Item Response Theory Validation of the Forgotten Joint Score for Persons Undergoing Total Knee Replacement.

BACKGROUND: The Forgotten Joint Score (FJS), a commonly used patient-reported outcome measure, was developed without fully confirming assumptions such as unidimensionality (all items reflect 1 underlying factor), appropriate weighting of each item in scoring, absence of differential item functioning (in which different groups, e.g., men and women, respond differently), local dependence (pairs of items are measuring only 1 underlying factor), and monotonicity (persons with higher function have a higher score). We applied item response theory (IRT) to perform validation of the FJS according to contemporary standards, and thus support its ongoing use. We aimed to confirm that the FJS reflects a single latent trait. In addition, we aimed to determine whether an IRT model could be fitted to the FJS. METHODS: Participants undergoing primary total knee replacement provided responses to the FJS items preoperatively and at 6 and 12 months postoperatively. An exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and Mokken analysis were conducted. A graded response model (GRM) was fitted to the data. RESULTS: A total of 1,774 patient responses were analyzed. EFA indicated a 1-factor model (all 12 items reflecting 1 underlying trait). CFA demonstrated an excellent model fit. Items did not have equal weighting. The FJS demonstrated good monotonicity and no differential item functioning by sex, age, or body mass index. GRM parameters are reported in this paper. CONCLUSIONS: The FJS meets key validity assumptions, supporting its use in clinical practice and research. The IRT-adapted FJS has potential advantages over the traditional FJS: it provides continuous measurements with finer granularity between health states, includes individual measurement error, and can compute scores despite more missing data (with only 1 response required to estimate a score). It can be applied retrospectively to existing data sets or used to deliver individualized computerized adaptive tests. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

A radiological index that influences the outcome following patellofemoral joint arthroplasty: the anterior trochlea offset ratio.

PURPOSE: Although largely successful, patellofemoral joint arthroplasty (PFA) has a less than satisfactory outcome in some patients. It was hypothesized that certain factors can be identified on radiological review that correlate with poor patient reported outcomes following PFA. METHODS: A retrospective cohort review of 369 patients undergoing PFA at our institution between 2005 and 2018 identified 43 "poor outcome" patients with an Oxford Knee Score (OKS) of less than 20 at 2 years follow up. These cases were matched by sex and age with 43 "good outcome" patients who had an OKS above 40 at 2 years post-op. Multiple radiological measurements were performed including anterior trochlea offset ratio (ATOR), component flexion/extension, component varus/valgus, component to bone width ratio and retinacular index. The OKS PROM was the primary outcome of the study. Stepwise logistic regression was performed to analyze the differences in radiological indices between the two groups. RESULTS: Intraclass correlation coefficients for inter-observer and intra-observer reliability were 0.90-0.98 for all indices measured. The only index demonstrating statistical significance between the groups was the ATOR (p = 0.003). The good outcome group had a mean ATOR of 0.19 whereas the poor outcome group had a mean ATOR of 0.24. CONCLUSIONS: Lower ATOR on radiological review was strongly associated with improved outcomes following PFA. The surgeon should therefore take particular care to prevent increasing the anterior offset of the trochlea component when performing PFA. LEVEL OF EVIDENCE: Retrospective cohort study, Level III.

Tibial tuberosity-trochlear groove distance: does it measure up?

Recognized anatomic variations that lead to patella instability include patella alta and trochlea dysplasia. Lateralization of the extensor mechanism relative to the trochlea is often considered to be a contributing factor; however, controversy remains as to the degree this contributes to instability and how this should be measured. As the tibial tuberosity-trochlear groove (TT-TG) is one of most common imaging measurements to assess lateralization of the extensor mechanism, it is important to understand its strengths and weaknesses. Care needs to be taken while interpreting the TT-TG value as it is affected by many factors. Medializing tibial tubercle osteotomy is sometimes used to correct the TT-TG, but may not truly address the underlying anatomical problem. This review set out to determine whether the TT-TG distance sufficiently summarizes the pathoanatomy, and if this assists with planning of surgery in patellar instability. Cite this article: Bone Jt Open 2022;3(3):268-274.

Current concepts in the surgical management of patellar instability.

BACKGROUND: Patellar instability is a common condition, and recurrent instability can be highly disabling. It is important to understand the patho-anatomy of patellar instability in order to treat it effectively, with the trochlear shape, patellar height and the integrity of the medial retinaculum being the most important factors in determining the risk of ongoing instability. CLINICAL ASSESSMENT AND RADIOGRAPHIC ASSESSMENT: Clinical assessment is based around correct diagnosis of instability, identification of at risk features and an assessment of neuromuscular control and factors that may affect the potential for rehabilitation before or after surgery. Radiology is important to assess features predisposing to instability and to determine the best treatment plan for each individual. TREATMENT: There are a range of surgical options for the treatment of patellar instability and these should be chosen based on an each patients individual patho-anatomy. Lateral release is not recommended as a treatment for patellar instability. Medial patello-femoral ligament reconstruction, tibial tubercle distalisation, trochleoplasty or occasionally tibial or femoral osteotomies for correction of rotational or coronal plane mal-alignment may all be used either individually or in combination. High quality physiotherapy is an essential part of post-operative management and should address the whole of the kinetic chain, working on strength and control of the lower limbs to optimise balance and movement patterns in order to achieve the best results.

