Aims. This study aimed to investigate the role of quantitative histological analysis in the diagnosis of fracture-related infection (FRI). Patients and Methods. The clinical features, microbiology culture results, and histological analysis in 156 surgically treated nonunions were used to stratify the likelihood of associated infection. There were 64 confirmed infected nonunions (one or more confirmatory criteria: pus, sinus, and bacterial growth in two or more samples), 66 aseptic nonunions (no confirmatory criteria), and 26 possibly infected nonunions (pathogen identified from a single specimen and no confirmatory criteria). The histological inflammatory response was assessed by average neutrophil polymorph (NPs) counts per high-power field (HPF) and compared with the established diagnosis. Results. Assuming a cut-off of over five neutrophils per high-power field to diagnose septic nonunion, there was 80% sensitivity and 100% specificity (accuracy 90%). Using a cut-off of no neutrophils seen in any high-power field to diagnose aseptic nonunion, there was a sensitivity of 85% and a specificity of 98% (accuracy 92%). Conclusion. Histology can be used in a bimodal fashion as a diagnostic test for FRI. The presence of more than five NPs/HPF had a positive predictive value for infected nonunion of 100%, while the complete absence of any NPs is almost always indicative of an aseptic nonunion (positive predictive value of 98%). Cite this article: Bone Joint J 2018;100-B:966–72

Aims. The aim of this study was to evaluate the diagnostic value of preoperative serum CRP, white blood cell count (WBC), percentage of neutrophils (%N), and neutrophil to lymphocyte ratio (NLR) when using the fracture-related infection (FRI) consensus definition. Methods. A cohort of 106 patients having surgery for suspected septic nonunion after failed fracture fixation were studied. Blood samples were collected preoperatively, and the concentration of serum CRP, WBC, and differential cell count were analyzed. The areas under the curve (AUCs) of diagnostic tests were compared using the z-test. Regression trees were constructed and internally cross-validated to derive a simple diagnostic decision tree. Results. Using the FRI consensus definition, 46 patients (43%) were identified as infected. Sensitivity, specificity, and AUC of CRP were 67% (95% confidence interval (CI) 52% to 80%), 61% (95% CI 47% to 74%), and 0.64 (95% CI 0.54 to 0.74); of WBC count were 17% (95% CI 9% to 31%), 95% (95% CI 86% to 99%), and 0.57 (95% CI 0.50 to 0.62); of %N 13% (95% CI 6% to 26%), 87% (95% CI 76% to 93%), and 0.50 (95% CI 0.43 to 0.56); and of NLR 28% (95% CI 17% to 43%), 80% (95% CI 68% to 88%), and 0.54 (95% CI 0.46 to 0.63), respectively. A better performance of serum CRP was shown in comparison to the leucocyte count (p = 0.006), %N (p < 0.001), and NLR (p = 0.001). A statistically lower serum CRP level was shown in patients with an infection caused by a low virulence microorganism in comparison to high virulence bacteria (p = 0.008). We found that a simple decision tree approach using only low serum neutrophils (< 3.615 × 10. 9. /l) and low CRP (< 2.45 mg/l) may allow better identification of aseptic cases. Conclusion. The evaluated serum inflammatory markers showed limited diagnostic value in the preoperative diagnosis of FRI when using the uniform FRI Consensus Definition. Therefore, they should remain as suggestive criteria in diagnosing FRI. Although CRP showed a higher performance in comparison to the other serum markers, it is insufficiently accurate to diagnose a septic nonunion, especially when caused by low virulence microorganisms. Cite this article: Bone Joint J 2020;102-B(7):904–911

