There have been no studies assessing the acceptability of opioid tapering in the pre-arthroplasty setting. This qualitative study aimed to (1) explore barriers and facilitators to opioid tapering amongst patients with chronic non-cancer pain (CNCP), and (2) explore the similarities and differences in acceptability of opioid tapering between pre-arthroplasty patients and those participating in a biopsychosocial pain management program.

From January 2021, adult participants diagnosed with CNCP and taking opioids daily (any dose at time of screening for a period of 3 months) were recruited from either Fairfield Orthopaedic Hip and Knee Service (FOHKS) or Liverpool Hospital Pain Clinic (LHPC). Semi-structured interviews underwent thematic analysis using the framework method.

17 participants were recruited (FOHKS, n=9, mean age 67, female 77%, LHPC, n=8, mean age 54, female 63%). Both groups had participants who; (i) were reluctant to use opioid medications and used them out of “necessity”, (ii) were reluctant to taper due to concerns of worsening pain, quality of life, (iii) believed opioids were “toxins” causing bodily harm. Some FOHKS participants believed tapering should be a post-operative focus, whilst others believed tapering opioids pre-operatively will assist in post-op pain management. Few LHPC participants felt dependent/addicted to opioids, thus driving their intention to taper opioids.

The belief of tapering opioids causing worse pain was based on either previous experiences or concerns alone. Some FOHKS participants were more inclined to taper opioids if they were educated on the chronic and peri-operative risks associated with using opioids at time of arthroplasty.

Opioid users recognise the harms associated with chronic opioid use and believe they are used out of desperation for adequate analgesia, function, and quality of life. Tapering opioids in the pre-arthroplasty context may need coupling with patient education highlighting the importance of opioid tapering pre-operatively.

Aim. Periprosthetic Joint Infection (PJI) is a devastating complication in hip and knee joint arthroplasty. The “JS BACH” classification system was developed in 2021 to stratify the complexity of PJI, and more importantly, to act as a tool to guide referrals to specialist centers. The “JS BACH” classification has not been validated in an external cohort. This study aimed to do so using a large prospective cohort from Australia and New Zealand. Method. We applied the JS-BACH classification to the Prosthetic Joint Infection in Australia and New Zealand Observational (PIANO) cohort. This prospective study of newly diagnosed PJI collected 2-year outcome data from 653 participants enrolled in 27 hospitals. The definition of PJI treatment failure at 24 months was any of the following: death, clinical or microbiological signs of infection, destination prosthesis removed, or ongoing antibiotic use. Results. Individual cases were classified as per JS-BACH into “1 - uncomplicated” (n = 268), “2 - complex” (n = 330), and “3 - limited options” (n = 55). This cohort was similar to the original JS-BACH population in terms of baseline characteristics. However, there was a difference in complexity, with more DAIR procedures, fewer revision procedures, and a higher proportion of uncomplicated patients in the PIANO cohort. The risk of treatment failure correlated strongly with the JS-BACH category, with odds ratios (95% CI [confidence interval]) for category 2 versus 1 of 1.75 (1.24 to 2.47) and for category 3 versus 1 of 7.12 (3.42 to 16.02). Conclusions. Despite the PIANO study population being less complicated than the original derivation cohort, the JS-BACH classification showed a clear association with treatment failure in this large external cohort

Aims

Slipped capital femoral epiphysis (SCFE) is one of the most common hip diseases of adolescence that can cause marked disability, yet there is little robust evidence to guide treatment. Fundamental aspects of the disease, such as frequency, are unknown and consequently the desire of clinicians to undertake robust intervention studies is somewhat prohibited by a lack of fundamental knowledge.

