composed of large vacuolated notochordal cells, these morphologically distinct cells are lost with skeletal maturity being replaced by smaller nucleus pulpous cells. Notochordal cells are thought to be fundamental in maintaining IVD homeostasis and, hence, their loss in humans may be a key initiator of degeneration, leading ultimately to back pain. Therefore, it is essential to understand the human notochordal cell phenotype to enable the development of novel biological/regenerative therapies.

Antibiotic-loaded bone cements are used to decrease occurrence of bone infections in cemented arthroplasties and actually being considered as a more cost-effective procedure when compared to cementless implants [1]. However, considering the challenge of treating device-associated infections there is a reduced number of formulations in the market. Response from the industry to medical need is still slow considering the rapid change in the infecting microbial profile and the emergence of multiresistant strains [2]. In this context, the aim of the work is to evaluate the role of lactose (L), as a porogen, on the antibiotic release from bone cement (BC). Levofloxacin (Lev) and minocycline (M) were the selected antibiotics to be individually loaded into BC due to their low cost and potential application in bone infections [3,4].

Two types of matrices were prepared: 1) Loaded with 2.5% of antibiotics (controls) and 2) Loaded with 10% lactose and 2.5% antibiotic. In vitro drug release and microbiological tests against representative strains causative of bone infections were assessed.

Lactose significantly increased the release of both antibiotics. Complete minocycline release after one-week was observed (Fig.1A). Also, lactose increased 3.5-fold the levofloxacin released from BC (Fig.1B).

Furthermore, microbiological studies showed that no interaction was observed between lactose and antibiotic as no decrease in drugs antimicrobial activity was observed (Table 1).

Considering the results, L-BC matrix appears to be a valuable alternative to available formulations. Future work will include testing other antibiotics as well as mixtures of drugs.

Fundação para a Ciência e Tecnologia (Portuguese government) for financial support: EXCL/CTM-NAN/0166/2012 and strategic project PEst-OE/SAU/UI4013/2011.

Because life expectancy is increasing, the number of primary knee arthroplasties performed is projected to increase 673% by 2030, according to Westrich et al. Also, Toulson et al. in a recent study predict that the incidence of deep infection associated with primary total knee arthroplasty ranges from 1% to 2%. Periprosthetic knee infection is one of the most dramatic and difficult to manage complications following total knee arthroplasty. Therefore, periprosthetic knee infection will continue to be a significant complication and an economic burden in the future. Our objective was to identify the risk factors that may provide greater likelihood of infection and thus select high-risk patients and to take maximum prevention strategies.

Case-control study, between infected and non infected patients, undergoing primary total knee arthroplasty between January 2008 and January 2013. The risk factors evaluated were: duration of hospital stay, surgery duration, prophylactic antibiotics and timing for administration, volume of blood transfusion, autologous blood recovery system use, anesthetic technique, ASA classification, Diabetes Mellitus, Obesity (BMI>30), immunosuppression and history of any infection in the month preceding surgery. The presence of infection was defined by the criteria of the Center for Disease Control for Nosocomial Surgical Site Infections1. Statistical analysis IBM SPSS Statistics 20 (Fisher's exact test, Mann-Whitney U test and Student's t-test). Statistical significance for p ≤ 0.05.

We evaluated 540 patients with a mean follow-up of 56 months. We identified 21 deep infections (3,8%), and 35 superficial wound infections and found a positive correlation between infection and obesity (p <0.01), immunosuppression (p <0.01), volume of blood transfusion (p=0.02), history of any infection in the month preceding surgery (p <0.01). We found a negative correlation with the use of a autologous blood recovery system (p <0.01). Other factors, commonly referred in the literature, showed no association or did not reach statistical significance.

The incidence of periprosthetic knee infection after primary total knee arthroplasty stays high. The presence of obesity, immunosuppression, blood transfusion, history of any infection in the month preceding surgery were identified as significant risk factors for infection to occur. The identification, modification or eviction of the risk factors implied are essential to reduce and prevent infection in arthroplasty.

