The April 2023 Children’s orthopaedics Roundup. 360. looks at: CT scan of the ipsilateral femoral neck in paediatric shaft fractures; Meniscal injuries in skeletally immature children with tibial eminence fractures: a systematic literature review; Post-maturity progression in adolescent idiopathic scoliosis curves of 40° to 50°; Prospective, randomized Ponseti treatment for clubfoot: orthopaedic surgeons versus physical therapists; FIFA 11+ Kids: challenges in implementing a prevention programme; The management of developmental dysplasia of the hip in children aged under three months: a consensus study from the British Society for Children's Orthopaedic Surgery; Early investigation and bracing in developmental dysplasia of the hip impacts maternal wellbeing and breastfeeding; Hip arthrodesis in children: a review of 26 cases with a mean of 20 years’ follow-up

The use of artificial intelligence (AI) is rapidly growing across many domains, of which the medical field is no exception. AI is an umbrella term defining the practical application of algorithms to generate useful output, without the need of human cognition. Owing to the expanding volume of patient information collected, known as ‘big data’, AI is showing promise as a useful tool in healthcare research and across all aspects of patient care pathways. Practical applications in orthopaedic surgery include: diagnostics, such as fracture recognition and tumour detection; predictive models of clinical and patient-reported outcome measures, such as calculating mortality rates and length of hospital stay; and real-time rehabilitation monitoring and surgical training. However, clinicians should remain cognizant of AI’s limitations, as the development of robust reporting and validation frameworks is of paramount importance to prevent avoidable errors and biases. The aim of this review article is to provide a comprehensive understanding of AI and its subfields, as well as to delineate its existing clinical applications in trauma and orthopaedic surgery. Furthermore, this narrative review expands upon the limitations of AI and future direction. Cite this article: Bone Joint Res 2023;12(7):447–454

Aims. This scoping review aims to identify patient-related factors associated with a poorer outcome following total ankle arthroplasty (TAA). Methods. A scoping review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A computer-based literature search was performed in PubMed, Embase, Cochrane trials, and Web of Science. Two reviewers independently performed title/abstract and full-text screening according to predetermined selection criteria. English-language original research studies reporting patient-related factors associated with a poorer outcome following TAA were included. Outcomes were defined as patient-reported outcome measures (PROMs), perioperative complications, and failure. Results. A total of 94 studies reporting 101,552 cases of TAA in 101,177 patients were included. The most common patient-related risk factor associated with poorer outcomes were younger age (21 studies), rheumatoid arthritis (17 studies), and diabetes (16 studies). Of the studies using multivariable regression specifically, the most frequently described risk factors were younger age (12 studies), rheumatoid arthritis (eight studies), diabetes (eight studies), and high BMI (eight studies). Conclusion. When controlling for confounding factors, the most commonly reported risk factors for poor outcome are younger age, rheumatoid arthritis, and comorbidities such as diabetes and increased BMI. These patient-related risk factors reported may be used to facilitate the refinement of patient selection criteria for TAA and inform patient expectations. Cite this article: Bone Joint J 2023;105-B(9):985–992

Aims. Occult (clinical) injuries represent 15% of all scaphoid fractures, posing significant challenges to the clinician. MRI has been suggested as the gold standard for diagnosis, but remains expensive, time-consuming, and is in high demand. Conventional management with immobilization and serial radiography typically results in multiple follow-up attendances to clinic, radiation exposure, and delays return to work. Suboptimal management can result in significant disability and, frequently, litigation. Methods. We present a service evaluation report following the introduction of a quality-improvement themed, streamlined, clinical scaphoid pathway. Patients are offered a removable wrist splint with verbal and written instructions to remove it two weeks following injury, for self-assessment. The persistence of pain is the patient’s guide to ‘opt-in’ and to self-refer for a follow-up appointment with a senior emergency physician. On confirmation of ongoing signs of clinical scaphoid injury, an urgent outpatient ‘fast’-wrist protocol MRI scan is ordered, with instructions to maintain wrist immobilization. Patients with positive scan results are referred for specialist orthopaedic assessment via a virtual fracture clinic. Results. From February 2018 to January 2019, there were 442 patients diagnosed as clinical scaphoid fractures. 122 patients (28%) self-referred back to the emergency department at two weeks. Following clinical review, 53 patients were discharged; MRI was booked for 69 patients (16%). Overall, six patients (< 2% of total; 10% of those scanned) had positive scans for a scaphoid fracture. There were no known missed fractures, long-term non-unions or malunions resulting from this pathway. Costs were saved by avoiding face-to-face clinical review and MRI scanning. Conclusion. A patient-focused opt-in approach is safe and effective to managing the suspected occult (clinical) scaphoid fracture. Cite this article: Bone Jt Open 2024;5(2):117–122