Abstract. Objective. Meta-analysis of clinical trials highlights that non-operative management of degenerative knee meniscal tears is as effective as surgical management. Surgical guidelines though support arthroscopic partial meniscectomy which remains common in NHS practice. Physiotherapists are playing an increasing role in triage of such patients though it is unclear how this influences clinical management and patient outcomes. Methods. A 1-year cohort (July 2019–June 2020) of patients presenting with MRI confirmed degenerative meniscal tears to a regional orthopaedic referral centre (3× ESP physiotherapists) was identified. Initial clinical management was obtained from medical records alongside subsequent secondary care management and routinely collected outcome scores in the following 2-years. Management options included referral for surgery, conservative (steroid injection and rehabilitation), and no active treatment. Outcome scores collected at 1- and 2-years included the Forgotten Joint Score-12 (FJS-12) questionnaire and 0–10 numerical rating scales for worst and average pain. Treatment allocation is presented as absolute and proportional figures. Change in outcomes across the cohort was evaluated with repeated measures ANOVA, with Bonferroni correction for multiple testing, and post-hoc Tukey pair-wise comparisons. As treatment decision is discrete, no direct contrast is made between outcomes of differing interventions but additional explorative outcome change over time evaluated by group. Significance was accepted at p=0.05 and effect size as per Cohen's values. Results. 81 patients, 50 (61.7%) male, mean age 46.5 years (SD13.13) presented in the study timeframe. 32 (40.3%) received conservative management and 49 (59.7%) were listed for surgery. Six (18.8%) of the 32 underwent subsequent surgery and nine of the 49 (18.4%) patients switched from planned surgery to receiving non-operative care. Two post-operative complications were noted, one cerebrovascular accident and one deep vein thrombosis. The cohort improved over the course of 2-years in all outcome measures with improved mean FJS-12 (34.36 points), mean worst pain (3.74 points) average pain (2.42 points) scores. Overall change (all patients) was statistically significant for all outcomes (p<0.001), with sequential year-on-year change also significant (p<0.001). Effect size of these changes were large with all Cohen-d values over 1. Controlling for age and BMI, males reported superior change in FJS-12 (p=0.04) but worse pain outcomes (p<0.03). Further explorative analysis highlighted positive outcomes across all surgical, conservative and no active treatment groups (p<0.05). The 15 (18%) patients that switched between surgical and non-surgical management also reported positive outcome scores (p<0.05). Conclusion(s). In a regional specialist physiotherapy-led soft tissue knee clinic around 60% of degenerative meniscal tears assessed were referred for surgery. Over 2-years, surgical, non-operative and no treatment management approaches in this cohort all resulted in clinical improvement suggesting that no single strategy is effective in directly treating the meniscal pathology, and that perhaps none do. Clinical intervention rather is directed at individual symptom management based on clinical preferences. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Abstract. Introduction. Total knee replacement (TKR) is a successful operation for many patients, however 15–20% of patients experience chronic post-surgical pain (CPSP). Many will experience neuropathic characteristics. We describe the prevalence and patterns of neuropathic pain in a cohort of patients with CPSP three months after TKR. Methodology. Between 2016–2019, 363 patients with troublesome pain, ≤14 on Oxford Knee score pain subscale, at three months after TKR from eight NHS hospitals were recruited into the Support and Treatment After Replacement (STAR) trial. Self-reported neuropathic pain was assessed at three, nine and fifteen months after surgery using painDETECT and Douleur Neuropathique 4 (DN4). Results. At three months post-operative, 53% reported neuropathic pain on painDETECT and 74% on DN4. Half (56%) remained in neuropathic pain over the twelve-month follow-up period, 26% reported improvement, and 9% reported new neuropathic symtpoms or fluctuated in and out of neuropathic pain (9%). Overall mean neuropathic pain scores improved between three and 15 months after TKR. When the painDETECT cut-off score of ≥13(ambiguous/possible) was used, DN4 and painDETECT measures showed similar prevalence rates at each timepoint. Conclusion. Neuropathic pain is common among patients with CPSP at three months after TKR. Although symptoms improved over time, one quarter to one half of our cohort continued to report symptoms at fifteen months. We propose a painDETECT cutoff score of ≥13 be used to identify neuropathic features in the TKR population. Postoperative care should include identification, assessment, and treatment of neuropathic pain in patients with CPSP after TKR

