Aims

There are comparatively few randomized studies evaluating knee arthroplasty prostheses, and fewer still that report longer-term functional outcomes. The aim of this study was to evaluate mid-term outcomes of an existing implant trial cohort to document changing patient function over time following total knee arthroplasty using longitudinal analytical techniques and to determine whether implant design chosen at time of surgery influenced these outcomes.

Aims. This study aimed to evaluate the effectiveness of the induced membrane technique for treating infected bone defects, and to explore the factors that might affect patient outcomes. Methods. A comprehensive search was performed in PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases between 1 January 2000 and 31 October 2021. Studies with a minimum sample size of five patients with infected bone defects treated with the induced membrane technique were included. Factors associated with nonunion, infection recurrence, and additional procedures were identified using logistic regression analysis on individual patient data. Results. After the screening, 44 studies were included with 1,079 patients and 1,083 segments of infected bone defects treated with the induced membrane technique. The mean defect size was 6.8 cm (0.5 to 30). After the index second stage procedure, 85% (797/942) of segments achieved union, and 92% (999/1,083) of segments achieved final healing. The multivariate analysis with data from 296 patients suggested that older age was associated with higher nonunion risk. Patients with external fixation in the second stage had a significantly higher risk of developing nonunion, increasing the need for additional procedures. The autografts harvested from the femur reamer-irrigator-aspirator increased nonunion, infection recurrence, and additional procedure rates. Conclusion. The induced membrane technique is an effective technique for treating infected bone defects. Internal fixation during the second stage might effectively promote bone healing and reduce additional procedures without increasing infection recurrence. Future studies should standardize individual patient data prospectively to facilitate research on the affected patient outcomes. Cite this article: Bone Joint Res 2023;12(9):546–558

Aims. Machine learning (ML) holds significant promise in optimizing various aspects of total shoulder arthroplasty (TSA), potentially improving patient outcomes and enhancing surgical decision-making. The aim of this systematic review was to identify ML algorithms and evaluate their effectiveness, including those for predicting clinical outcomes and those used in image analysis. Methods. We searched the PubMed, EMBASE, and Cochrane Central Register of Controlled Trials databases for studies applying ML algorithms in TSA. The analysis focused on dataset characteristics, relevant subspecialties, specific ML algorithms used, and their performance outcomes. Results. Following the final screening process, 25 articles satisfied the eligibility criteria for our review. Of these, 60% focused on tabular data while the remaining 40% analyzed image data. Among them, 16 studies were dedicated to developing new models and nine used transfer learning to leverage existing pretrained models. Additionally, three of these models underwent external validation to confirm their reliability and effectiveness. Conclusion. ML algorithms used in TSA demonstrated fair to good performance, as evidenced by the reported metrics. Integrating these models into daily clinical practice could revolutionize TSA, enhancing both surgical precision and patient outcome predictions. Despite their potential, the lack of transparency and generalizability in many current models poses a significant challenge, limiting their clinical utility. Future research should prioritize addressing these limitations to truly propel the field forward and maximize the benefits of ML in enhancing patient care. Cite this article: Bone Jt Open 2025;6(2):126–134

Aims. To identify variables independently associated with same-day discharge (SDD) of patients following revision total knee arthroplasty (rTKA) and to develop machine learning algorithms to predict suitable candidates for outpatient rTKA. Methods. Data were obtained from the American College of Surgeons National Quality Improvement Programme (ACS-NSQIP) database from the years 2018 to 2020. Patients with elective, unilateral rTKA procedures and a total hospital length of stay between zero and four days were included. Demographic, preoperative, and intraoperative variables were analyzed. A multivariable logistic regression (MLR) model and various machine learning techniques were compared using area under the curve (AUC), calibration, and decision curve analysis. Important and significant variables were identified from the models. Results. Of the 5,600 patients included in this study, 342 (6.1%) underwent SDD. The random forest (RF) model performed the best overall, with an internally validated AUC of 0.810. The ten crucial factors favoring SDD in the RF model include operating time, anaesthesia type, age, BMI, American Society of Anesthesiologists grade, race, history of diabetes, rTKA type, sex, and smoking status. Eight of these variables were also found to be significant in the MLR model. Conclusion. The RF model displayed excellent accuracy and identified clinically important variables for determining candidates for SDD following rTKA. Machine learning techniques such as RF will allow clinicians to accurately risk-stratify their patients preoperatively, in order to optimize resources and improve patient outcomes. Cite this article: Bone Jt Open 2023;4(6):399–407

