➢ Despite substantial health-care spending, both the U.S. and U.K. lack standardized, operational definitions of value in specialty care, limiting their ability to optimize patient-centric health outcomes and appropriate selection and utilization of resources. ➢ First-generation value-based specialty care models in the U.S., like the Bundled Payments for Care Improvement Initiative and Comprehensive Care for Joint Replacement, have achieved modest savings by focusing on post-acute care and procedural efficiency, without negatively impacting quality metrics. Similarly, the Getting It Right First Time initiative in the U.K. aimed to bring about higher-quality care in hospitals, at lower cost, by reducing unwanted variations in services and practices. However, there remains no true understanding of impact on value, of efficacy based on measurement of patient-centric health outcomes that matter to patients, or of whether interventions were appropriately selected in the first place. ➢ A standardized value metric, specifically the incremental cost-effectiveness ratio (ICER), is critical to measuring quality in specialty care, enabling health-care systems to compare treatment options on the basis of both cost and patient-centric outcomes. ➢ The ICER integrates quality-adjusted life years, cost data, and the duration of effectiveness, providing a framework for shared decision-making, care variation reduction, and more strategic site-of-service decisions. ➢ Health-care systems and policymakers should adopt ICER-based frameworks to transition from volume-based incentives to value-based models that support innovation, accountability, and whole-person musculoskeletal specialty care.

➢ Despite substantial health-care spending, both the U.S. and U.K. lack standardized, operational definitions of value in specialty care, limiting their ability to optimize patient-centric health outcomes and appropriate selection and utilization of resources. ➢ First-generation value-based specialty care models in the U.S., like the Bundled Payments for Care Improvement Initiative and Comprehensive Care for Joint Replacement, have achieved modest savings by focusing on post-acute care and procedural efficiency, without negatively impacting quality metrics. Similarly, the Getting It Right First Time initiative in the U.K. aimed to bring about higher-quality care in hospitals, at lower cost, by reducing unwanted variations in services and practices. However, there remains no true understanding of impact on value, of efficacy based on measurement of patient-centric health outcomes that matter to patients, or of whether interventions were appropriately selected in the first place. ➢ A standardized value metric, specifically the incremental cost-effectiveness ratio (ICER), is critical to measuring quality in specialty care, enabling health-care systems to compare treatment options on the basis of both cost and patient-centric outcomes. ➢ The ICER integrates quality-adjusted life years, cost data, and the duration of effectiveness, providing a framework for shared decision-making, care variation reduction, and more strategic site-of-service decisions. ➢ Health-care systems and policymakers should adopt ICER-based frameworks to transition from volume-based incentives to value-based models that support innovation, accountability, and whole-person musculoskeletal specialty care.

Anterior cruciate ligament (ACL) injuries are common and often require surgical reconstruction. Autografts remain the clinical standard for ACL reconstruction (ACLR) but are limited by donor site morbidity, inconsistent outcomes, and supply constraints. Here, we report the development of electrospun ligament (ES-Lig), a fully degradable, electrospun scaffold composed of poly(ε-caprolactone) (PCL) designed to mimic the extracellular matrix (ECM) of the native ACL. A scalable manufacturing process was established, incorporating electrospinning, filament stretching, alignment, and braiding. ES-Lig demonstrated controlled in vitro degradation over 12 months while retaining sufficient mechanical strength for early-stage healing. Mechanical characterisation revealed tensile properties and fixation stability comparable to autografts. In vitro biocompatibility was confirmed through cytotoxicity assays, patient-derived ACL explants, and direct cell growth onto the material. In an ovine ACLR model, ES-Lig enabled functional recovery, tissue infiltration throughout its length, and joint stability within 10 weeks post-implantation. Histological and imaging analyses confirmed graft-bone integration, vascularisation, and early ligamentisation. These findings establish ES-Lig as a promising, clinically translatable scaffold for next-generation ACL repair.