Aims. The standard of wide tumour-like resection for chronic osteomyelitis (COM) has been challenged recently by adequate debridement. This paper reviews the evolution of surgical debridement for long bone COM, and presents the outcome of adequate debridement in a tertiary bone infection unit. Methods. We analyzed the retrospective record review from 2014 to 2020 of patients with long bone COM. All were managed by multidisciplinary infection team (MDT) protocol. Adequate debridement was employed for all cases, and no case of wide resection was included. Results. A total of 53 patients (54 bones) with median age of 45.5 years (interquartile range 31 to 55) and mean follow-up of 29 months (12 to 59) were included. In all, ten bones were Cierny-Mader type I, 39 were type III, and five were type IV. All patients were treated with single-staged management, except for one (planned two-stage stabilization). Positive microbial cultures grew in 75%. Overall, 46 cases (85%) had resolution of COM after index procedure, and 49 (90.7%) had resolution on last follow-up. Four patients (7%) underwent second surgical procedure and six patients (11%) had complications. Conclusion. We challenge the need for wide tumour-like resection in all cases of COM. Through detailed preoperative evaluation and planning with MDT approach, adequate debridement and local delivery of high concentration of antibiotic appears to provide comparable outcomes versus radical debridement. Cite this article: Bone Jt Open 2023;4(8):643–651

Aims. Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes. Methods. A systematic review identified a list of measurements previously used in studies reporting radiological hip outcomes in children with CP. These measurements informed a two-round Delphi study, conducted among orthopaedic surgeons and specialist physiotherapists. Participants rated each measurement on a nine-point Likert scale (‘not important’ to ‘critically important’). A consensus meeting was held to finalize the CMS. Results. Overall, 14 distinct measurements were identified in the systematic review, with Reimer’s migration percentage being the most frequently reported. These measurements were presented over the two rounds of the Delphi process, along with two additional measurements that were suggested by participants. Ultimately, two measurements, Reimer’s migration percentage and femoral head-shaft angle, were included in the CMS. Conclusion. This use of a minimum standardized set of measurements has the potential to encourage uniformity across hip surveillance programmes, and may streamline the development of tools, such as artificial intelligence systems to automate the analysis in surveillance programmes. This core set should be the minimum requirement in clinical studies, allowing clinicians to add to this as needed, which will facilitate comparisons to be drawn between studies and future meta-analyses. Cite this article: Bone Jt Open 2023;4(11):825–831

Aims. In the UK, the agricultural, military, and construction sectors have stringent rules about the use of hearing protection due to the risk of noise-induced hearing loss. Orthopaedic staff may also be at risk due to the use of power tools. The UK Health and Safety Executive (HSE) have clear standards as to what are deemed acceptable occupational levels of noise on A-weighted and C-weighted scales. The aims of this review were to assess the current evidence on the testing of exposure to noise in orthopaedic operating theatres to see if it exceeds these regulations. Methods. A search of PubMed and EMBASE databases was conducted using PRISMA guidelines. The review was registered prospectively in PROSPERO. Studies which assessed the exposure to noise for orthopaedic staff in operating theatres were included. Data about the exposure to noise were extracted from these studies and compared with the A-weighted and C-weighted acceptable levels described in the HSE regulations. Results. A total of 15 studies were deemed eligible. These included a total of 386 orthopaedic operations and the use of 64 orthopaedic instruments. A total of 294 operations (76%) and 45 instruments (70%) exceeded the regulations on an A-weighted scale, and 22% (10 of 46) of operations exceeded the maximum C-weighted peak acceptable level of noise. Noise-induced hearing loss was reported in 28 of 55 orthopaedic staff members (50.9%). Conclusion. Safe levels of noise can be exceeded in orthopaedic operations, and when using orthopaedic instruments. Employers have clear policies about exposure to noise in the workplace but have yet to identify orthopaedic theatres as a potential at-risk area. Orthopaedic staff need education, monitoring, and protection, while employers should consider regular assessments of staff in orthopaedic theatres and offer methods to prevent noise-induced hearing loss. Cite this article: Bone Joint J 2023;105-B(6):602–609