Aims. The evidence base within trauma and orthopaedics has traditionally favoured quantitative research methodologies. Qualitative research can provide unique insights which illuminate patient experiences and perceptions of care. Qualitative methods reveal the subjective narratives of patients that are not captured by quantitative data, providing a more comprehensive understanding of patient-centred care. The aim of this study is to quantify the level of qualitative research within the orthopaedic literature. Methods. A bibliometric search of journals’ online archives and multiple databases was undertaken in March 2024, to identify articles using qualitative research methods in the top 12 trauma and orthopaedic journals based on the 2023 impact factor and SCImago rating. The bibliometric search was conducted and reported in accordance with the preliminary guideline for reporting bibliometric reviews of the biomedical literature (BIBLIO). Results. Of the 7,201 papers reviewed, 136 included qualitative methods (0.1%). There was no significant difference between the journals, apart from Bone & Joint Open, which included 21 studies using qualitative methods, equalling 4% of its published articles. Conclusion. This study demonstrates that there is a very low number of qualitative research papers published within trauma and orthopaedic journals. Given the increasing focus on patient outcomes and improving the patient experience, it may be argued that there is a requirement to support both quantitative and qualitative approaches to orthopaedic research. Combining qualitative and quantitative methods may effectively address the complex and personal aspects of patients’ care, ensuring that outcomes align with patient values and enhance overall care quality

Aims. The goal was to evaluate tibiofemoral knee joint kinematics during stair descent, by simulating the full stair descent motion in vitro. The knee joint kinematics were evaluated for two types of knee implants: bi-cruciate retaining and bi-cruciate stabilized. It was hypothesized that the bi-cruciate retaining implant better approximates native kinematics. Methods. The in vitro study included 20 specimens which were tested during a full stair descent with physiological muscle forces in a dynamic knee rig. Laxity envelopes were measured by applying external loading conditions in varus/valgus and internal/external direction. Results. The laxity results show that both implants are capable of mimicking the native internal/external-laxity during the controlled lowering phase. The kinematic results show that the bi-cruciate retaining implant tends to approximate the native condition better compared to bi-cruciate stabilized implant. This is valid for the internal/external rotation and the anteroposterior translation during all phases of the stair descent, and for the compression-distraction of the knee joint during swing and controlled lowering phase. Conclusion. The results show a better approximation of the native kinematics by the bi-cruciate retaining knee implant compared to the bi-cruciate stabilized knee implant for internal/external rotation and anteroposterior translation. Whether this will result in better patient outcomes remains to be investigated. Cite this article: Bone Joint Res 2023;12(4):285–293

Aims. The aims of the study were to report for a cohort aged younger than 40 years: 1) indications for HRA; 2) patient-reported outcomes in terms of the modified Harris Hip Score (HHS); 3) dislocation rate; and 4) revision rate. Methods. This retrospective analysis identified 267 hips from 224 patients who underwent an hip resurfacing arthroplasty (HRA) from a single fellowship-trained surgeon using the direct lateral approach between 2007 and 2019. Inclusion criteria was minimum two-year follow-up, and age younger than 40 years. Patients were followed using a prospectively maintained institutional database. Results. A total of 217 hips (81%) were included for follow-up analysis at a mean of 3.8 years. Of the 23 females who underwent HRA, none were revised, and the median head size was 46 mm (compared to 50 mm for males). The most common indication for HRA was femoroacetabular impingement syndrome (n = 133), and avascular necrosis ( (n = 53). Mean postoperative HHS was 100 at two and five years. No dislocations occurred. A total of four hips (1.8%) required reoperation for resection of heterotopic ossification, removal of components for infection, and subsidence with loosening. The overall revision rate was 0.9%. Conclusion. For younger patients with higher functional expectations and increased lifetime risk for revision, HRA is an excellent bone preserving intervention carrying low complication rates, revision rates, and excellent patient outcomes without lifetime restrictions allowing these patients to return to activity and sport. Thus, in younger male patients with end-stage hip disease and higher demands, referral to a high-volume HRA surgeon should be considered. Cite this article: Bone Jt Open 2023;4(6):408–415