Aims. Large-diameter metal-on-metal (MoM) total hip arthroplasty (THA) has demonstrated unexpected high failure rates and pseudotumour formation. The purpose of this prospective cohort study is to report ten-year results in order to establish revision rate, prevalence of pseudotumour formation, and relation with whole blood cobalt levels. Methods. All patients were recalled according to the guidelines of the Dutch Orthopaedic Association. They underwent clinical and radiographical assessments (radiograph and CT scan) of the hip prosthesis and whole blood cobalt ion measurements. Overall, 94 patients (95 hips) fulfilled our requirements for a minimum ten-year follow-up. Results. Mean follow-up was 10.9 years (10 to 12), with a cumulative survival rate of 82.4%. Reason for revision was predominantly pseudotumour formation (68%), apart from loosening, pain, infection, and osteolysis. The prevalence of pseudotumour formation around the prostheses was 41%, while our previous report of this cohort (with a mean follow-up of 3.6 years) revealed a 39% prevalence. The ten-year revision-free survival with pseudotumour was 66.7% and without pseudotumour 92.4% (p < 0.05). There was poor discriminatory ability for cobalt for pseudotumour formation. Conclusion. This prospective study reports a minimum ten-year follow-up of large-head MoM THA. Revision rates are high, with the main reason being the sequelae of pseudotumour formation, which were rarely observed after five years of implantation. Blood ion measurements show limited discriminatory capacity in diagnosing pseudotumour formation. Our results evidence that an early comprehensive follow-up strategy is essential for MoM THA to promptly identify and manage early complications and revise on time. After ten years follow-up, we do not recommend continuing routine CT scanning or whole cobalt blood measurements, but instead enrolling these patients in routine follow-up protocols for THA. Cite this article: Bone Jt Open 2022;3(1):61–67

Periprosthetic joint infections (PJIs) centers are garnering the attention of different arthroplasty surgeons and practices alike. Nonetheless, their value has yet to be proven. Therefore, we evaluated weather PJI centers produce comparable outcomes to the national average of THA PJIs on a national cohort. We performed a retrospective review of patient data available on PearlDiver from 2015 – 2021. PJI THA cases were identified through ICD-10 and CPT codes. Patients treated by 6 fellowship trained arthroplasty surgeons from a PJI center were matched based on age, gender, Charlson Comorbidity Index and Elixhauser comorbidity index at a 1:1 ratio to patients from the national cohort. Compared outcomes included LOS, ED visits, number of patients readmitted, total readmissions. Sample sized did not allow the evaluation of amputation, fusion or explantation. Normality was tested through the Kolmogorov-Smirnov test. And comparisons were made with Students t-tests and Chi Square testing. A total of 33,001 THA PJIs and were identified. A total of 77 patients were identified as treated by the PJI center cohort and successfully matched. No differences were noted in regard to age, gender distribution, CCI or ECI (p=1, 1, 1 and 0.9958 respectively). Significant differences were noted in mean LOS (p<0.43), number of patients requiring readmissions (p=0.001) and total number of readmission events (p<0.001). No difference was noted on ED visits. Our study demonstrates that a PJI for THA cases may be beneficial for the national growing trend of arthroplasty volume. Future data, that allows comparison of patient's specific data will allow for further validation of PJI centers and how these can play a role in helping the national PJI growing problem

Introduction. The ACTIVE(Advanced Cartilage Treatment with Injectable-hydrogel Validation of the Effect) study investigates safety and performance of a novel dextran-tyramine hydrogel implant for treatment of small cartilage defects in the knee (0.5-2.0cm2). The hydrogel is composed of a mixture of natural polymer conjugates that are mixed intra-operatively and which cross-link in situ through a mild enzymatic reaction, providing a cell-free scaffold for cartilage repair. Method. The ACTIVE study is split into a safety (n=10) and a performance cohort (n=36). The Knee Injury and Osteoarthritis Outcome Score (KOOS), pain (numeric rating scale, NRS), Short-Form Health Survey (SF-36) were compared at baseline and 3, 6, and 12 months after surgery. The primary performance hypothesis is an average change in the KOOS from baseline to 12 months (ΔKOOS) greater than a minimal clinically important change (MIC) of 10. No statistical tests were performed as these are preliminary data on a smaller portion of the total study. Result. All patients of the safety cohort (n=10, mean age±SD, 30±9 years) were treated with the hydrogel for a symptomatic (NRS≥4) cartilage defect on the femoral condyle or trochlear groove (mean size±SD, 1.2±0.4cm2). No signs of an adverse foreign tissue reaction or serious adverse events were recorded within the safety cohort. At final follow-up mean KOOS±SD was 66.9±23.5, mean NRS resting±SD was 1.3±1.9, NRS activity±SD was 3.8±2.9 and mean SF-36±SD was 72.0±10.9. ΔKOOS was 21. One patient sustained new knee trauma prior to final follow-up, affecting final scores considerably. When excluded, ΔKOOS was 24(n=9). Conclusion. These promising initial findings provide a solid basis for continuation and expansion of this unique cartilage treatment. The MIC of 10 was surpassed. Though, results should be interpreted cautiously as they are based solely on preliminary data of the first 10 patients. Acknowledgements. Study is sponsored by Hy2Care, producer of the CartRevive®(dextran-tyramine) Hydrogel implant