Aims. Children with spinal dysraphism can develop various musculoskeletal deformities, necessitating a range of orthopaedic interventions, causing significant morbidity, and making considerable demands on resources. This systematic review aimed to identify what outcome measures have been reported in the literature for children with spinal dysraphism who undergo orthopaedic interventions involving the lower limbs. Methods. A PROSPERO-registered systematic literature review was performed following PRISMA guidelines. All relevant studies published until January 2023 were identified. Individual outcomes and outcome measurement tools were extracted verbatim. The measurement tools were assessed for reliability and validity, and all outcomes were grouped according to the Outcome Measures Recommended for use in Randomized Clinical Trials (OMERACT) filters. Results. From 91 eligible studies, 27 individual outcomes were identified, including those related to clinical assessment (n = 12), mobility (n = 4), adverse events (n = 6), investigations (n = 4), and miscellaneous (n = 1). Ten outcome measurement tools were identified, of which Hoffer’s Functional Ambulation Scale was the most commonly used. Several studies used unvalidated measurement tools originally developed for other conditions, and 26 studies developed new measurement tools. On the OMERACT filter, most outcomes reported pathophysiology and/or the impact on life. There were only six patient- or parent-reported outcomes, and none assessed the quality of life. Conclusion. The outcomes that were reported were heterogenous, lack validation and failed to incorporate patient or family perceptions. Until outcomes can be reported unequivocally, research in this area will remain limited. Our findings should guide the development of a core outcome set, which will allow consistency in the reporting of outcomes for this condition. Cite this article: Bone Joint J 2024;106-B(3):277–285

Aims. This systematic review aimed to summarize the full range of complications reported following ankle arthroscopy and the frequency at which they occur. Methods. A computer-based search was performed in PubMed, Embase, Emcare, and ISI Web of Science. Two-stage title/abstract and full-text screening was performed independently by two reviewers. English-language original research studies reporting perioperative complications in a cohort of at least ten patients undergoing ankle arthroscopy were included. Complications were pooled across included studies in order to derive an overall complication rate. Quality assessment was performed using the Oxford Centre for Evidence-Based Medicine levels of evidence classification. Results. A total of 150 studies describing 7,942 cases of ankle arthroscopy in 7,777 patients were included. The overall pooled complication rate was 325/7,942 (4.09%). The most common complication was neurological injury, accounting for 180/325 (55.4%) of all complications. Of these, 59 (32.7%) affected the superficial peroneal nerve. Overall, 36/180 (20%) of all nerve injuries were permanent. The overall complication rate following anterior ankle arthroscopy was 205/4,709 (4.35%) compared to a rate of 35/528 (6.6%) following posterior arthroscopy. Neurological injury occurred in 52/1,998 (2.6%) of anterior cases using distraction, compared to 59/2,711 (2.2%) in cases with no distraction. The overall rate of major complications was 16/7,942 (0.2%), with the most common major complication – deep vein thrombosis – occurring in five cases. Conclusion. This comprehensive systematic review demonstrates that ankle arthroscopy is a safe procedure with a low overall complication rate. The majority of complications are minor, with potentially life-threatening complications reported in only 0.2% of patients. Cite this article: Bone Joint J 2023;105-B(3):239–246