The purpose of this study is to report a unique overgrowth syndrome and discuss the insights into the complex orthopaedic management.

Written consent to report this case was granted. The patient's condition, wrongly diagnosed as Proteus syndrome, is characterised by a genetic mutation in PIK3CA, a critical regulator of cell growth. This lead to unregulated cellular division of fibroblasts isolated to the lower limbs. The legs weighed 117 kg, with a circumference of >110 cm. In addition to lower limb overgrowth, numerous musculoskeletal and organ pathologies have been encountered since birth requiring treatment from a wide variety of healthcare specialists and basic scientists. At 32 years, the patient developed septicaemia secondary to an infected foot ulcer. Amputation had been discussed in the elective setting, however the presence of sepsis expedited surgery. The above knee amputation took 9 hours and four assistants including a plastic surgeon. A difficult dissection revealed a deep subcutaneous fatty layer that integrated with deep muscle, massive hypertrophy of cutaneous nerves and the sciatic nerve and ossification within the distal quarter of the quadriceps muscles requiring osteotomy. The lower limb osteology was grossly aberrant. The size of the amputated limb did not permit use of a tourniquet and cell salvage reintroduced 10.5 litres of blood with a further 6 units of red cells intra-operatively. The leg stump successfully took to a split-skin graft. A unique phenomenon was witnessed post-operatively whereby the stump continued to grow due to upregulation of fibroblasts secondary to trauma. Targeted genetic therapies have been successfully developed to suppress this stump growth.

This unique and unclassified overgrowth syndrome was caused by a mutation in the PIK3CA gene. Orthopaedic management of the oversized limb was complex requiring multiple surgeons and prolonged general anesthetic. A multi-disciplinary approach to this condition is required for optimizing outcomes in these patients.

Mesenchymal stem-cell based therapies have been proposed as novel treatments for intervertebral disc degeneration, a prevalent and disabling condition associated with back pain. The development of these treatment strategies, however, has been hindered by the incomplete understanding of the human nucleus pulposus phenotype and by an inaccurate interpretation and translation of animal to human research. This review summarises recent work characterising the nucleus pulposus phenotype in different animal models and in humans and integrates their findings with the anatomical and physiological differences between these species. Understanding this phenotype is paramount to guarantee that implanted cells restore the native functions of the intervertebral disc.

Cite this article: Bone Joint Res 2013;2:169–78.

INTRODUCTION

Patellar tendon (PT) autograft is an excellent choice repairing anterior cruciate ligament (ACL) ruptures. Published studies testing the biomechanical characteristics after plasty usually refer to grafts with 10mm wide. The thickness of PT and geometry of the patella have been overlooked.

The purpose of this study was to understand the geometry of PT and patella in our population, regarding their use in Bone - Patellar Tendon - Bone (BTB) technique, in order to evaluate their biomechanical efficiency and study their relationship with anthropometric parameters.

Introduction

Interest in platelet-derived growth factors has been increasing as an adjunct in surgical techniques for tissue repair. Its use in ligament injuries repair has been studied mainly in animals. The authors intend to study growth factors influence in ACL repair using BTB graft.

Radial osteotomy is currently advocated for patients with Lichtman’s stages II and IIIA of Kienböck’s disease; its place in the treatment of patients with stage IIIB disease remains controversial. The purpose of this study was to evaluate the medium-term results of this procedure and to compare the outcome in patients with stage IIIB disease and those with earlier stages (II and IIIA). A total of 18 patients (18 osteotomies) were evaluated both clinically and radiologically at a mean follow-up of 10.3 years (4 to 18). Range of movement, grip strength and pain improved significantly in all patients; the functional score (Nakamura Scoring System (NSSK)) was high and self-reported disability (Disabilities of Arm, Shoulder and Hand questionnaire) was low at the final follow-up in all patients evaluated. Patients with stage IIIB disease, however, had a significantly lower grip strength, lower NSSK scores and higher disability than those in less advanced stages. Radiological progression of the disease was not noted in either group, despite the stage. Radial osteotomy seems effective in halting the progression of disease and improving symptoms in stages II, IIIA and IIIB. Patients with less advanced disease should be expected to have better clinical results.