Aim. The aim was to investigate the value of quantitative histological analysis in the diagnosis of fracture-related infection (FRI). Patients and Methods. The clinical features, microbiology culture results and histological analysis in 156 surgically treated non-unions were used to stratify the likelihood of associated infection. There were 64 confirmed infected non-unions (≥1 confirmatory criteria; pus, sinus and bacterial growth in ≥2 samples), 66 aseptic non-unions (no confirmatory criteria) and 26 possibly infected (pathogen identified from a single specimen and no confirmatory criteria). The histological inflammatory response was assessed by average neutrophil polymorphs (NPs) counts per high power field (HPF) and compared to the established diagnosis. Results. Assuming a cut-off of >5NPs/HPF for positive histological diagnosis, there was 80% sensitivity and 100% specificity (accuracy 90%). Using a cut-off of any NPs/HPF (>0) for negative histological diagnosis there was a sensitivity of 98% and a specificity of 85% (accuracy 92%). Conclusion. Histology can be used in a bimodal fashion as a diagnostic test for FRI. The presence of >5 NPs/HPF has a positive predictive value of 100%, while the complete absence of any NPs is almost always indicative of an aseptic non-union (negative predictive value: 98%)

Aims

Monocyte-lymphocyte ratio (MLR) or neutrophil-lymphocyte ratio (NLR) are useful for diagnosing periprosthetic joint infection (PJI), but their diagnostic values are unclear for screening fixation-related infection (FRI) in patients for whom conversion total hip arthroplasty (THA) is planned after failed internal fixation for femoral neck fracture.

INTRODUCTION. The TFCC injuries are usually diagnosed by a coronal MRI. We have described the Float image for the diagnosis of peripheral injuries of the TFCC. In a sagital image parallel to the ulnar diaphysis and placed lateral to the ulnar fovea, we can observe the radiocubital dorsal and volar ligaments of the TFCC. A distance of more than 4mm between the dorsal edge of the meniscus and the joint capsule suggests the presence of TFCC peripheral rupture. METHOD. 51 pacients were selected from all the patients who underwent wrist arthroscopy between 2006–2009. Inclusion criteria: MRI at our hospital, arthroscopy at our hospital, no presence of radial fracture. We assessed the correlation between the presence of the Float image and a TFCC injury confirmed by arthroscopy. RESULTS. The Float image for the diagnosis of peripheral TFCC injuries has a sensibility of 0.929 [0.774 to 0.98] and a specificity of 0,857 [0.654 to 0.95]. PPV: 0.897 [0.736 to 0.964] and NPV: 0.9 [0.699 to 0.972]. CONCLUSIONS. The Float MRI is a high sensibility and specificity method for the diagnosis of peripheral TFCC. The coronal MRI is useful for diagnosing central ruptures but has less sensibility for the peripheral injuries

The aim of our study was to compare the clinical versus radiological diagnosis of patients suffering from a Morton's neuroma. Clinical assessments and pre operative radiological imaging of patients who underwent operative procedures for an excision of a Morton's neuroma were retrospectively compared. This review included 43 excised Morton's neuromas from 36 different patients over a period of 68 months, performed by one surgical team. The commonest clinical symptoms were those of pain or tingling on the plantar aspect of the affected webspace on direct palpation (100%), pain of weight bearing (91%) which was relieved by rest (81%) and pain on stretching the toes (79%). The most sensitive clinical sign was a Mulder's click. Our results showed that clinical assessment was the most sensitive method of diagnosing these neuromas (98%). All of our patients had at least one mode of radiological investigation. Ultrasonography was the commonest requested single imaging modality in our series. It was found to have a sensitivity of 90% (28/31). This imaging technique has the disadvantage of being operator dependant, as highlighted by the fact that one of our patients had a correct radiological diagnosis after a repeat ultrasound to the affected area was requested. Magnetic Resonance Image scan is a more expensive technique as it has the advantage of producing static reproducible images. As a single imaging modality, it was found to have a sensitivity of 92% (12/13) in our series. 3 patients had both imaging modalities; initial ultrasound failed to convincingly diagnose a neuroma in 2 cases and in the other case, the initial MRI did not show any pathology. In all these cases, the repeat imaging techniques confirmed the clinical diagnosis. We conclude that there is no absolute requirement for ultrasonography or magnetic resonance imaging in patients who clinically are suspected to have a Morton's neuroma, as the clinical examination was found to be the most sensitive method of diagnosis. We suggest that the two main indications for performing some form of imaging is (a) an unclear clinical assessment and (b) cases when more than one webspace appears to be affected. An ultrasound of the webspaces should be the radiological investigation of choice, followed by a magnetic resonance scanning if any uncertainty still remains