Aims. Posterior malleolar (PM) fractures are commonly associated with ankle fractures, pilon fractures, and to a lesser extent tibial shaft fractures. The tibialis posterior (TP) tendon entrapment is a rare complication associated with PM fractures. If undiagnosed, TP entrapment is associated with complications, ranging from reduced range of ankle movement to instability and pes planus deformities, which require further surgeries including radical treatments such as arthrodesis. Methods. The inclusion criteria applied in PubMed, Scopus, and Medline database searches were: all adult studies published between 2012 and 2022; and studies written in English. Outcome of TP entrapment in patients with ankle injuries was assessed by two reviewers independently. Results. Four retrospective studies and eight case reports were accepted in this systematic review. Collectively there were 489 Pilon fractures, 77 of which presented with TP entrapment (15.75%). There were 28 trimalleolar fractures, 12 of which presented with TP entrapment (42.86%). All the case report studies reported inability to reduce the fractures at initial presentation. The diagnosis of TP entrapment was made in the early period in two (25%) cases, and delayed diagnosis in six (75%) cases reported. Using modified Clavien-Dindo complication classification, 60 (67%) of the injuries reported grade IIIa complications and 29 (33%) grade IIIb complications. Conclusion. TP tendon was the commonest tendon injury associated with pilon fracture and, to a lesser extent, trimalleolar ankle fracture. Early identification using a clinical suspicion and CT imaging could lead to early management of TP entrapment in these injuries, which could lead to better patient outcomes and reduced morbidity. Cite this article: Bone Jt Open 2024;5(3):252–259

Aims. The Birmingham Orthopaedic Oncology Meeting (BOOM), held in January 2024, convened 309 delegates from 53 countries to discuss and refine 21 consensus statements on the optimal management of chondrosarcoma. Methods. With representation from Europe (43%; n = 133), North America (17%; n = 53), South America (16%; n = 49), Asia (13%; n = 40), Australasia (5%; n = 16), the Middle East (4%; n = 12), and Africa (2%; n = 6), the combined experience of treating bone sarcomas among attendees totalled approximately 30,000 cases annually, equivalent to 66 years of experience in the UK alone. The meeting’s process began with the formation of a local organizing committee, regional leads, and a scientific committee comprising representatives from 150 specialist units across 47 countries. Supported by major orthopaedic oncology organizations, the meeting used a modified Delphi process to develop consensus statements through online questionnaires, thematic groupings, narrative reviews, and anonymous pre-meeting polling. Results. Strong (> 80%) consensus was achieved on 19 out of 21 statements, reflecting agreement among delegates. Key areas of consensus included the role of radiology in diagnosis and surveillance, the management of locally recurrent disease, and the treatment of dedifferentiated chondrosarcoma. Notably, there was agreement that routine chemotherapy has no role in chondrosarcoma treatment, and radiological surveillance is safe for intraosseous chondrosarcomas. Despite the overall consensus, areas of controversy remain, particularly regarding the treatment of atypical cartilage tumours and surgical margins. These unresolved issues underscore the need for further research and collaboration within the orthopaedic oncology community. Conclusion. BOOM represents the largest global consensus meeting in orthopaedic oncology, providing valuable guidance for clinicians managing chondrosarcoma worldwide. The consensus statements offer a reference for clinical practice, highlight key research priorities, and aim to improve patient outcomes on a global scale. Cite this article: Bone Joint J 2025;107-B(2):246–252

