A proportion of patients with hip and knee prosthetic joint infection (PJI) undergo multiple revisions with the aim of eradicating infection and improving quality of life. The aim of this study was to describe the microbiology cultured from multiply revised hip and knee replacement procedures to guide antimicrobial therapy at the time of surgery. Consecutive patients were retrospectively identified from databases at two specialist orthopaedic centres in the United Kingdom between 2011 and 2019. Patient were included who had undergone repeat revision total knee replacement (TKR) or total hip replacement (THR) for infection, following an initial failed revision for infection.Introduction
Patients and Methods
This study assesses the ability of the JS-BACH classification of bone infection to predict clinical and patient-reported outcomes in prosthetic joint infection (PJI). Patients who received surgery for suspected PJI at two specialist bone infection centres within the UK between 2010 and 2015 were classified using the JS-BACH classification into either ‘uncomplicated’, ‘complex’ or ‘limited options’. All patients were classified by two clinicians blinded to outcome, with any discrepancies adjudicated by a third reviewer. At the most recent follow-up, patients were assessed for (i) any episode of recurrence since the index operation and (ii) the status of the joint. A Cox proportional-hazard model assessed significant predictors of recurrence following the index procedure. Patient-reported outcomes included the EuroQol EQ-5D-3L index score and the EQ-visual analogue score (VAS) at 0, 14, 42, 120 and 365 days following the index operation.Aim
Method
The aim of this study is to report the 30 day COVID-19 related morbidity and mortality of patients assessed as SARS-CoV-2 negative who underwent emergency or urgent orthopaedic surgery in the NHS during the peak of the COVID-19 pandemic. A retrospective, single centre, observational cohort study of all patients undergoing surgery between 17 March 2020 and 3May 2020 was performed. Outcomes were stratified by British Orthopaedic Association COVID-19 Patient Risk Assessment Tool. Patients who were SARS-CoV-2 positive at the time of surgery were excluded.Introduction
Method
Antibiotic loaded absorbable calcium sulphate beads (ALCSB) are an increasingly popular adjunct in the treatment of musculoskeletal infections including osteomyelitis and peri-prosthetic joint infections (PJI). Limited data exist regarding the clinical indications and biochemical outcomes of ALCSB in PJI cases. To determine the proportion of organisms that were sensitive to the gentamicin and vancomycin that we add to the ALCSB as a part of our treatment protocol and to determine the prevalence of postoperative hypercalcaemia when used for treatment of hip and knee DAIR (debridement and implant retention) and revision arthroplasty for PJI.Introduction
Aims
Despite recent advances in the diagnosis of periprosthetic joint infection(PJI), identifying the infecting organism continues to be a challenge, with up to a third of PJIs reported to have negative cultures. Current molecular techniques have thus far been unable to replace culture as the gold standard for isolation of the infecting pathogen. Next- generation sequencing(NGS) is a well-established technique for comprehensively sequencing the entire pathogen DNA in a given sample and has recently gained much attention in many fields of medicine. Our aim was to evaluate the ability of NGS in identifying the causative organism(s) in patients with PJI. After obtaining Institutional Review Board approval and informed consent for all study participants, samples were prospectively collected from 148 revision total joint arthroplasty procedures (83 knees, 65 hips). Synovial fluid, deep tissue and swabs were obtained at the time of surgery and shipped to the laboratory for NGS analysis (MicroGenDx). Deep tissue specimens were also sent to the institutional laboratory(Thomas Jefferson University Hospital) for culture. PJI was diagnosed using the Musculoskeletal Infection Society(MSIS) definition of PJI. Statistical analysis was performed using SPSS software.Introduction
Methods
A number of orthopaedic strategies have been described for limb salvage following periprosethic joint infection (PJI). However, this is often only possible with concomitant soft tissue reconstruction in the form of flap coverage. The purpose of this study was to determine the long-term clinical outcome of patients who underwent pedicled gastrocnemius flap coverage as part of their treatment for knee PJI. We performed a retrospective review of all patients undergoing gastrocnemius muscle transfer with split thickness skin grafting as part of their treatment for knee PJI at a tertiary referral centre between 1994 and 2015. Data recorded included patient characteristics, orthopaedic procedure, microbiology result and antimicrobial management. Outcome measures included flap failure, infection recurrence, amputation, functional outcome (Oxford knee score; OKS) and mortality.Aim
Method
The optimal correction of the weight bearing line during High Tibial Osteotomy has not been determined. We used finite element modelling to simulate the effect that increasing opening wedge HTO has on the distribution of stress and pressure through the knee joint during normal gait. Subject-specific models were developed by combining geometry from 7T MRI scans and applied joint loads from ground reaction forces measured during level walking. Baseline stresses and pressures on the articulating proximal tibial cartilage and menisci were calculated. Progressive osteotomies were then simulated to shift the weight-bearing line from the native alignment towards/into the lateral compartment (between 40 – 80% of medial-lateral tibial width). Changes in calculated stresses and pressures were recorded. Both stress and pressure decreased in the medial compartment and increased in the lateral compartment as increasingly valgus osteotomies were simulated. The models demonstrated a consistent “safe zone” for weight bearing line position at 50%-65% medial-lateral tibial width, outside of which compartment stresses and pressures substantial increased. This study suggests a safe correction zone within which a medial opening wedge HTO can be performed correcting the WBL to 55% medio-lateral width of the tibia.