INTRODUCTION. A detailed clinical examination and investigations are required to evaluate the cause of persisting groin pain following a metal on metal (MoM) hip replacement. Adverse reaction to metallic debris (ARMD) is an emerging problem with MoM hip replacements. It is an umbrella term encompassing metallosis, pseudo-tumors and aseptic lymphocytic vasculitis associated lesions (ALVAL). The role of imaging in the diagnosis of this complex problem is still unclear. A study was undertaken to evaluate the efficacy of ultrasound in diagnosis of ARMD following a MoM hip replacement. METHODS. The study group included 35 patients with a clinical and histological diagnosis of ARMD, who had a preoperative ultrasound. All ultrasound procedures were performed on the anterior and lateral aspects of the painful hip with a high frequency probe of 9–13 MHz (Sonoline Antares – Siemens). RESULTS. All patients diagnosed with ARMD had abnormalities identified on ultrasound. Fluid inside the joint was noted in 30 out of 35 procedures (85.7 %). Fluid outside the joint was noted in 33 procedures (94.3 %). Amongst the patients with fluid outside the joint, 32 had iliopsoas and 30 had trochanteric bursitis. Echogenic reflections were noted in 31 out of 35 procedures (88.6 %). Considerable attenuation or absence of iliopsoas and gluteus tendon reflection was seen in many patients with echogenic fluid collections on the anterior and trochanteric aspects of hip. Progression of such changes was noted on further 5 patients, who had a repeat ultrasound within an interval of 3–6 months. 1 patient had a progression from anechogenic to echogenic joint effusion. DISCUSSION. Different radiological investigations including MRI scan have been used for evaluation of painful MoM hip arthroplasty. To our knowledge, this is the first study to demonstrate the efficacy of ultrasound in diagnosis of ARMD. Floating echogenic reflections and fluid collections around iliopsoas and gluteus medius/minimus tendons is highly suggestive of ARMD. Ultrasound is a cheap, non-invasive and dynamic investigation and has been shown to be reliable in diagnosis of ARMD

Introduction. Microbiological diagnosis of bone and joint infections (BJIs) currently relies on standard cultures which are time consuming and lack sensitivity. Various molecular approaches have been described and allowed improvement of BJI diagnosis. This study evaluated for the first time the performance of a DNA microarray-based assay (Prove-it™ Sepsis assay, PISA) for the rapid (<6 hours) detection and identification of 50 different species involved in BJI directly from clinical samples. Material and methods. We retrospectively selected 130 bone and joint samples (67 synovial fluids and 63 bone biopsies) including 114 positive and 16 negative samples. The microbiological diagnosis had been previously established either by culture(C+, n=53) or by PCR16S and sequencing when culture was negative (C-/PCR+). The positive samples were selected to match the species targeted on the DNA microarray. DNA extraction was performed before proceeding to PISA amplification and hybridization on every selected sample. Results. Among the 16 negative samples, one was detected positive with S. epidermidis by PISA, result that was secondarily confirmed using specific PCR. Among the 114 positive samples, 62.3% were positive using PISA with highly concordant identification compared to culture and PCR16S/sequencing results. Forty-three samples (37.7%) remained negative, illustrating a defect of sensitivity. However, PISA accurately detected methicillin resistance not only among the 16 C+/PISA+ Staphylococcus species (n=5) but also among the 28 C-/PCR16S+ Staphylococcus species (n=12) offering crucial rapid information to adapt the treatment of staphylococcal BJIs. Seven polymicrobial samples were also identified without extensive experiments. Discussion – Conclusion. Even if the sensitivity deserves to be improved by optimizing DNA extraction and investigating on human DNA interference, these preliminary promising results highlight that this new and simple microarray method could be in the future an alternative to conventional PCR16S for the diagnosis of BJI