Aims. The modern prevalence of primary tumours causing metastatic bone disease is ill-defined in the oncological literature. Therefore, the purpose of this study is to identify the prevalence of primary tumours in the setting of metastatic bone disease, as well as reported rates of pathological fracture, postoperative complications, 90-day mortality, and 360-day mortality for each primary tumour subtype. Methods. The Premier Healthcare Database was queried to identify all patients who were diagnosed with metastatic bone disease from January 2015 to December 2020. The prevalence of all primary tumour subtypes was tabulated. Rates of long bone pathological fracture, 90-day mortality, and 360-day mortality following surgical treatment of pathological fracture were assessed for each primary tumour subtype. Patient characteristics and postoperative outcomes were analyzed based upon whether patients had impending fractures treated prophylactically versus treated completed fractures. Results. In total, 407,893 unique patients with metastatic bone disease were identified. Of the 14 primary tumours assessed, metastatic bone disease most frequently originated from lung (24.8%), prostatic (19.4%), breast (19.3%), gastrointestinal (9.4%), and urological (6.5%) malignancies. The top five malignant tumours resulting in long bone pathological fracture were renal (5.8%), myeloma (3.4%), female reproductive (3.2%), lung (2.8%), and breast (2.7%). Following treatment of pathological fractures of long bones, 90-day mortality rates were greatest for lung (12.1%), central nervous system (10.5%), lymphoma (10.4%), gastrointestinal (10.1%), and non-renal urinary (10.0%) malignancies. Finally, our study demonstrates improved 90-day and 360-day survival in patients treated for impending pathological fracture compared to completed fracture, as well as significantly lower rates of deep vein thrombosis, pulmonary embolism, urinary tract infection, and blood transfusion. Conclusion. This study defines the contemporary characteristics of primary malignancies resulting in metastatic bone disease. These data should be considered by surgeons when prognosticating patient outcomes during treatment of their metastatic bone disease. Cite this article: Bone Jt Open 2023;4(6):424–431

Aims. The aim of this study was to explore clinicians’ experience of a paediatric randomized controlled trial (RCT) comparing surgical reduction with non-surgical casting for displaced distal radius fractures. Methods. Overall, 22 staff from 15 hospitals who participated in the RCT took part in an interview. Interviews were informed by phenomenology and analyzed using thematic analysis. Results. Analysis of the findings identified the overarching theme of “overcoming obstacles”, which described the challenge of alleviating staff concerns about the use of non-surgical casting and recruiting families where there was treatment uncertainty. In order to embed and recruit to the Children’s Radius Acute Fracture Fixation Trial (CRAFFT), staff needed to fit the study within clinical practice, work together, negotiate treatment decisions, and support families. Conclusion. Recruiting families to this RCT was challenging because staff were uncertain about longer-term patient outcomes, and the difficulties were exacerbated by interdisciplinary tensions. Strong family and clinician beliefs, coupled with the complex nature of emergency departments and patient pathways that differed site-by-site, served as barriers to recruitment. Cementing a strong research culture, and exploring families’ treatment preferences, helped to overcome recruitment obstacles. Cite this article: Bone Jt Open 2024;5(4):324–334

Aims. To investigate the impact of consecutive perioperative care transitions on in-hospital recovery of patients who had primary total knee arthroplasty (TKA) over an 11-year period. Methods. This observational cohort study used electronic health record data from all patients undergoing preoperative screening for primary TKA at a Northern Netherlands hospital between 2009 and 2020. In this timeframe, three perioperative care transitions were divided into four periods: Baseline care (Joint Care, n = 171; May 2009 to August 2010), Function-tailored (n = 404; September 2010 to October 2013), Fast-track (n = 721; November 2013 to May 2018), and Prehabilitation (n = 601; June 2018 to December 2020). In-hospital recovery was measured using inpatient recovery of activities (IROA), length of stay (LOS), and discharge to preoperative living situation (PLS). Multivariable regression models were used to analyze the impact of each perioperative care transition on in-hospital recovery. Results. The four periods analyzed involved 1,853 patients (65.9% female (1,221/1,853); mean age 70.1 years (SD 9.0)). IROA improved significantly with each transition: Function-tailored (0.9 days; p < 0.001 (95% confidence interval (CI) -0.32 to -0.15)), Fast-track (0.6 days; p < 0.001 (95% CI -0.25 to -0.16)), and Prehabilitation (0.4 days; p < 0.001 (95% CI -0.18 to -0.10)). LOS decreased significantly in Function-tailored (1.1 days; p = 0.001 (95% CI -0.30 to -0.06)), Fast-track (0.6 days; p < 0.001 (95% CI -0.21 to -0.05)), and Prehabilitation (0.6 days; p < 0.001 (95%CI -0.27 to -0.11)). Discharge to PLS increased in Function-tailored (77%), Fast-track (91.6%), and Prehabilitation (92.6%). Post-hoc analysis indicated a significant increase after the transition to the Fast-track period (p < 0.001 (95% CI 3.19 to 8.00)). Conclusion. This study highlights the positive impact of different perioperative care procedures on in-hospital recovery of patients undergoing primary TKA. Assessing functional recovery, LOS, and discharge towards PLS consistently, provides hospitals with valuable insights into postoperative recovery. This can potentially aid planning and identifying areas for targeted improvements to optimize patient outcomes. Cite this article: Bone Joint J 2024;106-B(6):573–581