Aim. Culture negative (CN) prosthetic joint infections (PJI) account for approximately 10% of all PJIs and present significant challenges for clinicians. We aimed to explore the significance of CN PJI within a large prospective cohort study, and to compare their characteristics and outcomes with culture positive cases. Methods. The Prosthetic joint Infection in Australia and New Zealand Observational (PIANO) study is a prospective, binational, multicentre observational cohort study conducted at 27 hospitals between July 2014 and December 2017. We compared baseline characteristics and outcomes of all patients with culture negative (CN) prosthetic joint infection (PJI) from the PIANO cohort with culture positive (CP) cases. “Treatment success” was defined as absence of clinical or microbiological signs of infection, no need for ongoing antibiotics, and no need for revision or resection arthroplasty since the end of the initial treatment. We also describe PJI diagnostic criteria in the CN cohort and apply internationally recognised PJI diagnostic guidelines. Results. Of the 650 patients eligible for inclusion, 55 (8.5%) were CN and 595 were CP. Compared with the CP cohort, CN patients were more likely to be female [32 (58.2%) vs 245 (41.2%); p=0.02], involve the shoulder joint [5 (9.1%) vs. 16 (2.7%); p=0.03] and have a lower mean C-reactive protein (142 mg/L vs. 187 mg/L; p=0.02). Overall, outcomes were superior in CN patients, with culture negativity an independent predictor of treatment success at 24 months (aOR 3.78; 95%CI 1.65 – 8.67). Of the 55 CN cases meeting Infectious Diseases Society of America (IDSA) diagnostic criteria, 45 (82%) met European Bone and Joint Infection Society (EBJIS) criteria (probable or definite) and 39 (71%) met the 2013 Musculoskeletal Infection Society (MSIS) criteria. Conclusions. Culture negativity is an independent predictor of treatment success in PJI. It is unclear whether this is because some of them are not actually infections, or for other reasons such as lower bacterial load or earlier effective antibiotic treatment. Diagnostic criteria for PJI vary substantially in their sensitivity, with MSIS criteria being the least sensitive. Acknowledgements. This work is being presented on behalf of the broader PIANO investigators and the Australasian Society for Infectious Diseases Clinical Research Network. The PIANO study received seed funding from Heraeus Medical and the John Hunter Hospital Charitable Trust Fund

We present a consecutive case cohort of the first 100 Birmingham Hip Resurfacing (BHR)'s in 90 patients with a minimum follow up of 20 years. All procedures were performed by a single surgeon having commenced the study in 1998. The original cohort included 68 males with 75 hips (7 bilateral) and 22 females with 25 hips (3 bilateral). The mean age at index procedure was 52. Patients were recalled to review in clinic as per Medicines and Healthcare products Regulatory Agency guidelines with x-rays, metal ions and Harris Hip Scores recorded. After a minimum of 20 year follow-up review the known overall revision rate is 11%. 11 have died and 7 have been lost to review. In males the known revision rate is 4/75 (5%), 3 of which were due to early fractures and 1 revision for infection at 5 years. The known revision rate in females is 7/25 (28%) of which 6 were due to adverse reactions to metal debris; 3 at 7–8 yrs, 1 at 15 yrs, 2 at 18 years, and 1 at 2 months for avascular necrosis. The mean 20 year metal ions results were cobalt 36.6 nmol/l (range 7.4–232.1) and chromium 32.1 nmol/l (range 6–120.8). The mean Harris hip score was 88.5 (range 38.6–99.8). This case series with 20 years follow-up demonstrates excellent long term survival of the BHRs further to registry BHR data and similar to THR for same age recipients. Applying today's strict criteria for patient selection would likely improve survival rate further. BHR has not demonstrated the catastrophic revision rates associated with some metal-on-metal resurfacing and remains a safe option for those who meet the criteria