Objectives. Establishing the diagnosis of implant-associated infections is often difficult, because of variable clinical presentations and lack of uniform diagnostic criteria. Sonication of removed orthopedic devices was shown to have superior sensitivity and specificity for infection. We evaluated the value of microcalorimetry as a quick and reliable tool in the diagnosis of infection in sonication fluid from removed implants. Methods. Between 10/2009 and 02/2010 we prospectively included all removed orthopaedic devices at our institution, which were subjected to sonication. Periprosthetic tissue cultures were performed as standard procedure. The removed device was sonicated in Ringer solution (40 kHz, 1 minute) and the resulting fluid was cultured and centrifuged (3000 × g, 10 minutes). The resulting pellet was resuspended in 3 ml tryptic soy broth for isothermal microcalorimetry (sensitivity of 0.25 μW). The detection time until increase of 20 μW was calculated. A 48-channel batch calorimeter (TA Instruments, New Castle, DE, USA) was used to measure the heat flow at 37°C controlled at 0.0001 °C. Results. 39 cases were included (24 males, mean age ± SD was 63 ± 16 years). 29 cases were orthopedic prostheses (14 hip, 11 knee, 1 shoulder and 1 joint spacers) and 10 cases osteosynthetic materials (6 screws, 3 plates, 1 cement-nail). 13 cases (33%) were infected, of which 10 (77%) were positive in sonication culture and 12 (92%) in microcalorimetry. The mean detection time by microcalorimetry was 11.4 h (range, 0.2 h–20.9 h). Examples for microcalorimetric signals can be seen in Fig.1. Conclusions. Microcalorimety of sonication fluid showed superior sensitivity for the diagnosis of infection with detection time of <24 h. This method is a promising diagnostic assay for a rapid and accurate diagnosis of infections associated with orthopedic devices

Aims

Malreduction of the syndesmosis has been reported in up to 52% of patients after fixation of ankle fractures. Multiple radiological parameters are used to define malreduction; there has been limited investigation of the accuracy of these measurements in differentiating malreduction from inherent anatomical asymmetry. The purpose of this study was to identify the prevalence of positive malreduction standards within the syndesmosis of native, uninjured ankles.

The Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score was developed in 2004 to risk-stratify patients with soft tissue infections using common blood tests when the clinical picture is equivocal. A score ≥ 6 conferred a positive predictive value (PPV) of 92% and negative predictive value of 96% for necrotising fasciitis.

We retrospectively calculated LRINEC scores for Orthopaedic patients admitted to ITU in our hospital with limb soft-tissue infection and confirmed Group-A Streptococcus or Staphylococcus in fluid, blood, tissue or swab culture between 2010–2017 (n=10). Mean age = 57.4 and 60% were female. Half of all patients died during admission. Mean LRINEC score of all patients was 5.3±3.1 (median = 6). Mean score in deceased patients was 4.8±2.8 (scores: 0,5,6,6,7; median = 6); in discharged patients mean = 5.8±3.7 (scores: 0,5,7,7,10; median = 7). 6 patients had a score ≥6, making our PPV 60%. 4 patients had necrotising fasciitis confirmed on histology (LRINEC scores = 0,5,7,10).

Our PPV of 60% is less than the figure obtained in the original paper. 2 patients with a LRINEC score <6 died during admission, including a patient with a score of 0. Furthermore, a patient with necrotising fasciitis confirmed on histology also had a LRINEC score of 0. We conclude that LRINEC scores should not delay surgery when clinical suspicion is high, and should be used as an adjunct to clinical decision-making, rather than a replacement, as patients with low LRINEC scores can also have confirmed necrotising fasciitis and poor outcomes.