Aims. Valgus subsidence of uncemented tibial components following medial unicompartmental knee arthroplasty (UKA) poses a challenge in the early postoperative phase, necessitating a comprehensive understanding of its prevalence, risk factors, and impact on patient outcomes. Methods. This prospective multicentre study analyzed 97 knees from 90 patients undergoing UKA across four participating hospitals. A standardized surgical technique was employed uniformly by all participating surgeons. Postoperative evaluations were conducted preoperatively, and one day, four weeks, three months, and one year postoperative, encompassing weightbearing radiographs, bone mineral density assessments, and clinical outcome reports using the Forgotten Joint Score and Oxford Knee Score. Statistical analyses, including non-parametric correlation analysis using the Kendall correlation coefficient and Mann-Whitney U test, were performed to explore associations between subsidence and various patient-related or radiological parameters. Results. A total of eight patients showed more than 2° valgus subsidence (8.2%), higher than previously reported rates. There were significant correlations between subsidence and higher preoperative varus alignment of the tibia, larger adaptation of the preoperative varus to a postoperative neutral or valgus alignment, mediolateral undersizing of the tibial component, excessive lateral load of tibial component by more lateral position of femoral component relative to tibial component, a lower T-score, and female sex. Our study found no significant difference in pain scores between subsidence and non-subsidence groups at various postoperative milestones. Conclusion. These findings corroborate earlier suggested risk factors based on biomechanical models. Further research might provide the opportunity to identify high-risk groups preoperatively and adapt treatment strategies for these patients. Cite this article: Bone Jt Open 2025;6(2):178–185

Aims. Ilium is the most common site of pelvic Ewing’s sarcoma (ES). Resection of the ilium and iliosacral joint causes pelvic disruption. However, the outcomes of resection and reconstruction are not well described. In this study, we report patients’ outcomes after resection of the ilium and iliosacral ES and reconstruction with a tibial strut allograft. Methods. Medical files of 43 patients with ilium and iliosacral ES who underwent surgical resection and reconstruction with a tibial strut allograft between January 2010 and October 2021 were reviewed. The lesions were classified into four resection zones: I. 1. , I. 2. , I. 3. , and I. 4. , based on the extent of resection. Functional outcomes, oncological outcomes, and surgical complications for each resection zone were of interest. Functional outcomes were assessed using a Musculoskeletal Tumor Society (MSTS) score and Toronto Extremity Salvage Score (TESS). Results. The mean age of the patients was 17 years (SD 9.1). At a mean follow-up of 70.8 months (SD 50), the mean functional outcomes were 24.2 points (SD 6.3) for MSTS and 81 points (SD 11) for TESS. The mean MSTS and TESS scores were associated with the iliac resection zone (< 0.001). Nine patients (20.9%) had local recurrence. The recurrence was not associated with the zone of iliac resection (p = 0.324). The two-year disease-free survival of the patients was 69.4%. The mean time to graft union was longer in patients with the I. 4. resection zone (p < 0.001). The complication rate was 34.9%, and nerve palsy (11.6%) was the most common. The rate of surgical complications was not associated with the resection zone. Conclusion. Reconstruction using tibial strut allograft is an efficient procedure after the resection of the ilium and iliosacral ES. Functional outcomes and complications of iliac ES depend on the resection zone, and inferior outcomes could be generally expected when more segments of the pelvic ring are resected, even if it is reconstructed. Cite this article: Bone Jt Open 2024;5(5):385–393