As DNA variants accumulate in somatic stem cells, become selected or evolve neutrally, they may ultimately alter tissue function. When, and how, selection occurs in homeostatic tissues is incompletely understood. Here, we introduce SCIFER, a scalable method that identifies selection in an individual tissue, without requiring knowledge of the driver event. SCIFER also infers self-renewal and mutation dynamics of the tissue's stem cells, and the size and age of selected clones. Probing bulk whole-genome sequencing data of nonmalignant human bone marrow and brain, we detected pervasive selection in both tissues. Selected clones in hematopoiesis, with or without known drivers, were initiated uniformly across life. In the brain, we found pre-malignant clones with glioma-initiating mutations and clones without known drivers. In contrast to hematopoiesis, selected clones in the brain originated preferentially from childhood to young adulthood. SCIFER is broadly applicable to renewing somatic tissues to detect and quantify selection.

Rotator cuff repair has a substantial failure rate despite various attempts to improve outcome and prevent a retear. Patch augmentation is an intuitively appealing approach to seek to reduce failure rate and improve outcomes for patients. Two main augmentation approaches are used: "on-lay" and "bridging." The literature is heterogeneous, and the best approach is uncertain. The evidence on patch augmentation for rotator cuff repair is both disparate and weak. Large randomized trials and registry data are required to move the field, ensure patient safety, and avoid wasting precious resources.

Advanced robotic systems that replicate musculoskeletal structure and function have significant potential for a wide range of applications. Although they are proposed to be better platforms for biomedical applications, little is known about how well current musculoskeletal humanoid systems mimic the motion and force profiles of humans. This is particularly relevant to the field of tendon tissue engineering, where engineered grafts require advanced bioreactor systems that accurately replicate the kinetic and kinematic profiles experienced by the humans in vivo . A motion study was conducted comparing the kinetic and kinematic profiles produced by a musculoskeletal humanoid robot shoulder to a group of human participants completing abduction/adduction tasks. Results from the study indicate that the humanoid arm can be programed to either replicate the kinematic profile or the kinetic profile of human participants during task completion, but not both simultaneously. This study supports the use of humanoid robots for applications such as tissue engineering and highlights suggestions to further enhance the physiologic relevance of musculoskeletal humanoid robotic platforms. ### Competing Interest Statement The authors have declared no competing interest.

Tendinopathy can commonly occur around the foot and ankle resulting in isolated rupture, debilitating pain and degenerative foot deformity. The pathophysiology and key cells involved are not fully understood. This is partly because the dense collagen matrix that surrounds relatively few resident cells limits the ability of previous techniques to identify and target those cells of interest. In this study, we apply novel single cell RNA sequencing (CITE-Seq) techniques to healthy and tendinopathic foot/ankle tendons. For the first time we have identified multiple sub-populations of cells in human tendons. These findings challenge the view that there is a single principal tendon cell type and open new avenues for further study. Healthy tendon samples were obtained from patients undergoing tendon transfer procedures; including tibialis posterior and FHL. Diseased tendon samples were obtained during debridement of intractable Achilles and peroneal tendinopathy, and during fusion of degenerative joints. Single cell RNA sequencing with surface proteomic analysis identified 10 sub-populations of human tendon derived cells. These included groups expressing genes associated with fibro-adipogenic progenitors (FAPs) as well as ITGA7+VCAM1- recently described in mouse muscle but, as yet, not human tendon. In addition we have identified previously unrecognised sub-classes of collagen type 1 associated tendon cells. Each sub-class expresses a different set of extra-cellular matrix genes suggesting they each play a unique role in maintaining the structural integrity of normal tendon. Diseased tendon harboured a greater proportion of macrophages and cytotoxic lymphocytes than healthy tendon. This inflammatory response is potentially driven by resident tendon fibroblasts which show increased expression of pro-inflammatory cytokines. Finally, identification of a previously unknown sub-population of cells found predominantly in tendinopathic tissue offers new insight into the underlying pathophysiology. Further work aims to identify novel proteins targets for possible therapeutic pathways.