Adoption of a novel surgical innovation into clinical practice: protocol for a qualitative systematic review examining surgeon views.

INTRODUCTION: Efficient adoption of clinically effective novel surgical innovations has great potential benefits for patients. Factors affecting the adoption of surgical innovation are not well understood and proposed models of adoption do not accurately correlate with historical evidence. This protocol is for a systematic review that aims to identify the qualitative evidence relating to surgeon views regarding the adoption of novel surgical innovation into clinical practice. METHODS AND ANALYSIS: A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance will be performed. Two independent reviewers will search the following databases: MEDLINE, Embase, Science Direct, Scopus, Web of Science and the Cochrane Library of Systematic Reviews. Inclusion criteria are studies which report on the views of surgeons who adopt a novel surgical innovation into clinical practice. Each article will be screened for inclusion and assessed according to a Critical Appraisal Skills Programme tool. Data will be synthesised and analysed according to thematic analysis. Given the anticipated yield of a small heterogeneous body of evidence meeting the eligibility criteria for the review, a narrative-based summary is planned. ETHICS AND DISSEMINATION: This review does not require formal ethical approval as it does not involve direct patient contact or patient-identifiable data. The results of this review will be published in a peer-reviewed journal and presented at relevant conferences. The results will also inform an empirical qualitative study exploring surgeon and other stakeholder views regarding the introduction of novel surgical technology and procedures into clinical practice. PROSPERO REGISTRATION NUMBER: CRD42017076715.

The Journey patellofemoral joint arthroplasty: A minimum 5year follow-up study.

BACKGROUND: The Journey patellofemoral joint arthroplasty (PFA) was designed to improve patient outcomes following surgical management of patellofemoral joint osteoarthritis. It is based on the asymmetric trochlear geometry of the Genesis II total knee arthroplasty, with Oxinium components, to provide a reliable treatment option in an often young, high demand group of patients. METHODS: We report the minimum five year functional outcome and survivorship of the Journey PFA performed at our institution between October 2005 and September 2009. RESULTS: A total of 101 Journey PFAs were implanted in 83 patients, and we have complete outcomes for 90 implants (89%). There were 80 implants in female patients, and the mean age at time of surgery was 60years (26 to 86). The median Oxford Knee Score (0 to 48) improved from 18 to 30, and median Western Ontario and McMaster University Osteoarthritis Short Form Index (0 to 60) improved from 22 to 35. There were a total of 12 revisions, with mean time to revision 50months (10 to 99). CONCLUSIONS: The Journey PFA gives a good medium-term functional outcome with 88% survivorship at a mean of seven years. This is the largest study of Journey PFA in the literature, and it provides a reliable option for patients with isolated patellofemoral joint osteoarthritis when arthroplasty is considered.

Spontaneous locking of the knee after anterior cruciate ligament reconstruction as a result of a broken tibial fixation device.

The Intrafix device (DePuy Mitek, Raynham, MA) is one of a number of recently developed products whose aim is to improve fixation of quadrupled hamstring grafts when used for anterior cruciate ligament reconstruction. We present a case of failure and intra-articular migration of the sleeve of an Intrafix device causing locking of the knee 10 weeks after anterior cruciate ligament reconstruction. We were unable to identify the cause of the failure or migration of the device. Rehabilitation had been progressing normally and without incident. The broken fragments were removed arthroscopically, and the reconstruction was found to be intact and healing well. Presumably, the device retained enough mechanical function to allow healing to progress, despite failure of the sleeve. This is, to our knowledge, the first reported case of such an event occurring with the new generation of hamstring graft fixation devices.

Standardised proformas improve patient handover: Audit of trauma handover practice.

BACKGROUND: The implementation of the European Working Time Directive has meant the introduction of shift patterns of working for junior doctors. Patient handover between shifts has become a necessary part of practice in order to reduce the risk of medical errors. Data handed over between shifts are used to prioritise clinical jobs outstanding, and to create theatre lists. We present a closed-loop audit of handover practice to assess whether standardised proformas improve clinical data transfer between shifts during handover in our Orthopaedic Unit. METHODS: We collected data handed over between shifts for a period of one week at our department. The data were in the form of hand written data on plain paper used to assist verbal handover. Data were analysed and a standardised handover sheet was trialled. After feedback from juniors the sheet was revised and implemented. A re-audit, of handover data, was then undertaken using the revised standardised proforma during a period of 1 week. RESULTS: Forty-eight patients were handed over in week 1 while 55 patients were handed over during re-audit. The standardised proformas encouraged use of pre-printed patient labels which contained legible patient identifiers, use of labels increased from 72.9% to 93.4%. Handover of outstanding jobs increased from 31.25% to 100%. Overall data handed over increased from 72.6% to 93.2%. Handover of relevant blood results showed little improvement from 18.8% to 20.7% CONCLUSION: This audit highlights the issue of data transfer between shifts. Standardised proformas encourage filling of relevant fields and increases the data transferred between shifts thereby reducing the potential for clinical error cause by shift patterns.