Aims. Perthes' disease (PD) is a relatively rare syndrome of idiopathic osteonecrosis of the proximal femoral epiphysis. Treatment for Perthes' disease is controversial due to the many options available, with no clear superiority of one treatment over another. Despite having few evidence-based approaches, many patients with Perthes' disease are managed surgically. Positive outcome reporting, defined as reporting a study variable producing statistically significant positive (beneficial) results, is a phenomenon that can be considered a proxy for the strength of science. This study aims to conduct a systematic literature review with the hypothesis that positive outcome reporting is frequent in studies on the treatment of Perthes' disease. Methods. We conducted a systematic review of all available abstracts associated with manuscripts in English or with English translation between January 2000 and December 2021, dealing with the treatment of Perthes' disease. Data collection included various study characteristics, surgical versus non-surgical management, treatment modality, mean follow-up time, analysis methods, and clinical recommendations. Results. Our study included 130 manuscripts. Overall, 110 (85%) reported positive (beneficial) results, three (2%) reported negative results, and 17 (13%) reported no significant difference. Despite only 10/130 studies (8%) having a testable hypothesis, 71 (55%) recommended the use of their studied treatment methods for the patients, five (4%) made recommendations against the use of the studied treatment modality, and 54 (42%) did not make any recommendations. Conclusion. The overall rate for positive outcomes among included manuscripts regarding different treatment methods for Perthes' disease (85%) is higher than the 74% positive outcome rate found among studies for other surgically treated disorders and significantly higher than most scientific literature. Despite the lack of testable hypotheses, most manuscripts recommended their studied treatment method as a successful option for managing patients solely based on the reporting of retrospective data. Cite this article: Bone Joint J 2024;106-B(2):121–127

Aims. The aim of this study was to develop a core outcome set of what to measure in all future clinical research on hand fractures and joint injuries in adults. Methods. Phase 1 consisted of steps to identify potential outcome domains through systematic review of published studies, and exploration of the patient perspective through qualitative research, consisting of 25 semi-structured interviews and five focus groups. Phase 2 involved key stakeholder groups (patients, hand surgeons, and hand therapists) prioritizing the outcome domains via a three-round international Delphi survey, with a final consensus meeting to agree the final core outcome set. Results. The systematic review of 160 studies identified 74 outcome domains based on the World Health Organization International Classification of Functioning, Disability, and Health. Overall, 35 domains were generated through thematic analysis of the patient interviews and focus groups. The domains from these elements were synthesised to develop 37 outcome domains as the basis of the Delphi survey, with a further four generated from participant suggestions in Round 1. The Delphi survey identified 20 outcome domains as ‘very important’ for the core outcome set. At the consensus meeting, 27 participants from key stakeholder groups selected seven outcomes for the core outcome set: pain/discomfort with activity, pain/discomfort with rest, fine hand use/dexterity, self-hygiene/personal care, return to usual work/job, range of motion, and patient satisfaction with outcome/result. Conclusion. This set of core outcome domains is recommended as a minimum to be reported in all clinical research on hand fractures and joint injuries in adults. While this establishes what to measure, future work will focus on determining how best to measure these outcomes. By adopting this patient-centred core outcome set, consistency and comparability of studies will be improved, aiding meta-analysis and strengthening the evidence base for management of these common and impactful injuries. Cite this article: Bone Jt Open 2023;4(2):87–95

Aims. To clarify the mid-term results of transposition osteotomy of the acetabulum (TOA), a type of spherical periacetabular osteotomy, combined with structural allograft bone grafting for severe hip dysplasia. Methods. We reviewed patients with severe hip dysplasia, defined as Severin IVb or V (lateral centre-edge angle (LCEA) < 0°), who underwent TOA with a structural bone allograft between 1998 and 2019. A medical chart review was conducted to extract demographic data, complications related to the osteotomy, and modified Harris Hip Score (mHHS). Radiological parameters of hip dysplasia were measured on pre- and postoperative radiographs. The cumulative probability of TOA failure (progression to Tönnis grade 3 or conversion to total hip arthroplasty) was estimated using the Kaplan–Meier product-limited method, and a multivariate Cox proportional hazard model was used to identify predictors for failure. Results. A total of 64 patients (76 hips) were included in this study. The median follow-up period was ten years (interquartile range (IQR) five to 14). The median mHHS improved from 67 (IQR 56 to 80) preoperatively to 96 (IQR 85 to 97) at the latest follow-up (p < 0.001). The radiological parameters improved postoperatively (p < 0.001), with the resulting parameters falling within the normal range in 42% to 95% of hips. The survival rate was 95% at ten years and 80% at 15 years. Preoperative Tönnis grade 2 was an independent risk factor for TOA failure. Conclusion. Our findings suggest that TOA with structural bone allografting is a viable surgical option for correcting severely dysplastic acetabulum in adolescents and young adults without advanced osteoarthritis, with favourable mid-term outcomes. Cite this article: Bone Joint J 2023;105-B(7):743–750