Frozen shoulder is a spontaneously self-resolving chronic inflammatory fibrotic human disease, which distinguishes the condition from most fibrotic diseases that are progressive and irreversible. Using single-cell analysis, we identify pro-inflammatory MERTK low CD48 + macrophages and MERTK + LYVE1 + MRC1+ macrophages enriched for negative regulators of inflammation which co-exist in frozen shoulder capsule tissues. Micro-cultures of patient-derived cells identify integrin-mediated cell-matrix interactions between MERTK+ macrophages and pro-resolving DKK3+ and POSTN+ fibroblasts, suggesting that matrix remodelling plays a role in frozen shoulder resolution. Cross-tissue analysis reveals a shared gene expression cassette between shoulder capsule MERTK+ macrophages and a respective population enriched in synovial tissues of rheumatoid arthritis patients in disease remission, supporting the concept that MERTK+ macrophages mediate resolution of inflammation and fibrosis. Single-cell transcriptomic profiling and spatial analysis of human foetal shoulder tissues identify MERTK + LYVE1 + MRC1+ macrophages and DKK3+ and POSTN+ fibroblast populations analogous to those in frozen shoulder, suggesting that the template to resolve fibrosis is established during shoulder development. Crosstalk between MerTK+ macrophages and pro-resolving DKK3+ and POSTN+ fibroblasts could facilitate resolution of frozen shoulder, providing a basis for potential therapeutic resolution of persistent fibrotic diseases.

Background Anterior cruciate ligament injury of the knee is common and leads to decreased activity and risk of secondary osteoarthritis of the knee. Management of patients with a non-acute anterior cruciate ligament injury can be non-surgical (rehabilitation) or surgical (reconstruction). However, insufficient evidence exists to guide treatment. Objective(s) To determine in patients with non-acute anterior cruciate ligament injury and symptoms of instability whether a strategy of surgical management (reconstruction) without prior rehabilitation was more clinically and cost-effective than non-surgical management (rehabilitation). Design A pragmatic, multicentre, superiority, randomised controlled trial with two-arm parallel groups and 1:1 allocation. Due to the nature of the interventions, no blinding could be carried out. Setting Twenty-nine NHS orthopaedic units in the United Kingdom. Participants Participants with a symptomatic (instability) non-acute anterior cruciate ligament-injured knee. Interventions Patients in the surgical management arm underwent surgical anterior cruciate ligament reconstruction as soon as possible and without any further rehabilitation. Patients in the rehabilitation arm attended physiotherapy sessions and only were listed for reconstructive surgery on continued instability following rehabilitation. Surgery following initial rehabilitation was an expected outcome for many patients and within protocol. Main outcome measures The primary outcome was the Knee Injury and Osteoarthritis Outcome Score 4 at 18 months post randomisation. Secondary outcomes included return to sport/activity, intervention-related complications, patient satisfaction, expectations of activity, generic health quality of life, knee-specific quality of life and resource usage. Results Three hundred and sixteen participants were recruited between February 2017 and April 2020 with 156 randomised to surgical management and 160 to rehabilitation. Forty-one per cent ( n = 65) of those allocated to rehabilitation underwent subsequent reconstruction within 18 months with 38% ( n = 61) completing rehabilitation and not undergoing surgery. Seventy-two per cent ( n = 113) of those allocated to surgery underwent reconstruction within 18 months. Follow-up at the primary outcome time point was 78% ( n = 248; surgical, n = 128; rehabilitation, n = 120). Both groups improved over time. Adjusted mean Knee Injury and Osteoarthritis Outcome Score 4 scores at 18 months had increased to 73.0 in the surgical arm and to 64.6 in the rehabilitation arm. The adjusted mean difference was 7.9 (95% confidence interval 2.5 to 13.2; p = 0.005) in favour of surgical management. The per-protocol analyses supported the intention-to-treat results, with all treatment effects favouring surgical management at a level reaching statistical significance. There was a significant difference in Tegner Activity Score at 18 months. Sixty-eight per cent ( n = 65) of surgery patients did not reach their expected activity level compared to 73% ( n = 63) in the rehabilitation arm. There were no differences between groups in surgical complications ( n = 1 surgery, n = 2 rehab) or clinical events ( n = 11 surgery, n = 12 rehab). Of surgery patients, 82.9% were satisfied compared to 68.1% of rehabilitation patients. Health economic analysis found that surgical management led to improved health-related quality of life compared to non-surgical management (0.052 quality-adjusted life-years, p = 0.177), but with higher NHS healthcare costs (£1107, p < 0.001). The incremental cost-effectiveness ratio for the surgical management programme versus rehabilitation was £19,346 per quality-adjusted life-year gained. Using £20,000–30,000 per quality-adjusted life-year thresholds, surgical management is cost-effective in the UK setting with a probability of being the most cost-effective option at 51% and 72%, respectively. Limitations Not all surgical patients underwent reconstruction, but this did not affect trial interpretation. The adherence to physiotherapy was patchy, but the trial was designed as pragmatic. Conclusions Surgical management (reconstruction) for non-acute anterior cruciate ligament-injured patients was superior to non-surgical management (rehabilitation). Although physiotherapy can still provide benefit, later-presenting non-acute anterior cruciate ligament-injured patients benefit more from surgical reconstruction without delaying for a prior period of rehabilitation. Future work Confirmatory studies and those to explore the influence of fidelity and compliance will be useful. Trial registration This trial is registered as Current Controlled Trials ISRCTN10110685; ClinicalTrials.gov Identifier: NCT02980367. Funding This award was funded by the National Institute of Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 14/140/63) and is published in full in Health Technology Assessment ; Vol. 28, No. 27. See the NIHR Funding and Awards website for further award information.