Septic Arthritis is an important life threatening condition affecting all age groups with a mortality of up to 11%. Our aim was to perform a study of the demographics, length of stay, complications and investigate if time delay of surgical treatment from the time of diagnosis has an impact on mortality and morbidity of the patients. Methods. We performed a retrospective study of all the patients presented to our Hospital between 2005 and 2009 with septic arthritis who underwent arthroscopic lavage as definitive intervention. We excluded the patients involving minor joints. Data collection was performed from case notes, microbiology and haematology laboratory results. We divided the patients into three groups based on the time from diagnosis to arthroscopic lavage as T1 (less than 12 hours), T2 (12–24 hours) and T3 (more than 24 hours). Our primary outcome measures were mortality and complications such as Intensive Care Admission. Secondary outcome measures included average length of stay in each group. Results. A total of 57 patients were evaluated. The average age of the patients was 49.7 (10 months–94 years). 2 patients of T1 group died (5.4%) 3 patients of T1 group needed Intensive Care Unit (ICU) management (8.1%). There were no deaths or ICU admissions in the other groups. 40.3% of patients needed arthroscopic lavage more than once. The average length of stay of T1 was 19.8 days, T2–11.5 days and T3–27.5 days. Majority of the joints involved were knees (63.1%).23 patients (40.3%) had a preceding intervention performed in the same joint. Staphyloccus aureus was the most common organism isolated in 14 patients (26.3%). Conclusion. There was insufficient evidence to show a significant correlation between the time lag and mortality associated with septic arthritis. However, further large scale retrospective multicenter based studies would be beneficial in identifying the factors associated with complications of septic arthritis. Our study demonstrates high morbidity and mortality rates in T1 group which may be biased due to highly unstable patients in this group in comparision to the other two groups

There is much debate regarding the use of continuous-compartment-pressure-monitoring (CCM) in the diagnosis of acute compartment syndrome (ACS). We retrospectively reviewed the management of all patients (aged 15 and over) who were admitted with a fracture of the tibial diaphysis, across 3 centres, during 2013–2015. Patient demographics, pre-existing medical problems, initial treatment, subsequent complications, methods of compartment monitoring, and follow-up were all included in the data collection. We separated patients into monitored (MG) and non-monitored groups (NMG), and compared the outcomes of their treatment. Data analysis was performed using SPSS and statistical significance was set as p < 0.05. 287 patients were included in this study (116 NMG vs. 171 MG). There were no significant differences observed in age, sex, previous medical problems, length of stay, AO classification of fracture and post-operative complications between the groups. 21 patients were suspected to have developed ACS (n=8 NMG 6.9percnt;, n=13 MG 7.6percnt;) and were treated with acute decompression fasciotomies. The average time from admission to fasciotomy was 20.3 hours (21.25hrs NMG, 19.5hrs MG p=0.448). There was no significant difference in the average length of hospital stay and documentation of complications at follow up between the 2 groups. There were no reported cases of soft tissue infections associated with the use of CCM. This study illustrates that CCM does not increase the rate of fasciotomies in this patient group, or reduce the time to fasciotomy significantly. There was no evidence to suggest that use of CCM is associated with superficial or deep infection

Introduction. Rapid identification of bacteria from extemporaneous samples would greatly help management of prosthesis joint infection. The aim of the present retrospective study was to evaluate a new molecular assay (GeneXpert MRSA-SA SSTI (Cepheid)) for detecting Staphylococcus aureus (SA) and methicillin resistance directly from bone and joint samples in less an hour (58 minutes). Material et method. Retrospective study using 91 frozen samples (76 patients) of joints (n=24), bone biopsies (n=42) and tissue biopsies (n=25):. -. SA positive samples: n=72 (methicillin susceptible SA (MSSA), n=63; methicillin resistant MRSA, n=9). -. SA positive samples: n=19. The results were compared with routine results (culture in solid and liquid medium, identification and susceptibility test) from each participating lab. Results. The 72 SA positive samples gave:. -. 68 concordant positive results comprising:. . 9 MRSA positive samples,. . 56 MSSA positive samples,. . 3 MSSA positive samples, positive for SA but with inconclusive results for methicillin resistance. -. 4 negative discordant results for MSSA positive samples. The 19 SA negative samples gave:. . 16 concordant negative results. . 3 SASM positive results for negative culture of samples obtained from patients with other MSSA positive deep or superficial samples, suggesting a higher sensitivity for the GeneXpert test than culture in these cases. Sensitivity and specificty for bone and joint samples:. Se=68/72=94.4%. Sp=16/16=100%. Conclusion. The GeneXpert MRSA-SA SSTI assay provides 58-minute detection of MSSA and MRSA directly from bone and joint samples. Sensitivity and specificity were excellent in this preliminary study. This test may enable real-time peroperative diagnosis of Staphylococcus aureus, which could be very useful in the field of revision surgery. Further prospective studies should be done to accurately determine the PPV, NPV, and clinical and pharmaco-economic impact of this test in the setting of prosthesis joint infection