Purpose of the study: Proximal fractures of the humerus account for 10% of fractures in persons aged over 65 years. There is no optimal treatment. The goal of surgery is to restore joint congruency, preserve vascular supply, and allow functional recovery. We describe the results obtained with a surgical technique designed to meet these goals.

Material and methods: Fifteen 3-fragment fractures of the proximal humerus were treated with transosseous suture. Mean age of patients was 58 years. Eighty-six percent of the patients were female. Follow-up was 18 months on average. The patients were placed in a lounge chair position for the deltopectoral or transdeltoid approach. For this type of fracture, the humeral head is displaced medially or laterally, so that care must be taken to ensure the realignment in the sagittal and coronal planes. The DASH and Constant scores were noted for the operated and non-operated shoulders. Signs of bone healing were noted on the plain x-rays.

Results: The mean DASH was 12, mean Constant score for the operated shoulder was 80 versus 90 for the other shoulder. The mean neck-shaft angle was 139°. There was one case of lost reduction but with a good final result. There was one case converted to arthroplasty.

Discussion: This technique is in line with the current trend for biological preservation minimising the aggression to the humeral head blood supply. There was no risk of migration with the fixation material used and no need to remove implants.

Conclusion: Transosseous suture of proximal fractures of the humerus is a mini-invasive method which provides good functional results avoiding voluminous metal implants, known to be costly and source of complications. The incidence of avascular necrosis of the humeral head is low, in agreement with the international literature.

Cervical Spondylotic Mielopathy (CSM) is the most common cause of spinal cord dysfunction in the adult population. Treatment implies surgical decompression as soon as possible after the diagnosis. In this study the authors present the long term results of minimal 10 years follow up of a prospective study of 98 patients that underwent anterior decompression and arthrodesis surgery for CSM.

Patients that underwent surgery for CSM between January 1990 and December 1994 were evaluated for sex, age, number of levels operated, functional evaluation with Nurick Scale pre operatively, 1 year after surgery and at the final the revision that took place in 2007 and 2008, evidence of consolidation and complications. All the patients were operated by anterior approach. T-Student Test was performed with SPSS for statistical analysis.

99 patients were evaluated during the study, 73 male, 26 female, with a mean age of 56, 6 years (42–86) and mean follow up time of 14,4 years. 3 patients died in the immediate pos op period, 1 in the first year, 8 during the 15 year evaluation period. 16 patients were operated for 1 level, 22 for two levels, 36 for 3 levels and 22 for four levels (mean on 2,7±1,0 levels for patient).

Pre op Nurick was 3,8±0,9. There was a significant improvement in neurological condition after one year surgery (Nurick 2,2±1,1; p< 0,001), and between pre op and final evaluation (2,3±1,2; p< 0,001). The degradation between the first year and the final evaluation was statistically significant (p=0,004).

There was a strong correlation between age and the number of operated levels (r=0,391, p=0,01), age and initial neurologic status (r=0,238, p=0,05), initial neurological status and number of operated levels (r=0,251, p=0,05) and sex and number of operated levels, with women being operated for more levels (r=0,208, p=0,05). There was also e stronger neurological deterioration between year 1 and year 15 in young patients when compared to older ones (r=0,250, p=0,05). There is a strong clinical relation between first year recuperation and final recuperation (r=0,838, p=0,01). There was a 100% rate of consolidation.

Surgical treatment for decompression and arthrodesis is considered for us the best option for the treatment of CSM in terms of improvement of pain, alignment and neurological function. A significant neurological improvement comes from surgery, and despite a significant clinical deterioration between the first year and the final evaluation, the benefits of surgery are still evident 15 years after, with a better neurological status when compared to the pre operative period.