BACKGROUND:Unicompartmental knee replacement (UKR) is an effective treatment for end-stage medial compartment osteoarthritis, but there can be problems with fixation. The cementless UKR was introduced to address this issue. It is unknown how its functional outcomes compare with those of the cemented version on a national scale. We performed a matched comparison of the clinical and functional outcomes of cementless and cemented UKRs. METHODS:Using the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR), 14,764 Oxford UKRs with linked data regarding patient-reported outcomes were identified. A total of 6,906 UKRs (3,453 cemented and 3,453 cementless) were propensity score matched on the basis of patient, surgical, and implant factors. RESULTS:The 10-year cumulative implant survival rate was 93.0% (95% confidence interval [CI], 90.0% to 95.1%) for cementless UKRs and 91.3% (95% CI, 89.0% to 93.0%) for cemented UKRs. The cementless UKR group had a significantly lower revision risk (hazard ratio [HR], 0.74; p = 0.02). Subgroup analyses showed a stronger effect size (HR, 0.66) among UKRs performed by high-caseload surgeons (i.e., surgeons performing ≥30 UKRs/year). In the overall cohort, the postoperative Oxford Knee Score (OKS) in the cementless group (mean and standard deviation, 39.1 ± 8.7) was significantly higher (p = 0.001) than that in the cemented group (38.5 ± 8.6). The cementless group gained a mean of 17.6 ± 9.3 points in the OKS postoperatively and the cemented group gained 16.5 ± 9.6 points, with a difference of 1.1 points between the groups (p < 0.001). The difference in OKS points gained postoperatively was highest among UKRs performed by high-caseload surgeons, with the cementless group gaining 1.8 points more (p < 0.001) than the cemented group. CONCLUSIONS:The cementless UKR demonstrated better 10-year implant survival and postoperative functional outcomes than the cemented UKR. The difference was largest among UKRs performed by high-caseload surgeons, with the cementless fixation group having an HR for revision of 0.66 and an approximately 2-point greater improvement in the OKS compared with the cemented fixation group. LEVEL OF EVIDENCE:Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Many surgical tendon repairs fail despite advances in surgical materials and techniques. Tendon repair failure can be partially attributed to the tendon's poor intrinsic healing capacity and the repurposing of sutures from other clinical applications. Electrospun materials show promise as a biological scaffold to support endogenous tendon repair, but their relatively low tensile strength has limited their clinical translation. It is hypothesized that combining electrospun fibers with a material with increased tensile strength may improve the suture's mechanical properties while retaining biophysical cues necessary to encourage cell-mediated repair. This article describes the production of a hybrid electrospun-extruded suture with a sheath of submicron electrospun fibers and a core of melt-extruded fibers. The porosity and tensile strength of this hybrid suture is compared with an electrospun-only braided suture and clinically used sutures Vicryl and polydioxanone (PDS). Bioactivity is assessed by measuring the adsorbed serum proteins on electrospun and melt-extruded filaments using mass spectrometry. Human hamstring tendon fibroblast attachment and proliferation were quantified and compared between the hybrid and control sutures. Combining an electrospun sheath with melt-extruded cores created a hybrid braid with increased tensile strength (70.1 ± 0.3N) compared with an electrospun only suture (12.9 ± 1 N, p < 0.0001). The hybrid suture had a similar force at break to clinical sutures, but lower stiffness and stress. The Young's modulus was 772.6 ± 32 MPa for the hybrid suture, 1693.0 ± 69 MPa for PDS, and 3838.0 ± 132 MPa for Vicryl, p < 0.0001. Hybrid sutures had lower overall porosity than electrospun-only sutures (40 ± 4% and 60 ± 7%, respectively, p = 0.0018) but had a significantly larger overall porosity and average pore diameter compared with surgical sutures. There were similar clusters of adsorbed proteins on electrospun and melt-extruded filaments, which were distinct from PDS. Tendon fibroblast attachment and cell proliferation on hybrid and electrospun sutures were significantly higher than on clinical sutures. This study demonstrated that a bioactive suture with increased tensile strength and lower stiffness could be produced by adding a core of 10 μm melt-extruded fibers to a sheath of electrospun fibers. In contrast to currently used sutures, the hybrid sutures promoted a bioactive response: serum proteins adsorbed, and fibroblasts attached, survived, grew along the sutures, and adopted appropriate morphologies.

