Effects of recurrent intra-articular corticosteroid injections for osteoarthritis at 3 months and beyond: a systematic review and meta-analysis in comparison to other injectables.

OBJECTIVE: Intra-articular corticosteroid injections (IACIs) provide temporary symptom relief in osteoarthritis (OA). This meta-analysis investigated the effects of recurrent IACIs at 3 months and beyond. DESIGN: We searched Medline, Embase and Cochrane from inception to January 2021 for randomised controlled trials (RCTs) of patients with OA who received recurrent IACIs compared with other injectables, placebo or no treatment (primary outcomes: pain, function). Mean differences (MDs) with 95% confidence intervals were reported. RESULTS: Ten RCTs were included (eight knee OA (n = 763), two trapeziometacarpal OA (n = 121)). Patients received between 2 and 8 injections, varying by trial. Trials compared recurrent IACIs with hyaluronic acid (HA), platelet-rich plasma (PRP), saline or orgotein (follow-up 3-24 months). Greater improvements in pain, function and QoL at 3-24 months were noted for the comparators than with IACIs, with comparators demonstrating an equal or superior effect, or the intervention effect attenuated during follow-up. Recurrent IACIs demonstrated no benefits in pain or function over placebo at 12-24 months. No serious adverse events were recorded. No studies reported on time-to-future interventions, risk of future prosthetic joint infection or other adverse events associated with subsequent joint replacement. CONCLUSIONS: Recurrent IACIs often provide inferior (or non-superior) symptom relief compared with other injectables (including placebo) at 3 months and beyond. Other injectables (HA, PRP) often yielded greater improvements in pain and function up to 24 months post-injection. Existing RCTs on recurrent IACIs lack sufficient follow-up data to assess disease progression and time-to-future interventions.

Comparative risk of acute myocardial infarction for anti-osteoporosis drugs in primary care: a meta-analysis of propensity-matched cohort findings from the UK Clinical Practice Research Database and the Catalan SIDIAP Database.

The aim of this study was to evaluate the risk of acute myocardial infarction in patients taking osteoporosis medication. Patients were taken from the SIDIAP or CPRD database and were matched using propensity scores. Patients with diabetes and chronic kidney disease taking SERMs were at an increased risk. The results favour the cardiovascular safety of alendronate as a first-line choice for osteoporosis treatment. INTRODUCTION: This study aims to evaluate the comparative safety of anti-osteoporosis drugs based on the observed risk of acute myocardial infarction while on treatment in a primary care setting. METHODS: This is a propensity-matched cohort study and meta-analysis. This study was conducted in two primary care record databases covering UK NHS (CPRD) and Catalan healthcare (SIDIAP) patients during 1995-2014 and 2006-2014, respectively. The outcome was acute myocardial infarction while on treatment. Users of alendronate (reference group) were compared to those of (1) other oral bisphosphonates (OBP), (2) strontium ranelate (SR), and (3) selective oestrogen receptor modulator (SERM), after matching on baseline characteristics (socio-demographics, fracture risk factors, comorbidities, and concomitant drug use) using propensity scores. Multiple imputation was used to handle missing data on confounders and competing risk modelling for the calculation of relative risk (sub-distribution hazard ratios (SHR)) according to therapy. Country-specific data were analysed individually and meta-analysed. RESULTS: A 10% increased risk of acute myocardial infarction was found in users of other bisphosphonates as compared to alendronate users within CPRD. The meta-analysis of CPRD and SIDIAP results showed a 9% increased risk in users of other bisphosphonate as compared to alendronate users. Sensitivity analysis showed SERMS users with diabetes and chronic kidney disease were at an elevated risk. CONCLUSIONS: This study provides additional data on the risk of acute myocardial infarction in patients receiving osteoporosis treatment. The results favour the cardiovascular safety of alendronate as a first-line choice for osteoporosis treatment.

Projections for primary hip and knee replacement surgery up to the year 2060: an analysis based on data from The National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

INTRODUCTION: We estimated the number of primary total hip and knee replacements (THR and TKR) that will need to be performed up to the year 2060. METHODS: We used data from The National Joint Registry for England, Wales, Northern Ireland and the Isle of Man on the volume of primary THRs (n=94,936) and TKRs (n=100,547) performed in 2018. We projected future numbers of THR and TKR using a static estimated rate from 2018 applied to population growth forecast data from the UK Office for National Statistics up to 2060. RESULTS: By 2060, THR and TKR volume would increase from 2018 levels by an estimated 37.7% (n=130,766) and 36.6% (n=137,341), respectively. For both males and females demand for surgery was also higher for patients aged 70 and over, with older patients having the biggest relative increase in volume over time: 70-79 years (44.6% males, 41.2% females); 80-89 years (112.4% males, 85.6% females); 90 years and older (348.0% males, 198.2% females). CONCLUSION: By 2060 demand for hip and knee joint replacement is estimated to increase by almost 40%. Demand will be greatest in older patients (70+ years), which will have significant implications for the health service requiring forward planning given that morbidity and resource use is higher in this population. These issues, coupled with two waves of COVID-19, will impact the ability of health services to deliver timely joint replacement to many patients for a number of years, requiring urgent planning.