Incomplete intertrochanteric fractures do not extend across to the medial femoral cortex and are stable, without rotational deformity or shortening of the lower limb. The aim of our study was to establish whether they can be successfully managed conservatively. A total of 68 patients over a five-year period presented with a suspected fracture of the femoral neck and underwent an MRI scan for further assessment. From these, we retrospectively reviewed eight patients with normal plain radiographs but with an incomplete, intertrochanteric fracture on MRI scan. Five were managed conservatively and three operatively.

The mean length of hospital stay was 16 days for the conservatively-treated group and 15 days for those who underwent surgery; this was not statistically significant (p > 0.5) and all patients were mobilised on discharge. Although five patients were readmitted at a mean of 3.2 years after discharge, none had progressed to a complete fracture. We believe that patients with incomplete intertrochanteric fractures should be considered for conservative treatment.

Most fractures of the radial head are stable undisplaced or minimally displaced partial fractures without an associated fracture of the elbow or forearm or ligament injury, where stiffness following non-operative management is the primary concern. Displaced unstable fractures of the radial head are usually associated with other fractures or ligament injuries, and restoration of radiocapitellar contact by reconstruction or prosthetic replacement of the fractured head is necessary to prevent subluxation or dislocation of the elbow and forearm. In fractures with three or fewer fragments (two articular fragments and the neck) and little or no metaphyseal comminution, open reduction and internal fixation may give good results. However, fragmented unstable fractures of the radial head are prone to early failure of fixation and nonunion when fixed. Excision of the radial head is associated with good long-term results, but in patients with instability of the elbow or forearm, prosthetic replacement is preferred.

This review considers the characteristics of stable and unstable fractures of the radial head, as well as discussing the debatable aspects of management, in light of the current best evidence.

Cite this article: Bone Joint J 2013;95-B:151–9.

Failure to treat acute compartment syndrome (ACS) early leads to significant morbidity. Current practice depends on using clinical signs and intracompartmental pressure (ICP) monitoring to diagnose the syndrome but there is still debate regarding their accuracy and interpretation.

Patients admitted with injuries at risk of ACS underwent intramuscular (IM) pH and ICP monitoring combined with regular clinical assessment. Fasciotomies were performed on those with clinical and/or pressure based evidence of ACS. All patients were subsequently assessed for evidence of a missed ACS at at 6 & 12 months.

Of the 62 patients, 51 completed the protocol and were included in the analysis. They were divided into 2 groups: those who had ACS, either initially (fasciotomies; 13), or diagnosed at follow up (no fasciotomies; 7), and those with no evidence of ACS (31).

The sensitivity and specificity for the worst values for each variable were calculated and receiver operator characteristic (ROC) curves generated. The area under the curve for pH was 0.92, 0.73 for absolute pressure and 0.59 for delta pressure. To achieve a sensitivity of 95%, an absolute pressure of >30mmHg was 30% specific, a delta pressure of <33mmHg was 27%, while IM pH of 6.38 was 80% specific.

This study highlights the issues concerning current diagnostic methods for ACS. By comparison, IM pH radically out performed both the highest ICP and the lowest delta pressure, identifying patients early and accurately.

We studied the merits of physical examination after inversion injury of the ankle in 160 consecutive patients. They had an explanatory operation if they had a positive arthrogram and/or positive signs on a delayed physical examination.

To determine the interobserver variation in delayed physical examination, five different examiners were asked to give independent assessment of the injury. Those with limited clinical experience produced more accurate results when physical examination was performed at five days after the injury, rather than within 48 hours.