Clonal hematopoiesis (CH) arises when hematopoietic stem cells (HSCs) acquire mutations, most frequently in the DNMT3A and TET2 genes, conferring a competitive advantage through mechanisms that remain unclear. To gain insight into how CH mutations enable gradual clonal expansion, we used single-cell multi-omics with high-fidelity genotyping on human CH bone marrow (BM) samples. Most of the selective advantage of mutant cells occurs within HSCs. DNMT3A- and TET2-mutant clones expand further in early progenitors, while TET2 mutations accelerate myeloid maturation in a dose-dependent manner. Unexpectedly, both mutant and non-mutant HSCs from CH samples are enriched for inflammatory and aging transcriptomic signatures, compared with HSCs from non-CH samples, revealing a non-cell-autonomous effect. However, DNMT3A- and TET2-mutant HSCs have an attenuated inflammatory response relative to wild-type HSCs within the same sample. Our data support a model whereby CH clones are gradually selected because they are resistant to the deleterious impact of inflammation and aging.

Background/Aims Intra-articular corticosteroid injections (IACI) are recommended in the UK by NICE as an adjunctive treatment for uncontrolled pain from osteoarthritis (OA). NICE guidance states there is no evidence for therapeutic benefit lasting beyond three months, and that more evidence is needed on effectiveness at non-knee joints. We therefore aimed to assess the longer-term effect of IACI use on pain medication prescriptions among people with hand, hip, knee or shoulder OA. Methods We conducted a cohort study using UK primary care (CPRD GOLD) data for patients aged >= 20 years with a first diagnosis of OA during 2005-2019, excluding those with prior orthopaedic surgery referral or OA diagnosed at multiple joints. Exposure to IACI was defined using Read codes. The primary outcome was incident prescribing of pain medication: oral non-steroidal anti-inflammatory drugs (NSAIDs), opioids, oral corticosteroids, paracetamol, partial opioids, and topical NSAIDs. In main analyses, an instrumental variable (IV) approach was used. Index date was six months after OA diagnosis date and IV was defined as practice preference for IACI use in the year prior to index date (single and recurrent use considered separately). Outcomes were measured over five years from index date. Covariate balance was assessed, and two-step Poisson regression used where assumptions met. In secondary analyses, propensity score (PS) matching was carried out and time-varying exposure Cox models used to estimate treatment effect. Results Of 181,818 eligible patients, 92,157 (50.7%) were retained in IV analyses of single IACI and 89,103 (49.0%) of repeat IACI. Covariates were well balanced (SMD <= 0.1) across IV groups for hand (single IACI only) and knee OA, but not hip or shoulder OA. In IV analyses of hand OA, single IACI was associated with lower 5-year cumulative incidence of several pain medications including oral corticosteroids (relative risk [RR] 0.27 [95% CI 0.10, 0.76], paracetamol (RR 0.27 [0.09, 0.78] and partial opioids (RR 0.24 [0.10, 0.60]). IACI for knee OA was associated with lower 5-year cumulative incidence of most pain medications, e.g., for partial opioids a RR 0.46 [95% CI 0.34, 0.61] and RR 0.33 [0.21, 0.51] for single and recurrent IACI, respectively. Most PS matched analyses had >20,000 included patients (all joints combined), with covariates well balanced across IACI exposure status. PS matching confirmed a reduction in incidence of several pain medications associated with single IACI, e.g., lower incidence of partial opioids following IACI for any of hand, hip, knee or shoulder OA. Conclusion Our main findings suggest IACI use for hand or knee OA may reduce subsequent need for analgesics. Among knee OA patients, generally larger reductions were observed following recurrent than single IACI. In secondary analyses, single IACI for hand, hip, knee or shoulder OA was associated with lower subsequent use of partial opioids. Disclosure S. Hawley: None. A. Prats-Uribe: Grants/research support; European Medicines Agency. G. Matharu: Grants/research support; National Institute of Health and Care Research, Academy of Medical Sciences. A. Delmestri: None. D. Prieto-Alhambra: Consultancies; AstraZeneca, UCB Biopharma. Grants/research support; European Medicines Agency, Innovative Medicines Initiative, Amgen, Chiesi-Taylor, Lilly, Janssen, Novartis, UCB Biopharma. Other; Amgen, Astrellas, Janssen, Synapse Management Partners, UCB Biopharma. A. Judge: Grants/research support; National Institute of Health and Care Research, Health Data Research UK, Versus Arthritis, Healthcare Quality Improvement Partnership (HQIP), Royal College of Physicians (RCP), Tommy's, The Health Foundation. M. Whitehouse: Royalties; Taylor Francis. Member of speakers' bureau; Heraeus. Grants/research support; National Institute of Health and Care Research, Healthcare Quality Improvement Partnership (HQIP), Ceramtec.