Most hip replacements are performed in an in-patient setting; however, there has been a shift in recent years in Canada towards doing more on an outpatient basis. In 2021–2022, 15.6% of hip replacements were performed as day surgeries compared to 0.7% in 2018–2019. This analysis will assess patient reported outcome measures of patients who had inpatient versus outpatient hip replacement surgery between 2018 and 2021. We analysed a retrospective sample of 4917 adult patients who had an elective primary unilateral hip replacement. Preoperative and three-month postoperative PROMs were completed - the Oxford Hip Score, EQD5L and patient satisfaction with the outcome were recorded. Patients who had an outpatient procedure were matched 1:1 with patients who are admitted to hospital for surgery based on age, sex and pre-COVID versus the COVID (March 15, 2020 as the start). Preoperative PROMs and Charlson Comorbidity Index were collected. T-tests and chi-square tests were used to assess the differences. The inpatient group on average was older, female and had a lower preoperative PROMs score and more comorbidities than the outpatient group. With cohort matching the sample consisted of 1244 patients. The inpatient and outpatient groups have similar Oxford scores, postoperative EQ-5D-5L scores and the proportion satisfied with their surgical results. The Oxford postoperative score was slightly higher in the outpatient group compared to the inpatient group; however, this is not clinically significant. We observed that outpatient protocols have no difference in patient satisfaction, self-reported functional outcomes and self-reported health-related quality of life three months after a hip replacement. Day surgery protocols represented potential solution to the challenges caused by the expected increase in demand for hip replacements. Our results demonstrated that patients do well clinically with day surgery procedures and there does not appear to be any detrimental effect on PROMs

Introduction. Temporary spanning fixation aims to provide bony stability whilst allowing access and resuscitation of traumatised soft-tissues. Conventional monolateral fixators are prone to half-pin morbidity in feet, variation in construct stability and limited weight-bearing potential. This study compares traditional delta-frame fixators to a circular trauma frame; a virtual tibial ring block spanned onto a fine-wire foot ring fixation. Materials and Methods. The two cohorts were compared for demographics and fracture patterns. The quality of initial reduction and the maintenance of reduction until definitive surgery was assessed by two authors and categorised into four domains. Secondary measures included fixator costs, time to definitive surgery and complications. Results. Fifty-six delta-frames and 48 circular fixators were statistically matched for demographics and fracture pattern. Good or excellent initial reduction was achieved in 51 (91%) delta-frames and 48 (100%) circular fixators (p=0.022). Loss of reduction was observed in 15 (27%) delta-frames and 3 (6%) circular fixators (p<0.001). Post-fixator dislocation occurred in five (9%) delta-frames and one (2%) circular fixator (p=0.147). Duration in spanned fixation was equivalent (11.5 and 11.6 days respectively, p=0.211). Three (5%) delta-frames and 12 (25%) circular fixators were used as definitive fixation. The mean hardware cost was £3,116 for delta-frames and £2,712 for circular fixators. Conclusions. Temporary circular fixation offers statistically superior intra-operative reduction and maintenance of reduction, facilitates weight-bearing and provides more opportunity as the definitive fixation. Circular fixation hardware proved to be less expensive and protected against further scheduled and unscheduled operations

The stem design in total hip arthroplasty (THA) is constantly evolving. The impact of the collar on the risk of periprosthetic fracture remains controversial. This study aimed to determine whether adding a collar to the femoral stem impacts the early periprosthetic fracture risk within 90 days of surgery. This retrospective study included 1,623 patients who underwent primary total hip arthroplasty in a single orthopedic department between January 2010 and December 2020. The inclusion criteria were uncemented stem with or without a collar, in a primary intention, without previous hip surgery with a similar “corail like” design. The assessed data were demographic characteristics (age, gender, number of obese (BMI > 30)), single or dual mobility, the surgical approach, the early complication, particularly the periprosthetic femoral fractures. Of the 1,623 patients, 1,380 received a collared stem (85%), and 243 received a collarless stem (15%). A multivariate analysis was performed to determine the collar's effect on the risk of early periprosthetic fracture (<90 days). Nine (0.55%) early periprosthetic fractures were identified in the whole cohort. There were four fractures (1.65%) in the collarless stem group and five fractures (0.36%) in the collared stem group (p=0,005). One patient required revision surgery in the collared stem group, while two patients required revision surgery in the collarless stem group. The multinomial logistic regression model indicated a statistically significant lower (p<0.05) risk of early periprosthetic fracture within 90 days of surgery in the collared stems group. No other risk factor for early periprosthetic fractures has been identified. Using collared stems in cementless THA protects early periprosthetic femoral fractures within 90 days of surgery