Aims. The ‘pink, pulseless hand’ is often used to describe the clinical situation in which a child with a supracondylar fracture of the humerus has normal distal perfusion in the absence of a palpable peripheral pulse. The management guidelines are based on the assessment of perfusion, which is difficult to undertake and poorly evaluated objectively. The aim of this study was to review the available literature in order to explore the techniques available for the preoperative clinical assessment of perfusion in these patients and to evaluate the clinical implications. Methods. A systematic literature review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and registered prospectively with the International Prospective Register of Systematic Reviews. Databases were explored in June 2022 with the search terms (pulseless OR dysvascular OR ischaemic OR perfused OR vascular injury) AND supracondylar AND (fracture OR fractures). Results. A total of 573 papers were identified as being suitable for further study, and 25 met the inclusion criteria for detailed analysis. These studies included a total of 504 patients with a perfused, pulseless limb associated with a supracondylar humeral fracture. Clinical examination included skin colour (23 studies (92%)), temperature (16 studies (64%)), and capillary refill time (13 studies (52%)). Other investigations included peripheral oxygen saturation (SaO2) (six studies (24%)), ultrasound (US) (14 (56%)), and CT angiogram (two studies (8.0%)). The parameters of ‘normal perfusion’ were often not objectively defined. The time to surgery ranged from 1.5 to 12 hours. A total of 412 patients (82%) were definitively treated with closed or open reduction and fixation, and 92 (18%) required vascular intervention, ranging from simple release of entrapped vessels to vascular grafts. Conclusion. The description of the vascular assessment of the patient with a supracondylar humeral fracture and a pulseless limb in the literature is variable, with few objective criteria being used to define perfusion. The evidence base for decision-making is limited, and further research is required. We were able, however, to make some recommendations about objective criteria for the assessment of these patients, and we suggest that these are performed frequently to allow the detection of any deterioration of perfusion. Cite this article: Bone Joint J 2023;105-B(3):231–238

Aims. Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. Methods. We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. Results. Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. Conclusion. Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation. Cite this article: Bone Jt Open 2022;3(12):991–997

Aims. The aim of this study was to perform a systematic review of the evidence for the use of intraoperative cell salvage in patients undergoing revision hip arthroplasty, and specifically to analyze the available data in order to quantify any associated reduction in the use of allogenic blood transfusion, and the volume which is used. Methods. An electronic search of MEDLINE (PubMed), Embase, Scopus, and the Cochrane Library was completed from the date of their inception to 24 February 2022, using a search strategy and protocol created in conjunction with the PRISMA statement. Inclusion criteria were patients aged > 18 years who underwent revision hip arthroplasty when cell salvage was used. Studies in which pre-donated red blood cells were used were excluded. A meta-analysis was also performed using a random effects model with significance set at p = 0.05. Results. Of the 283 studies which were identified, 11 were included in the systematic review, and nine in the meta-analysis. There was a significant difference (p < 0.001) in the proportion of patients requiring allogenic transfusion between groups, with an odds ratio of 0.331 (95% confidence interval (CI) 0.165 to 0.663) associated with the use of cell salvage. For a total of 561 patients undergoing revision hip arthroplasty who were treated with cell salvage, 247 (44.0%) required allogenic transfusion compared with 418 of 643 patients (65.0%) who were treated without cell salvage. For those treated with cell salvage, the mean volume of allogenic blood which was required was 1.95 units (390 ml) per patient (0.7 to 4.5 units), compared with 3.25 units (650 ml) per patient (1.2 to 7.0 units) in those treated without cell salvage. The mean difference of -1.91 units (95% CI -4.0 to 0.2) in the meta-analysis was also significant (p = 0.003). Conclusion. We found a a significant reduction in the need for allogenic blood transfusion when cell salvage was used in patients undergoing revision hip arthroplasty, supporting its routine use in these patients. Further research is required to determine whether this effect is associated with types of revision arthroplasty of differing complexity. Cite this article: Bone Joint J 2023;105-B(10):1038–1044