Objectives: Surgical scaffolds are used to augment rotator cuff tendon repairs. Interactions between recruited immune cells and tendon-resident stromal cells influence whether the scaffold is integrated or rejected by the body. The primary aim of this in vitro study was to compare the inflammatory response of human monocytes to different surgical scaffolds. The secondary aim was to determine how this monocyte response affects the behavior of human rotator cuff tendon-derived stromal cells in vitro. Methods: Primary human monocytes were cultured on four commercially available scaffolds: LARS ligament (synthetic); GraftJacket (allograft), Permacol (xenograft, cross-linked), and Conexa (xenograft, noncross-linked). Secreted inflammatory proteins were measured after 1 and 10 days. Foreign body giant cell formation was assessed after 10 days. Proliferation and gene expression of tendon stromal cells were assessed after being grown in a conditioned medium from monocyte-scaffold cultures. Results: After 10 days, monocytes cultured on the Conexa scaffold secreted the highest levels of the pro-inflammatory markers GM-CSF, IL-8, and IL-10 (fig. 1). After 1 day, tendon stromal cells incubated in conditioned media from Conexa-monocyte cultures expressed lower Collagen Type VI and increased MMP3 and MMP6 mRNA (fig. 2). Foreign Body Giant Cell formation was most prominent in monocytes cultured on the Permacol scaffold (Figure 3). Conclusions: In vitro experiments demonstrated that xenograft scaffolds elicited a more pronounced pro-inflammatory response in human monocytes compared to synthetic and allograft scaffolds. Inflammatory cytokines secreted by monocytes in response to xenografts may modulate scaffold integration through paracrine signaling to tendon stromal cells. These findings may help explain the clinical performance of xenograft scaffolds for tendon repair and inform future scaffold design.