Aims. Patient dissatisfaction following primary total knee arthroplasty (TKA) with manual jig-based instruments has been reported to be as high as 30%. Robotic-assisted total knee arthroplasty (RA-TKA) has been increasingly used in an effort to improve patient outcomes, however there is a paucity of literature examining patient satisfaction after RA-TKA. This study aims to identify the incidence of patients who were not satisfied following RA-TKA and to determine factors associated with higher levels of dissatisfaction. Methods. This was a retrospective review of 674 patients who underwent primary TKA between October 2016 and September 2020 with a minimum two-year follow-up. A five-point Likert satisfaction score was used to place patients into two groups: Group A were those who were very dissatisfied, dissatisfied, or neutral (Likert score 1 to 3) and Group B were those who were satisfied or very satisfied (Likert score 4 to 5). Patient demographic data, as well as preoperative and postoperative patient-reported outcome measures, were compared between groups. Results. Overall, 45 patients (6.7%) were in Group A and 629 (93.3%) were in Group B. Group A (vs Group B) had a higher proportion of male sex (p = 0.008), preoperative chronic opioid use (p < 0.001), preoperative psychotropic medication use (p = 0.01), prior anterior cruciate ligament (ACL) reconstruction (p < 0.001), and preoperative symptomatic lumbar spine disease (p = 0.004). Group A was also younger (p = 0.023). Multivariate analysis revealed preoperative opioid use (p = 0.012), prior ACL reconstruction (p = 0.038), male sex (p = 0.006), and preoperative psychotropic medication use (p = 0.001) as independent predictive factors of patient dissatisfaction. Conclusion. The use of RA-TKA demonstrated a high rate of patient satisfaction (629 of 674, 93.3%). Demographics for patients not satisfied following RA-TKA included: male sex, chronic opioid use, chronic psychotropic medication use, and prior ACL reconstruction. Patients in these groups should be identified preoperatively and educated on realistic expectations given their comorbid conditions. Cite this article: Bone Jt Open 2024;5(9):758–765

Aims. Patients with A1 and A2 trochanteric hip fractures represent a substantial proportion of trauma caseload, and national guidelines recommend that sliding hip screws (SHS) should be used for these injuries. Despite this, intramedullary nails (IMNs) are routinely implanted in many hospitals, at extra cost and with unproven patient outcome benefit. We have used data from the National Hip Fracture Database (NHFD) to examine the use of SHS and IMN for A1 and A2 hip fractures at a national level, and to define the cost implications of management decisions that run counter to national guidelines. Methods. We used the NHFD to identify all operations for fixation of trochanteric fractures in England and Wales between 1 January 2021 and 31 December 2021. A uniform price band from each of three hip fracture implant manufacturers was used to set cost implications alongside variation in implant use. Results. We identified 18,156 A1 and A2 trochanteric hip fractures in 162 centres. Of these, 13,483 (74.3%) underwent SHS fixation, 2,352 (13.0%) were managed with short IMN, and 2,321 (12.8%) were managed with long IMN. Total cost of IMN added up to £1.89 million in 2021, and the clinical justification for this is unclear since rates of IMN use varied from 0% to 97% in different centres. Conclusion. Most trochanteric hip fractures are managed with SHS, in keeping with national guidelines. There is considerable variance between hospitals for implant choice, despite the lack of evidence for clinical benefit and cost-effectiveness of more expensive nailing systems. This suggests either a lack of awareness of national guidelines or a choice not to follow them. We encourage provider units to reassess their practice if outwith the national norm. Funding bodies should examine implant use closely in this population to prevent resource waste at a time of considerable health austerity. Cite this article: Bone Jt Open 2022;3(10):741–745

Aims. Gram-negative infections are associated with comorbid patients, but outcomes are less well understood. This study reviewed diagnosis, management, and treatment for a cohort treated in a tertiary spinal centre. Methods. A retrospective review was performed of all gram-negative spinal infections (n = 32; median age 71 years; interquartile range 60 to 78), excluding surgical site infections, at a single centre between 2015 to 2020 with two- to six-year follow-up. Information regarding organism identification, antibiotic regime, and treatment outcomes (including clinical, radiological, and biochemical) were collected from clinical notes. Results. All patients had comorbidities and/or non-spinal procedures within the previous year. Most infections affected lumbar segments (20/32), with Escherichia coli the commonest organism (17/32). Causative organisms were identified by blood culture (23/32), biopsy/aspiration (7/32), or intraoperative samples (2/32). There were 56 different antibiotic regimes, with oral (PO) ciprofloxacin being the most prevalent (13/56; 17.6%). Multilevel, contiguous infections were common (8/32; 25%), usually resulting in bone destruction and collapse. Epidural collections were seen in 13/32 (40.6%). In total, five patients required surgery, three for neurological deterioration. Overall, 24 patients improved or recovered with a mean halving of CRP at 8.5 days (SD 6). At the time of review (two to six years post-diagnosis), 16 patients (50%) were deceased. Conclusion. This is the largest published cohort of gram-negative spinal infections. In older patients with comorbidities and/or previous interventions in the last year, a high level of suspicion must be given to gram-negative infection with blood cultures and biopsy essential. Early organism identification permits targeted treatment and good initial clinical outcomes; however, mortality is 50% in this cohort at a mean of 4.2 years (2 to 6) after diagnosis. Cite this article: Bone Jt Open 2024;5(5):435–443