Endoprosthetic replacement (EPR) is an available option for the management of massive bone loss around failed knee implants. The aim of this study was to determine the results of knee EPRs performed for non-tumour indications. Since 2007, 85 EPRs were performed for in a single tertiary centre by seven surgeons. Mean age at surgery was 73.5 years (range:35–95) with infection as the most common indication (49%), followed by aseptic loosening (18%), complex primary replacement (16%), fracture (15%) and mechanical failure (2%). Mean follow up was 4 years (range:1–9). Functional outcome was determined using the Oxford Knee Score (OKS). At follow-up, 21 patients were deceased and 2 lost to follow-up. Complication rate was 19%. Of the 7 infected cases, 6 were treated with DAIR (debridement, antibiotics, and implant retention) and one underwent above knee amputation. Four of the patients undergoing DAIR were cleared of infection and 2 are on long-term antibiotics. Accounting for implant revision, loss to follow-up and those on long-term antibiotics as failures, 5-year survival was 89% with an average OKS of 25 (SD=10). This mid-term study shows that distal femur EPR is a valuable option for the increasing burden of complex revision knee surgery
To assess the influence of route of antibiotic administration on patient-reported outcome measures (PROMS) of individuals treated for hip and knee infections in the OVIVA multi-centre randomised controlled trial. This study was designed to determine whether oral antibiotic therapy is non-inferior to intravenous (IV) therapy when given for the first six weeks of treatment for bone and joint infections. Of the 1054 participants recruited from 26 centres, 462 were treated for periprosthetic or native joint infections of the hip or knee. There were 243 participants in the IV antibiotic cohort and 219 in the oral cohort. Functional outcome was determined at baseline through to one year using the Oxford Hip/Knee Score (OHS/OKS) as joint-specific measures (0 the worse and 48 the best). An adjusted quantile regression model was used to compare functional outcome scores.Aim
Method
Advocates of Debridement-Antibiotics-and-Implant-Retention (DAIR) in hip peri-prosthetic joint infection (PJI) argue that a procedure not disturbing a sound prosthesis-bone interface is likely to lead to better survival and functional outcome compared to revision. However, no evidence supports this. This case-control study's aims were to compare outcome of DAIRs for infected 1° total hip arthroplasty (THA) with outcomes following 1° THA and 2-stage revisions of infected 1° THAs. We retrospectively reviewed all DAIRs, performed for confirmed infected 1° THR (DAIR-Group, n=80), in our unit between 1997–2013. Data recorded included patient demographics, medical history, type of surgery and organism identified. Outcome measures included complications, mortality, implant survivorship and functional outcome using the Oxford Hip Score (OHS). Outcome was compared with 2 control groups matched for gender and age; a cohort of 1° THA (1°-THA-Group, n=120) and a cohort of 2-stage revisions for infection (2-Stage-Revision-Group, n=66).Aim
Method
The burden of peri-prosthetic joint infection (PJI) following hip and knee surgery is increasing. Endoprosthetic replacement (EPR) is an option for management of massive bone loss resulting from infection around failed lower limb implants. To determine clinical outcome of EPRs for treatment of PJI around the hip and knee joint.Introduction
Aims
Current work-hour restrictions and cost pressures have highlighted the limitations of apprenticeship-based learning, and led to the development of alternative methods to improve the skills of orthopaedic trainees outside of the clinical environment. These methods include using synthetic bones and simulators in the laboratory setting. Educational theory highlights the importance of context for effective learning, yet full-immersion simulation facilities are prohibitively expensive. This study explored the concept of contextualised training day in trauma & orthopaedics. Fifteen novice surgeons provided feedback after completing three teaching modules: OSCE-style Problem-based Learning of Orthopaedic Trauma in the Fracture Clinic Setting, utilising an actor and radiographs to teach history, examination, diagnostic and management skills The positioning, preparing and draping of a patient, and Examination under anaesthesia (EUA) for arthroscopic knee surgery, utilising an operating table and theatre equipment to teach procedural and examination skills Simulator based training for diagnostic shoulder and knee arthroscopy; and Bankart repair, utilising arthroscopic stack and synthetic joint models to develop arthroscopic motor skill and procedural knowledgeIntroduction
Methods
Restrictions placed on the working hours of doctors have led to increasing time-pressures on surgical training. Consequently, there has been growing interest in developing new techniques to teach and assess technical skills. The primary aim of this study was to determine whether a novel set of visual parameters assessing visuospatial ability, fine motor dexterity and gaze control could objectively distinguish between varying levels of arthroscopic experience. The secondary aim was to evaluate the correlations between these new parameters and previously established technical skill assessment methods. 27 subjects were divided into a “novice” group (n=7), “trainee” group (n=15) and expert group (n=5) based on previous arthroscopic experience. All subjects performed a diagnostic knee arthroscopy task on a simulator. Their performance was assessed using new simple visual parameters that included “prevalence of instrument loss,” “triangulation time” and “prevalence of look downs”. In addition, performance was also evaluated using previously validated technical skill assessment methods (a global rating scale and motion analysis).Introduction
Methods
Motion analysis is a validated method of assessing technical dexterity within surgical skills centers. A more accessible and cost-effective method of skills assessment is to use a global rating scale (GRS). We aimed to perform a validation experiment to compare an arthroscopic GRS against motion analysis for monitoring orthopaedic trainees learning simulated arthroscopic meniscal repairs. An arthroscopic meniscal repair task on a knee simulator was set up in a bioskills laboratory. Nineteen orthopaedic trainees with no experience of meniscal repair were recruited and their performance assessed whilst undertaking a standardized meniscal repair on 12 occasions. An arthroscopic GRS, assessing parameters such as “depth perception,” “bimanual dexterity,” “instrument handling,” and “final product analysis” was used to evaluate technical skill. Performance was assessed blindly by watching video recordings of the arthroscopic tasks. Dexterity analysis was performed using a motion analysis tracking system which measured “time taken,” “total path length of the subject's hands,” and “number of hand movements”.Introduction
Methods