Treatment of patellar instability in adolescents is controversial. Some investigators have advocated early repair of the medial structures, whereas others have treated this injury nonoperatively. The medial patellofemoral ligament, is a primary restrictor and stabilizer of the patella, and has acquired a significant role in the treatment of instability in children and adolescents.

The authors present a prospective study of 39 consecutive patients (45 knees), without physeal closure, who underwent plasty of the medial patellofemoral ligament for the treatment of symptomatic patellofemoral instability with autologous Gracilis tendon, according to Chassaing’s technique. There were 26 female and 13 male patients with an average age of 15, 9 years. Mean follow-up was 44 months (6–65). All patients presented with clinical evident patellar tilt. This population presented a TA-GT within a normal range (12+/− 5 mm), but presented in 80% of cases a trochlear dysplasia

Clinical functional results were evaluated using the Kujala scale. Arthroscopic evaluation was systematically performed searching for intra articular injuries or patellar tilt. Early rehabilitation protocols were used in all cases.

At the last follow up evaluation, 90% of the patients presented good or very good results. Kujala Score was 84, 5 +/−9,7 after surgery compared with 54,9+/−11,8 before surgery (p< 0,0001). There were 3 minor complications: 2 hematomas and 1 superficial infection that resolved without complications.

Four patients kept complaining of residual anterior knee pain as result of patellar chondropathy that was diagnosed intra operatively. Three patients complained of graft donor site pain. One patient presented with a patellar dislocation three years after the surgery, and two patients still present clinical instability two years after the procedure. There was no stiffness in the knee in any patient.

The technique presented in this study has allowed very good clinical results, with few complications, using a small incision to reconstruct in an isometric fashion, this important patellar stabilizer.

Our objective is to perform a prospective study on the efficiency and durability of pain reduction through percutaneous PMMA vertebroplasty in patients with vertebral osteoporotic fractures.

We started in March 2002, and up to January 2005 we have performed this technique in 43 patients, 42 female and 1 male, with osteoporotic vertebral fractures. We performed a total of 56 vertebroplasties, 36 lumbar and 20 thoracic. The majority is for the thoracolumbar junction. Patient age went from 56 to 85, with an average of 70,7 years.

Cryteria for inclusion in this study have been the following:patients with osteoporosis, preferably with one or two collapsed vertebral bodies, with intractable pain for over 3 months. Exclusion cryteria have been: infection, blood coagulation deficits and mieloradicular compression. Relative exclusion criteria are Fractures over 70% body collapse, Posterior wall fragmentation and Young patient fracture with no prior disease.

We perform our PV under local anesthaesia with sedation and in a lateral decubitus position. We preferably use a parapedicular approach for both thoracic and lumbar fractured vertebrae.

The material we prefer are the LP2 system or the LCO and we chose Exolent spine for PMMA.

We follow a protocol that consists in:bed rest for 2 hours, allowing the patient to sit and have small walks afterwards;Dismissal the following day, with a mild analgesic for the effects of the skin incision;Maintain drug treatment for osteoporosis;Revision on the 2nd and 7th day;New revision at 3, 6 and 12 months.

Evaluation of the results was made by defining a pain score: Score 1 corresponds to minor or no improvement in pain.

Score 2 corresponds to a medium improvement in pain, with 25 to 50% less drugs required.

Score 3 corresponds to a better improvement in pain, with 75 % less drugs required.

Score 4 corresponds to complete relief of pain. In our revision, we had a minimum follow-up of 12 months, maximum of 44, and an average of 28 months. We have observed the following results:

- 2 patients with score 1

We can resume this by stating that 90 % of the patients had a relief in pain, and a good result was observed in 75 %.

We have had some complications, which consisted in:

- PMMA leakage into the disc in 1 case

In conclusion, and up to now, we have obtained pain reduction in 90% of the cases; we have prevented collapse of the treated vertebrae, and we have not had collapse of any adjacent vertebrae.

It is a technique that may have complications, but results depend on a correct selection of patients.