Aims. The mid-term results of kinematic alignment (KA) for total knee arthroplasty (TKA) using image derived instrumentation (IDI) have not been reported in detail, and questions remain regarding ligamentous stability and revisions. This paper aims to address the following: 1) what is the distribution of alignment of KA TKAs using IDI; 2) is a TKA alignment category associated with increased risk of failure or poor patient outcomes; 3) does extending limb alignment lead to changes in soft-tissue laxity; and 4) what is the five-year survivorship and outcomes of KA TKA using IDI?. Methods. A prospective, multicentre, trial enrolled 100 patients undergoing KA TKA using IDI, with follow-up to five years. Alignment measures were conducted pre- and postoperatively to assess constitutional alignment and final implant position. Patient-reported outcome measures (PROMs) of pain and function were also included. The Australian Orthopaedic Association National Joint Arthroplasty Registry was used to assess survivorship. Results. The postoperative HKA distribution varied from 9° varus to 11° valgus. All PROMs showed statistical improvements at one year (p < 0.001), with further improvements at five years for Knee Osteoarthritis Outcome Score symptoms (p = 0.041) and Forgotten Joint Score (p = 0.011). Correlation analysis showed no difference (p = 0.610) between the hip-knee-ankle and joint line congruence angle at one and five years. Sub-group analysis showed no difference in PROMs for patients placed within 3° of neutral compared to those placed > 3°. There were no revisions for tibial loosening; however, there were reports of a higher incidence of poor patella tracking and patellofemoral stiffness. Conclusion. PROMs were not impacted by postoperative alignment category. Ligamentous stability was maintained at five years with joint line obliquity. There were no revisions for tibial loosening despite a significant portion of tibiae placed in varus; however, KA executed with IDI resulted in a higher than anticipated rate of patella complications. Cite this article: Bone Jt Open 2022;3(8):656–665

Aims. This study assessed the impact of COVID-19 on hip and distal femur fracture patient outcomes across three successive UK lockdown periods over one year. Methods. A single-centre retrospective cohort study was performed at an acute NHS Trust. Hip and distal femur fracture patients admitted within the first month from each of the three starting dates of each national lockdown were included and compared to a control group in March 2019. Data were collected as per the best practice tariff outcomes including additional outcomes as required. Data collection included COVID-19 status, time to theatre, 30-day mortality, presence of acute kidney injury (AKI) and pneumonia, and do not attempt cardiopulmonary resuscitation (DNACPR) status. Data were analyzed using an independent-samples t-test or chi-squared test with Fisher’s exact test where applicable. A p-value of < 0.05 was considered statistically significant. Results. A total of 95 patients during the pandemic were included and 20 were COVID-positive. Patients experienced a statistically significant increase in time to theatre in Lockdown 1 compared to 2019 (p = 0.039) with a decrease with successive lockdown periods by Lockdown 3. The 30-day mortality increased from 8.8% in 2019 to 10.0% to 14.8% in all lockdown periods. COVID-positive patient mortality was 30.0% (p = 0.063, odds ratio (OR) = 4.43 vs 2019). The rates of AKI and pneumonia experienced were higher for patients during the pandemic. The highest rates were experienced in COVID-positive patients, with 45.0% of patients with AKI versus 27.0% in 2019 (p = 0.38, OR = 1.80), and 50.0% of patients diagnosed with pneumonia versus 16.2% in 2019 (p = 0.0012, OR = 5.17). The percentage of patients with a DNACPR increased from 30.0% in 2019 to 60.7% by Lockdown 3 (p = 0.034, OR = 3.61). Conclusion. COVID-positive hip and distal femur fracture patients are at a higher risk of mortality due to AKI and pneumonia. Patient outcomes have improved with successive lockdowns to pre-pandemic levels. Cite this article: Bone Jt Open 2021;2(12):1017–1026

Aims. This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Methods. Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement. Results. A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months. Conclusion. Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III. Cite this article: Bone Jt Open 2022;3(4):291–301