Aims:This study evaluates the association between consultant and hospital volume and the risk of re-revision and 90-day mortality following first-time revision of primary hip arthroplasty for aseptic loosening. Methods:We conducted a cohort study of first-time, single-stage revision hip arthroplasties (RHAs) performed for aseptic loosening and recorded in the National Joint Registry (NJR) data for England, Wales, Northern Ireland, and the Isle of Man between 2003 and 2019. Patient identifiers were used to link records to national mortality data, and to NJR data to identify subsequent re-revision procedures. Multivariable Cox proportional hazard models with restricted cubic splines were used to define associations between volume and outcome. Results:Among 12,961 RHAs there were 513 re-revisions within two years, and 95 deaths within 90 days of surgery. The risk of re-revision was highest for a consultant's first RHA (hazard ratio (HR) 1.56 (95% CI 1.15 to 2.12)) and remained significantly elevated for their first 24 cases (HR 1.26 (95% CI 1.00 to 1.58)). Annual consultant volumes of five/year were associated with an almost 30% greater risk of re-revision (HR 1.28 (95% CI 1.00 to 1.64)) and 80% greater risk of 90-day mortality (HR 1.81 (95% CI 1.02 to 3.21)) compared to volumes of 20/year. RHAs performed at hospitals which had cumulatively undertaken fewer than 167 RHAs were at up to 70% greater risk of re-revision (HR 1.70 (95% CI 1.12 to 2.59)), and those having undertaken fewer than 307 RHAs were at up to three times greater risk of 90-day mortality (HR 3.05 (95% CI 1.19 to 7.82)). Conclusion:This study found a significantly higher risk of re-revision and early postoperative mortality following first-time single-stage RHA for aseptic loosening when performed by lower-volume consultants and at lower-volume institutions, supporting the move towards the centralization of such cases towards higher-volume units and surgeons.

IntroductionHand osteoarthritis is more common in women, and its risk increases around the time of the menopause. We set out to describe the timing between menopause and the onset of symptomatic hand osteoarthritis (OA), and associations with the use of hormone replacement therapy (HRT) or its discontinuation, describing any identifiable subgroups of women.MethodsRetrospective healthcare-records study of sequential women referred to a specialist hand OA clinic, 2007–2015. Confirmation of hand OA diagnosis was by clinican, by accepted criteria. Demographics and clinical variables were from healthcare-records, recorded by standardised proforma. Outcomes of interest were reported age of onset of hand symptoms, reported age at final menstrual period (FMP), time from FMP to reported onset of hand symptoms and time from cessation of HRT to reported onset of hand symptoms. Exposure categories for systemic HRT use were never users, current users, previous users. Analysis of Variance compared groups; linear regression analysed associations of exposure with outcome.Results82/92(89%) of eligible women were post-menopausal, mean age at FMP 49.9 years (SD5.4). In these post-menopausal women, median time from FMP to hand symptom onset was 3 years. 48/82 (59%) developed hand symptoms within the defined peri-menopausal period (FMP ± 4 years), whilst some women developed their symptoms before or after (range −25, 30 years). In women who discontinued HRT prior to symptom onset, the median time from HRT cessation to onset of hand symptoms was 6 months. Past HRT users were older at hand symptom onset than women who had not taken HRT [coeff.4.7 years (0.92, 8.39); P = 0.015].ConclusionsThis study adds to evidence associating the menopause/sex hormone deficiency with hand OA symptom onset in a sizeable subgroup of women (but not all). HRT use/cessation appears to influence the timing of onset of hand OA symptoms. It is not possible to interpret from this type of study whether sex hormone deficiency is causative of disease or modulates its symptoms. It is also not possible to judge whether painful hand osteoarthritis in post-menopausal women is a subtype of disease. Further investigation is indicated of sex-specific subtypes and potential for personalised medicine for post-menopausal women with hand osteoarthritis, as a clearly definable high-risk subgroup.

BackgroundPeriprosthetic fractures are rare but serious complications of unicompartmental knee arthroplasty (UKA). Although cementless UKA has a lower risk of loosening than cemented, there are concerns that tibial fracture risk may be higher given the reliance on interference fit for primary stability. The risk of fracture and the effect of surgical fixation are currently unknown. We compared the periprosthetic fracture rate following cemented and cementless UKA surgery.MethodsA total of 14,122 medial mobile-bearing UKAs (7,061 cemented and 7,061 cementless) from the National Joint Registry and Hospital Episodes Statistics database were propensity score-matched. Cumulative fracture rates were calculated and Cox regressions were used to compare fixation groups.ResultsThe three-month periprosthetic fracture rates were similar (P = .80), being 0.10% in the cemented group and 0.11% in the cementless group. The fracture rates were highest during the first three months postoperatively, but then decreased and remained constant between one and 10 years after surgery. The one-year cumulative fracture rates were 0.2% (confidence interval [CI]: 0.1 to 0.3) for cemented and 0.2% (CI: 0.1 to 0.3) for cementless cases. The 10-year cumulative fracture rates were 0.8% (CI: 0.2 to 1.3) and 0.8% (CI: 0.3 to 1.3), respectively. The hazard ratio during the whole study period was 1.06 (CI: 0.64 to 1.77; P = .79).ConclusionsThe periprosthetic fracture rate following mobile bearing UKA surgery is low, being about 1% at 10 years. There were no significant differences in fracture rates between cemented and cementless implants after matching. We surmise that surgeons are aware of the higher theoretical risk of early fracture with cementless components and take care with tibial preparation.Levels of evidenceIII.