Geographical variation in surgical care and mortality following hip fracture in England: a cohort study using the National Hip Fracture Database (NHFD).

We describe variation across geographical regions of England in operations undertaken following presentation of hip fracture and in 30-day mortality. Some significant geographic variation in 30-day mortality was observed particularly for patients with trochanteric hip fractures and warrants further investigation of other aspects of post-hip fracture care INTRODUCTION: Mortality after hip fracture has improved considerably in the UK over recent decades. Our aim here was to describe geographical variation in type of operation performed and 30-day mortality amongst patients in England with hip fracture. METHODS: The National Hip Fracture Database was used to carry out a prospective cohort study of nearly all over-60 year olds with hip fracture in England. These data were linked to Hospital Episode Statistics (HES), allowing us to explore regional variation in the operations performed for three fracture types (intracapsular, trochanteric and subtrochanteric), and use logistic regression models adjusted for demographic and clinical factors to describe associated 30-day mortality. RESULTS: NHFD recorded data for 64,211 patients who underwent surgery in England during 2017. Most had an intracapsular (59%) or trochanteric fracture (35%), and we found significant geographical variation across regions of England in use of total hip replacement (THR) (ranging from 10.1 to 17.4%) for intracapsular fracture and in intermedullary nailing (ranging from 14.9 to 27.0%) of trochanteric fracture. Some geographical variation in mortality amongst intracapsular fracture patients was found, with slightly higher mortality in the East of England (adjusted odds ratio [aOR]: 1.22, 95% CI: 1.02-1.46). Trochanteric fractures showed slightly more variation, with higher 30-day mortality (aOR: 1.40, 95%CI: 1.05-1.88) in the East of England and significantly lower mortality in the North East (aOR: 0.65, 95%CI: 0.46-0.93). CONCLUSIONS: We have identified regional differences in operation type and 30-day mortality amongst hip fracture patients in England. The relationship between surgical approach and mortality has been explored, but the extent to which differential mortality reflects variation in approach to medical assessment, anaesthesia and other aspects of care warrants further investigation.

Determining individual trajectories of joint space loss: improved statistical methods for monitoring knee osteoarthritis disease progression.

OBJECTIVES: Knee osteoarthritis (KOA) progression is frequently monitored by calculating the change in knee joint space width (JSW) measurements. Such differences are small and sensitive to measurement error. We aimed to assess the utility of two alternative statistical modelling methods for monitoring KOA. MATERIAL AND METHODS: We used JSW on radiographs from both the control arm of the Strontium Ranelate Efficacy in Knee Osteoarthritis trial (SEKOIA), a 3-year multicentre, double-blind, placebo-controlled phase three trial, and the Osteoarthritis Initiative (OAI), an open-access longitudinal dataset from the USA comprising participants followed over 8 years. Individual estimates of annualised change obtained from frequentist linear mixed effect (LME) and Bayesian hierarchical modelling, were compared with annualised crude change, and the association of these parameters with change in WOMAC pain was examined. RESULTS: Mean annualised JSW changes were comparable for all estimates, a reduction of around 0.14 mm/y in SEKOIA and 0.08 mm/y in OAI. The standard deviation (SD) of change estimates was lower with LME and Bayesian modelling than crude change (SEKOIA SD = 0.12, 0.12 and 0.21 respectively; OAI SD = 0.08, 0.08 and 0.11 respectively). Estimates from LME and Bayesian modelling were statistically significant predictors of change in pain in SEKOIA (LME P-value = 0.04, Bayes P-value = 0.04), while crude change did not predict change in pain (P-value = 0.10). CONCLUSIONS: Implementation of LME or Bayesian modelling in clinical trials and epidemiological studies, would reduce sample sizes by enabling all study participants to be included in analysis regardless of incomplete follow up, and precision of change estimates would improve. They provide increased power to detect associations with other measures.

Anaesthetic management of an emergency caesarean section in a complex immunologically compromised patient with pre-eclampsia and multifactorial thrombocytopaenia.