While Oxidized Zirconium (OxZr) femoral heads matched with highly cross-linked polyethylene (XLPE) have demonstrated the lowest rate of revision compared to other bearing couples in the Australian National Joint Registry, it has been postulated that these results may, in part, be due to the fact that a single company offers this bearing option with a limited combination of femoral and acetabular prostheses. The purpose of this study was to assess clinical and radiographic outcomes in a matched cohort of total hip replacements (THR) utilizing an identical cementless femoral stem and acetabular component with either an Oxidized Zirconium (OxZr) or Cobalt-Chrome (CoCr) femoral heads at a minimum of 10 years follow-up. We reviewed our institutional database to identify all patients whom underwent a THR with a single cementless femoral stem, acetabular component, XLPE liner and OxZr femoral head with a minimum of 10 years of follow-up. These were then matched to patients who underwent a THR with identical prosthesis combinations with CoCr femoral head by gender, age and BMI. All patients were prospectively evaluated with WOMAC, SF-12 and Harris Hip Score (HHS) preoperatively and postoperatively at 6 weeks, 3 months, 1 and 2 years and every 2 years thereafter. Charts and radiographs were reviewed to determine the revision rates and survivorship (both all cause and aseptic) at 10 years for both cohorts. Paired analysis was performed to determine if differences exist in patient reported outcomes. There were 208 OxZr THRs identified which were matched with 208 CoCr THRs. There was no difference in average age (OxZr, 54.58 years, CoCr, 54.75 years), gender (OxZr 47.6% female, CoCr 47.6% female), and average body max index (OxZr, 31.36 kg/m2, CoCr, 31.12 kg/m2) between the two cohorts. There were no significant differences preoperatively in any of the outcome scores between the two groups (WOMAC (p=0.449), SF-12 (p=0.379), HHS(p=0.3718)). Both the SF12 (p=0.446) and the WOMAC (p=0.278) were similar between the two groups, however the OxZr THR cohort had slightly better HHS compared to the CoCr THR cohort (92.6 vs. 89.7, p=0.039). With revision for any reason as the end point, there was no significant difference in 10 years survivorship between groups (OxZr 98.5%, CoCr 96.6%, p=0.08). Similarly, aseptic revisions demonstrated comparable survivorship rates at 10 year between the OxZr (99.5%) and CoCr groups (97.6%)(p=0.15). Both THR cohorts demonstrated outstanding survivorship and improvement in patient reported outcomes. The only difference was a slightly better HHS score for the OxZr cohort which may represent selection bias, where OxZr implants were perhaps implanted in more active patients. Implant survivorship was excellent and not dissimilar for both the OxZr and CoCr groups at 10 years. Therefore, with respect to implant longevity at the end of the first decade, there appears to be no clear advantage of OxZr heads compared to CoCr heads when paired with XLPE for patients with similar demographics. Further follow-up into the second and third decade may be required to demonstrate if a difference does exist

Patellofemoral instability (PFI) is a common cause of knee pain and disability in the paediatric population. Patella alta, lateralised tibial tubercle, medial patellofemoral ligament (MPFL) deficiency, genu valgum and trochlear dysplasia are well known risk factors.

A prospective database was created including patients referred through our physiotherapy pathway following first-time patella dislocation. Patella alta and lateralisation of the tibial tuberosity was treated with a Fulkerson-type tibial tubercle osteotomy(TTO). Medial patellofemoral ligament was reconstructed using quads tendon autograft pull-down technique. A modified Sheffield protocol was used postoperatively allowing weightbearing in a hinged knee brace.

Forty patients were identified with 8 patients having bilateral presentations. Male to female ratio was 12:28 with an age range of 4–17 years. Eight patients had congenital PFI, five patients acquired PFI through traumatic patella dislocation and twenty-seven patients developed PFI from recurrent dislocations. Structural abnormalities were found in 38(95%) of patients. Patella alta (Caton-Deschamps index >1.2) was identified in 19(47%) patients, genu valgum in 12(30%) patients, increased tibial tubercle-trochlear groove distance(TT-TG>20mm) was present in 9(22.5%) patients and persistent femoral anteversion(> 20 deg) in 7(17%) patients.