The specificity and sensitivity of delayed physical examination for the presence or absence of a lesion of an ankle ligament were found to be 84% and 96%, respectively. The interobserver agreement for the delayed physical examination of the ankle was good (kappa values 0.5, 0.6, 0.6 and 1.0).

Delayed physical examination gives information of diagnostic quality which is equal to that of arthrography, and causes little discomfort to the patient.

Aims. This study aimed to describe practice variation in the use of total hip arthroplasty (THA) for older patients with femoral neck fracture and to determine the association between patient, surgeon, and institution factors and treatment with THA. Methods. We performed a cross-sectional analysis of 49,597 patients aged 60 years and older from Ontario, Canada, who underwent hemiarthroplasty or THA for femoral neck fracture between 2002 and 2017. This population-based study used routinely collected healthcare databases linked through ICES (formerly known as the Institute for Clinical Evaluative Sciences). Multilevel logistic regression modelling was used to quantify the association between patient, surgeon, and institution-level variables and whether patients were treated with THA. Variance partition coefficient and median odds ratios were used to estimate the variation attributable to higher-level variables and the magnitude of effect of higher-level variables, respectively. Results. Over the study period, 9.4% of patients (n = 4,638) were treated with THA. Patient factors associated with higher likelihood of treatment by THA included: younger age, male sex, and diagnosis with rheumatoid arthritis. Long-term care residence, use of home care services prior to hip fracture, diagnosis of dementia, higher comorbidity burden, and the most marginalized group were negatively associated with treatment by THA. Treating surgeon and institution accounted for 54.2% and 17.8% of the total variation in treatment with THA, respectively. Surgeon volume of THA procedures in the 365 days prior to surgery was the strongest higher-level predictor of treatment with THA. Specific treating surgeons and institutions still accounted for significant proportions of the variability in treatment with THA (40.3% and 19.5% of total observed variation, respectively) after controlling for available patient, surgeon, and institution-level variables. Conclusion. The strongest predictors for treatment of patients with femoral neck fracture with THA were patient age, treating surgeon, and treating institution. This practice variation highlights differential access to care for patients. Cite this article: Bone Joint J 2023;105-B(2):180–189

Introduction. The knee is the most commonly injured joint in sporting accidents, leading to substantial disability, time off work and morbidity (1). Treatment and assessment vary around the UK (2), whilst there remains a limited number of high-quality randomised controlled trials assessing first time, acute soft tissue knee injuries (3,4). As the clinical and financial burden rises (5), vital answers are required to improve prevention, diagnosis, treatment, rehabilitation, and delivery of care. In association with the James Lind Alliance, this BASK, BOSTAA and BOA supported prioritising exercise was undertaken over a year. Methods. The James Lind Alliance methodology was followed; a modified nominal group technique was used in the final workshop. An initial survey invited patients and healthcare professionals to submit their uncertainties regarding soft tissue knee injury prevention, diagnosis, treatment, rehabilitation, and delivery of care. Seventy-four questions were formulated to encompass common concerns. These were checked against best available evidence. Following the interim survey, 27 questions were taken forward to the final workshop in January 2023, where they were discussed, ranked, and scored in multiple rounds of prioritisation by groups of healthcare professionals, patients, and carers. Results. Over 1000 questions were submitted initially. Twenty-seven were taken forward to the final workshop following the surveys. Nearly half of the responses were from patients/carers. The Top 10 (Figure 1) includes prevention, diagnosis, treatment, and rehabilitation questions, reflecting the concerns of patients, carers, and a wider multidisciplinary team. Conclusion. This validated process has generated an important, wide- ranging Top 10 priorities for future soft tissue knee injury research. These have been submitted to the National Institute for Health and Care Research and are now available for researchers to investigate. The final 27 questions which were taken to the final workshop have also been published on the James Lind Alliance website. Research into these questions will lead to future high-quality research, thus improving patient care & outcomes. For any figures or tables, please contact authors directly