Objective To assess the impact of local commissioners’ policies for body mass index on access to knee replacement surgery in England. Methods A Natural Experimental Study using interrupted time series and difference-in-differences analysis. We used National Joint Registry for England data linked to the 2015 Index of Multiple Deprivation for 481,555 patients who had primary knee replacement surgery in England between January 2009 and December 2019. Clinical Commissioning Group policies introduced before June 2018 to alter access to knee replacement for patients who were overweight or obese were considered the intervention. The main outcome measures were rate per 100,000 of primary knee replacement surgery and patient demographics (body mass index, Index of Multiple Deprivation, independently-funded surgery) over time. Results Rates of surgery had a sustained fall after the introduction of a policy (trend change of -0.98 operations per 100,000 population aged 40+, 95% confidence interval -1.22 to -0.74, P<0.001), whereas rates increased in localities with no policy introduction. At three years after introduction, there were 10.5 per 100,000 population fewer operations per quarter aged 40+ compared to the counterfactual, representing a fall of 14.1% from the rate expected had there been no change in trend. There was no dose response effect with policy severity. Rates of surgery fell in all patient groups, including non-obese patients following policy introduction. The proportion of independently-funded operations increased after policy introduction, as did the measure of socioeconomic deprivation of patients. Conclusions Body mass index policy introduction was associated with decreases in the rates of knee replacement surgery across localities that introduced policies. This affected all patient groups, not just obese patients at whom the policies were targeted. Changes in patient demographics seen after policy introduction suggest these policies may increase health inequalities and further qualitative research is needed to understand their implementation and impact.

Objectives: To identify risk factors of postoperative delirium among hip fracture patients with normal preoperative cognition, and examine associations with returning home or recovery of mobility. Design: Prospective cohort study.Setting and Participants: We used the National Hip Fracture Database (NHFD) to identify patients presenting with hip fracture in England (2018-2019), but excluded those with abnormal cognition [abbreviated mental test score (AMTS) < 8] on presentation. Methods: We examined the results of routine delirium screening performed using the 4 A's Test (4AT), to assess alertness, attention, acute change, and orientation in a 4-item mental test. Associations between 4AT score and return home or to outdoor mobility at 120 days were estimated, and risk factors identified for abnormal 4AT scores: (1) 4AT >= 4 suggesting delirium and (2) 4AT = 1-3 being an intermediate score not excluding delirium.Results: Overall, 63,502 patients (63%) had a preoperative AMTS >= 8, in whom a postoperative 4AT score >= 4 suggestive of delirium was seen in 4454 (7%). These patients were less likely to return home [odds ratio (OR), 0.46; 95% CI, 0.38-0.55] or regain outdoor mobility (OR, 0.63; 95% CI, 0.53-0.75) by 120 days. Multiple factors including any deficit in preoperative AMTS and malnutrition were associated with higher risk of 4AT >= 4, while use of preoperative nerve blocks was associated with lower risk (OR, 0.88; 95% CI, 0.81-0.95). Poorer outcomes were also seen in 12,042 (19%) patients with 4AT = 1-3; additional risk factors associated with this score included socioeconomic deprivation and surgical procedure types that were not compliant with National Institute of Health and Care Excellence guidance.Conclusion and Implications: Delirium after hip fracture surgery significantly reduces the likelihood of returning home or to outdoor mobility. Our findings underline the importance of measures to prevent postoperative delirium, and aid the identification of high-risk patients for whom delirium prevention might potentially improve outcomes.(c) 2023 AMDA - The Society for Post-Acute and Long-Term Care Medicine.