Aims. The aim of this study was to determine the clinical outcomes and factors contributing to failure of transposition osteotomy of the acetabulum (TOA), a type of spherical periacetabular osteotomy, for advanced osteoarthritis secondary to hip dysplasia. Methods. We reviewed patients with Tönnis grade 2 osteoarthritis secondary to hip dysplasia who underwent TOA between November 1998 and December 2019. Patient demographic details, osteotomy-related complications, and the modified Harris Hip Score (mHHS) were obtained via medical notes review. Radiological indicators of hip dysplasia were assessed using preoperative and postoperative radiographs. The cumulative probability of TOA failure (progression to Tönnis grade 3 or conversion to total hip arthroplasty) was estimated using the Kaplan-Meier product-limited method. A multivariate Cox proportional hazards model was used to identify predictors of failure. Results. This study included 127 patients (137 hips). Median follow-up period was ten years (IQR 6 to 15). The median mHHS improved from 59 (IQR 52 to 70) preoperatively to 90 (IQR 73 to 96) at the latest follow-up (p < 0.001). The survival rate was 90% (95% CI 82 to 95) at ten years, decreasing to 21% (95% CI 7 to 48) at 20 years. Fair joint congruity on preoperative hip abduction radiographs and a decreased postoperative anterior wall index (AWI) were identified as independent risk factors for failure. The survival rate for the 42 hips with good preoperative joint congruity and a postoperative AWI ≥ 0.30 was 100% at ten years, and remained at 83% (95% CI 38 to 98) at 20 years. Conclusion. Although the overall clinical outcomes of TOA in patients with advanced osteoarthritis are suboptimal, favourable results can be achieved in selected cases with good preoperative joint congruity and adequate postoperative anterior acetabular coverage. Cite this article: Bone Joint J 2024;106-B(8):783–791

Aims. It has been well documented in the arthroplasty literature that lumbar degenerative disc disease (DDD) contributes to abnormal spinopelvic motion. However, the relationship between the severity or pattern of hip osteoarthritis (OA) as measured on an anteroposterior (AP) pelvic view and spinopelvic biomechanics has not been well investigated. Therefore, the aim of the study is to examine the association between the severity and pattern of hip OA and spinopelvic motion. Methods. A retrospective chart review was conducted to identify patients undergoing primary total hip arthroplasty (THA). Plain AP pelvic radiographs were reviewed to document the morphological characteristic of osteoarthritic hips. Lateral spine-pelvis-hip sitting and standing plain radiographs were used to measure sacral slope (SS) and pelvic femoral angle (PFA) in each position. Lumbar disc spaces were measured to determine the presence of DDD. The difference between sitting and standing SS and PFA were calculated to quantify spinopelvic motion (ΔSS) and hip motion (ΔPFA), respectively. Univariate analysis and Pearson correlation were used to identify morphological hip characteristics associated with changes in spinopelvic motion. Results. In total, 139 patients were included. Increased spinopelvic motion was observed in patients with loss of femoral head contour, cam deformity, and acetabular bone loss (all p < 0.05). Loss of hip motion was observed in patients with loss of femoral head contour, cam deformity, and acetabular bone loss (all p < 0.001). A decreased joint space was associated with a decreased ΔPFA (p = 0.040). The presence of disc space narrowing, disc space narrowing > two levels, and disc narrowing involving the L5–S1 segment were associated with decreased spinopelvic motion (all p < 0.05). Conclusion. Preoperative hip OA as assessed on an AP pelvic radiograph predicts spinopelvic motion. These data suggest that specific hip osteoarthritic morphological characteristics listed above alter spinopelvic motion to a greater extent than others. Cite this article: Bone Joint J 2023;105-B(5):496–503