Eight patients were treated with TTO and MPFL reconstruction, three patients with MPFL reconstruction alone and five patients had guided growth for genu valgum correction. Ten patients are awaiting surgery. No postoperative patients had recurrence of PFI at their latest follow up.

PFI is a common problem in the adolescent paediatric population with identifiable structural abnormalities. Correcting structural pathology with surgery leads to predictable and safe outcomes.

Introduction. Degenerative spondylosis (DS) represents a challenging condition to diagnose and treat. There are multiple modalities to investigate DS including X-ray, MRI and CT, but symptoms may not be equivocal to DS to support the clinical findings. The investigation of metastases commonly utilises SPECT/CT for identification of areas of increased osteoblastic activity to denote disease. The aim of the study was to analyse the prevalence of asymptomatic DS in a consecutive hospital cohort of oncology patients who had SPECT/CT for investigation of metastases. Methods. Oncology patients who underwent SPECT/CT at St. George's Hospital were analysed between 2015–2019. Exclusion criteria: back pain, inflammatory disorders, metastases, trauma, infection. Radiology reports were examined for DS and anatomical distribution of tracer uptake. Results. A total of 1182 patients had a Whole-Body SPECT CT used for the spinal analysis. After exclusions (age >80 [n=260], non-cancer [n=318], back pain [n=72]), 522 reports with cancer were utilised. Mean age was 65 (4–80). Age and distribution of DS are given in the table. Conclusion. The prevalence of radiological asymptomatic DS is prevalent in large proportions of patients without back pain, and its incidence increases with age. Approximately 60% of 60 year old and 70% of 70 years old patients have asymptomatic DS in the lumbosarcal region. We conclude that SPECT/CT will detect radiographic degenerative spondylosis in an asymptomatic hospital cohort and this prevalence increase with age. Therefore, this modality of imaging must be utilised with caution when investigating potential pain generators. For any figures or tables, please contact the authors directly

Midfoot arthrodesis is the conventional surgical intervention for midfoot arthritis. Arthrodesis aims to stabilise, realign and fuse the affected joints, providing patients with improved pain and function. Current research neglects the measurement of patient reported outcomes.

This study aimed to investigate objective, and patient reported outcomes of midfoot arthrodesis. The secondary aim was to identify variables predicting the development of non-union.

An automated search of online patient records identified 108 eligible patients (117 feet). The rates of union, re-operations, and complications were calculated using radiographs and medical records. Logistic regression was used to model variables influencing the odds of non-union. All living patients were posted a Manchester Oxford Foot Questionnaire (MOx-FQ), a patient reported outcome assessment. Pre-operative MOx-FQ results were available in a minority of cases. Students t-test was used to compare pre- and post-operative MOx-FQ scores.

The rate of union achieved was 74%. The rate of re-operations was 35%. The rate of complications was 14%. Bone grafts and staple fixation independently impacted the odds of non-union. Bone grafts decreased the odds of non-union, whilst staple fixation increased the odds. This finding agrees with the opinion of other researchers.

We recommend the use of bone grafts, and the avoidance of fixation with staples. Previous attempts have been made to assess patient outcomes. However, this study is the first to use the MOx-FQ, a validated questionnaire. Therefore, this study establishes a baseline for improvements in patient reported outcomes.

Purposes and Background. Musculoskeletal disorders are leading causes of work disability. Our purpose was to develop a predictive model in a cohort from 2012 and validate the model in 2016 data. Methods and Results. Prospectively collected data was used to identify inception cohorts in 2012 (n=1652) and 2016 (n=199). Data from back pain claimants receiving treatment in physiotherapy clinics and the Ontario workers' compensation database were linked. Patients were followed for 1 year. Variables from a back pain questionnaire and clinical, demographic and administrative factors were assessed for predictive value. The outcome was cumulative number of calendar days receiving wage-replacement benefits. Cox regression revealed 8 significant predictors of shorter time on benefits in the 2012 cohort: early intervention (HR=1.51), symptom duration < 31 days (HR=0.88), not in construction industry (HR=1.89), high Low Back Outcome Score (HR=1.03), younger age (HR=0.99), higher benefit rate (HR=1.00), intermittent pain (HR=1.15), no sleep disturbance (HR=1.15). The 2012 model c-statistic was 0.73 with a calibration slope of 0.90 (SE=0.19, p=0.61) in the 2016 data, meaning not significantly different. The c-statistic in the 2016 data was 0.69. Median duration on benefits of those with a high risk score was 129 days in 2012 and 45 days in 2016. Conclusion. The 2012 model had a good fit and calibrated well in the 2016 data. Changes in case management by the WSIB might have resulted in significant differences between the 2012 and 2106 cohort. The difference in duration on benefits could affect treatment decision making in future. Conflicts of interest: IWH is funded by the Ministry of Labour in Ontario. Sources of funding: Funding was provided by the Canadian Institute for Health Research