A 35-year-old gravida 3, para 0 woman required an emergency caesarean section for pre-eclampsia with severe features including a platelet count of 7 × 109.l-1. The patient's thrombocytopaenia was an acute on chronic presentation. In addition to pre-eclampsia, the patient had a complex background history which included autoimmune lymphoproliferative syndrome, the manifestations of which include autoimmune cytopaenias and recurrent infections. The patient also had common variable immune deficiency and acquired C1-esterase inhibitor deficiency which may cause life-threatening angioedema, including of the airway. In this report, we describe the potential anaesthetic challenges posed by this pre-eclamptic, immunologically compromised patient with severe thrombocytopaenia and the potential for difficult airway, and how these were addressed in a safe and timely manner. Specifically, we highlight the important considerations when performing a general anaesthetic in this unique combination of circumstances. Although the patient's conditions are rare, this case demonstrates that early multidisciplinary team input can help successfully guide the management of medically complex pregnant patients.

Lifetime revision risk for medial unicompartmental knee replacement is lower than expected.

PURPOSE: Unicompartmental knee replacement (UKR) is widely considered to be a pre-total knee replacement (TKR) particularly in the young. The implication of this is that it is sensible to do a UKR, even though it will be revised at some stage, as it will delay the need for a TKR. The chance of a UKR being revised during a patient's life time has not previously been calculated. The aim of this study was to estimate this lifetime revision risks for patients of different ages undergoing UKR. METHODS: Calculations were based on data from a designer series of 1000 medial Oxford UKR with mean 10-year follow up. These UKR were implanted for the recommended indications using the recommended surgical technique. Parametric survival models were developed for patients of different ages based on observed data, and were extrapolated using a Markov model to estimate lifetime revision risk. RESULTS: The estimated lifetime revision risk reduced with increasing age at surgery. Lifetime revision risk at age 55 was 15% (95% CI 12-19), at 65 it was 11% (8-13), at 75 it was 7% (5-9), and at 85 it was 4% (3-5). CONCLUSION: Provided UKR is used appropriately, the lifetime revision risk is markedly lower than expected. UKR should be considered to be a definitive knee replacement rather than a Pre-TKR even in the young. These lifetime estimates, alongside established benefits for UKR in speed of recovery, morbidity, mortality and function, can be discussed with appropriate patients when considering whether to implant a UKR or TKR. LEVEL OF EVIDENCE: III.

The molecular profile of synovial fluid changes upon joint distraction and is associated with clinical response in knee osteoarthritis.

OBJECTIVE: Surgical knee joint distraction (KJD) leads to clinical improvement in knee osteoarthritis (OA) and also apparent cartilage regeneration by magnetic resonance imaging. We investigated if alteration of the joint's mechanical environment during the 6 week period of KJD was associated with a molecular response in synovial fluid, and if any change was associated with clinical response. METHOD: 20 individuals undergoing KJD for symptomatic radiographic knee OA had SF sampled at baseline, midpoint and endpoint of distraction (6 weeks). SF supernatants were measured by immunoassay for 10 predefined mechanosensitive molecules identified in our previous pre-clinical studies. The composite Knee injury and OA Outcome Score-4 (KOOS4) was collected at baseline, 3, 6 and 12 months. RESULTS: 13/20 (65%) were male with mean age 54°±°5yrs. All had Kellgren-Lawrence grade ≥2 knee OA. 6/10 analytes showed statistically significant change in SF over the 6 weeks distraction (activin A; TGFß-1; MCP-1; IL-6; FGF-2; LTBP2), P < 0.05. Of these, all but activin A increased. Those achieving the minimum clinically important difference of 10 points for KOOS4 over 6 months showed greater increases in FGF-2 and TGFß-1 than non-responders. An increase in IL-8 during the 6 weeks of KJD was associated with significantly greater improvement in KOOS4 over 12 months. CONCLUSION: Detectable, significant molecular changes are observed in SF following KJD, that are remarkably consistent between individuals. Preliminary findings appear to suggest that increases in some molecules are associated with clinically meaningful responses. Joint distraction may provide a potential opportunity in the future to define regenerative biomarker(s) and identify pathways that drive intrinsic cartilage repair.

Pay for performance and hip fracture outcomes: an interrupted time series and difference-in-differences analysis in England and Scotland.