Aims. Venous tumour thrombus (VTT) is a rare finding in osteosarcoma. Despite the high rate of VTT in osteosarcoma of the pelvis, there are very few descriptions of VTT associated with extrapelvic primary osteosarcoma. We therefore sought to describe the prevalence and presenting features of VTT in osteosarcoma of both the pelvis and the limbs. Methods. Records from a single institution were retrospectively reviewed for 308 patients with osteosarcoma of the pelvis or limb treated between January 2000 and December 2022. Primary lesions were located in an upper limb (n = 40), lower limb (n = 198), or pelvis (n = 70). Preoperative imaging and operative reports were reviewed to identify patients with thrombi in proximity to their primary lesion. Imaging and histopathology were used to determine presence of tumour within the thrombus. Results. Tumours abutted the blood vessels in 131 patients (43%) and encased the vessels in 30 (10%). Any form of venous thrombus was identified in 31 patients (10%). Overall, 21 of these thrombi were determined to be involved with the tumour based on imaging (n = 9) or histopathology (n = 12). The rate of VTT was 25% for pelvic osteosarcoma and 1.7% for limb osteosarcoma. The most common imaging features associated with histopathologically proven VTT were enhancement with contrast (n = 12; 100%), venous enlargement (n = 10; 83%), vessel encasement (n = 8; 66%), and visible intraluminal osteoid matrix (n = 6; 50%). Disease-specific survival (DSS) for patients with VTT was 95% at 12 months (95% CI 0.87 to 1.00), 50% at three years (95% CI 0.31 to 0.80), and 31% at five years (95% CI 0.14 to 0.71). VTT was associated with worse DSS (hazard ratio 2.3 (95% CI 1.11 to 4.84). Conclusion. VTT is rare with osteosarcoma and occurs more commonly in the pelvis than the limbs. Imaging features suggestive of VTT include enhancement with contrast, venous dilation, and vessel encasement. VTT portends a worse prognosis for patients with osteosarcoma, with a similar survivability to metastatic disease. Cite this article: Bone Joint J 2024;106-B(8):865–870

Aims. This systematic review and meta-analysis aimed to compare the influence of patellar resurfacing following cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty (TKA) on the incidence of anterior knee pain, knee-specific patient-reported outcome measures, complication rates, and reoperation rates. Methods. A systematic review of MEDLINE, PubMed, and Google Scholar was performed to identify randomized controlled trials (RCTs) according to search criteria. Search terms used included: arthroplasty, replacement, knee (Mesh), TKA, prosthesis, patella, patellar resurfacing, and patellar retaining. RCTs that compared patellar resurfacing versus unresurfaced in primary TKA were included for further analysis. Studies were evaluated using the Scottish Intercollegiate Guidelines Network assessment tool for quality and minimization of bias. Data were synthesized and meta-analysis performed. Results. There were 4,135 TKAs (2,068 resurfaced and 2,027 unresurfaced) identified in 35 separate cohorts from 33 peer-reviewed studies. Anterior knee pain rates were significantly higher in unresurfaced knees overall (odds ratio (OR) 1.84; 95% confidence interval (CI) 1.20 to 2.83; p = 0.006) but more specifically associated with CR implants (OR 1.95; 95% CI 1.0 to 3.52; p = 0.030). There was a significantly better Knee Society function score (mean difference (MD) -1.98; 95% CI -1.1 to -2.84; p < 0.001) and Oxford Knee Score (MD -2.24; 95% CI -0.07 to -4.41; p = 0.040) for PS implants when patellar resurfacing was performed, but these differences did not exceed the minimal clinically important difference for these scores. There were no significant differences in complication rates or infection rates according to implant design. There was an overall significantly higher reoperation rate for unresurfaced TKA (OR 1.46 (95% CI 1.04 to 2.06); p = 0.030) but there was no difference between PS or CR TKA. Conclusion. Patellar resurfacing, when performed with CR implants, resulted in lower rates of anterior knee pain and, when used with a PS implant, yielded better knee-specific functional outcomes. Patellar resurfacing was associated with a lower risk of reoperation overall, but implant type did not influence this. Cite this article: Bone Joint J 2023;105-B(6):622–634