Reduced cervical spine canal AP diameter is linked to the development of spinal cord injury and myelopathy. This is of particular interest to clinicians in New Zealand, given a unique socio-ethnic make-up and prevalent participation in collision sport. Our study builds upon previous unpublished evidence, by analysing normal cervical spine CT scans to explore morphological differences in the sub-axial cervical spine canal, between New Zealand European, Māori and Paciāca individuals.

670 sub-axial cervical vertebrae (C3-C7) were analysed radiographically using high resolution CT trauma scans, showing no acute pathology with respect to the cervical spine. All measurements were made uPlising mulP-planar reconstruction software to obtain slices parallel to the superior endplate at each vertebral level. Maximal canal diameter was measured in the AP and transverse planes. Statistical analysis was performed using analysis of variance (ANOVA).

We included 250 Maori, 250 NZ European and 170 Paciāca vertebrae (455 male, 215 female). Statistically and clinically signiācant differences were found in sagittal canal diameter between all ethnicities, at all spinal levels. NZ European vertebrae demonstrated the largest AP diameter and Paciāca the smallest, at all levels. Transverse canal diameter showed no signiācant difference between ethnicities, however the raatio of AP:transverse diameter was signiācantly different at all spinal levels except C3. Subjective morphological differences in the shape of the vertebral canal were noted, with Māori and Paciāca patients tending towards a flatter, curved canal shape.

A previous study of 166 patients (Coldham, G. et al. 2006) found cervical canal AP diameter to be narrower in Māori and Paciāca patients than in NZ Europeans. Our study, evaluating the normal population, conārms these differences are likely reflecPve of genuine variation between these ethniciPes. Future research is required to critically evaluate the morphologic differences noted during this study.

Abstract. Objectives. Principal Component Analysis (PCA) is a useful method for analysing human motion data. The objective of this study was to use PCA to quantify the biggest variance in knee kinematics waveforms between a Non-Pathological (NP) group and individuals awaiting High Tibial Osteotomy (HTO) surgery. Methods. Thirty knees (29 participants) who were scheduled for HTO surgery were included in this study. Twenty-eight NP volunteers were recruited into the study. Human motion analysis was performed during level gait using a modified Cleveland marker set. Subjects walked at their self-selected speed for a minimum of 6 successful trials. Knee kinematics were calculated within Visual3D (C-Motion). The first three Principal Components (PCs) of each input variable were selected. Single-component reconstruction was performed alongside representative extremes of each PC to aid interpretation of the biomechanical feature reconstructed by each component. Results. Pre-operatively patient demographics included (age: 50.70 (8.71) years; height: 1.75 (.11) m; body mass: 90.57 (20.17) kg; mTFA: 7.75 (3.72) degrees varus; gait speed: 1.06 (0.23) m/s). The HTO cohort was significantly older and had a higher mass than the NP control participants. For knee kinematics the first three PCs explained 88%, 95% and 89% of the sagittal, frontal, and transverse planes, respectively. The main variances can be explained by sagittal plane magnitude differences, peak swing is associated with toe-off, a reduced knee flexion angle is associated with a longer time spent in stance, pre-HTO remain adducted during stance and pre-HTO patients remain more externally rotated during stance and latter part of swing. Conclusions. This study has introduced PCA in trying to better understand the biomechanical differences between a control group and a cohort with medial knee osteoarthritis varus deformity awaiting HTO. Further analysis will be undertaken using PCA comparing pre- and post-surgery which will be of importance in clinical decision making