AIMS: Hip fractures are associated with high morbidity, mortality, and costs. One strategy for improving outcomes is to incentivize hospitals to provide better quality of care. We aimed to determine whether a pay-for-performance initiative affected hip fracture outcomes in England by using Scotland, which did not participate in the scheme, as a control. MATERIALS AND METHODS: We undertook an interrupted time series study with data from all patients aged more than 60 years with a hip fracture in England (2000 to 2018) using the Hospital Episode Statistics Admitted Patient Care (HES APC) data set linked to national death registrations. Difference-in-differences (DID) analysis incorporating equivalent data from the Scottish Morbidity Record was used to control for secular trends. The outcomes were 30-day and 365-day mortality, 30-day re-admission, time to operation, and acute length of stay. RESULTS: There were 1 037 860 patients with a hip fracture in England and 116 594 in Scotland. Both 30-day (DID -1.7%; 95% confidence interval (CI) -2.0 to -1.2) and 365-day (-1.9%; 95% CI -2.5 to -1.3) mortality fell in England post-intervention when compared with outcomes in Scotland. There were 7600 fewer deaths between 2010 and 2016 that could be attributed to interventions driven by pay-for-performance. A pre-existing annual trend towards increased 30-day re-admissions in England was halted post-intervention. Significant reductions were observed in the time to operation and length of stay. CONCLUSION: This study provides evidence that a pay-for-performance programme improved the outcomes after a hip fracture in England. Cite this article: Bone Joint J 2019;101-B:1015-1023.

Impact of a national enhanced recovery after surgery programme on patient outcomes of primary total knee replacement: an interrupted time series analysis from "The National Joint Registry of England, Wales, Northern Ireland and the Isle of Man".

OBJECTIVE: We aimed to test whether a national Enhanced Recovery After Surgery (ERAS) Programme in total knee replacement (TKR) had an impact on patient outcomes. DESIGN: Natural-experiment (April 2008-December 2016). Interrupted time-series regression assessed impact on trends before-during-after ERAS implementation. SETTING: Primary operations from the UK National Joint Registry (NJR) were linked with Hospital Episode Statistics (HES) data which contains inpatient episodes undertaken in National Health Service (NHS) trusts in England, and Patient Reported Outcome Measures (PROMs). PARTICIPANTS: Patients undergoing primary planned TKR aged ≥18 years. INTERVENTION: ERAS implementation (April 2009-March 2011). OUTCOMES: Regression coefficients of monthly means of Length of stay (LOS), bed day costs, change in Oxford knee scores (OKS) 6-months after surgery, complications (at 6 months), and rates of revision surgeries (at 5 years). RESULTS: 486,579 primary TKRs were identified. Overall LOS and bed-day costs decreased from 5.8 days to 3.7 and from £7607 to £5276, from April 2008 to December 2016. Oxford knee score (OKS) change improved from 15.1 points in April 2008 to 17.1 points in December 2016. Complications decreased from 4.1 % in April 2008 to 1.7 % in March 2016. 5-year revision rates remained stable at 4.8 per 1000 implants years in April 2008 and December 2011. After ERAS, declining trends in LOS and bed costs slowed down; OKS improved, complications remained stable, and revisions slightly increased. CONCLUSIONS: Different secular trends in outcomes for patients having TKR have been observed over the last decade. Although patient outcomes are better than a decade ago ERAS did not improve them at national level.

Rates of knee arthroplasty within one-year of undergoing arthroscopic partial meniscectomy in England: temporal trends, regional and age-group variation in conversion rates.

OBJECTIVE: The aim of this study was to determine the proportion of patients undergoing arthroscopic partial meniscectomy (APM) then subsequently receiving a knee arthroplasty within one or two years, with focus on patients over the age of 60 years and regional variation. METHODS: Patients undergoing APM in England over 20-years (01-April-1997 to 31-March 2017) were identified in the national Hospital Episode Statistics (HES). The proportion of patients undergoing arthroplasty in the same knee within one or two years of APM was determined and trends were analysed over time nationally and by NHS Clinical Commissioning Group (CCG) region. RESULTS: 806,195 APM patients were eligible for analysis with at least one-year of follow up and 746,630 with two-years. The odds of arthroplasty conversion within one year increased over the study period (odds ratio [OR] 3.10 within 1-year in 2014 vs 2000; 95% confidence interval [CI] 2.75-3.50). For patients undergoing APM aged 60 years or older in 2015-16, 9.9% (1689/17,043; 95% CI 9.5-10.4) underwent arthroplasty within 1-year and, in 2014-15, 16.6% (3100/18,734; 95% CI 16.0-17.1) underwent arthroplasty within 2-years. There was greater than 10-fold variation by CCG. CONCLUSIONS: Over the study period, the proportion of patients undergoing arthroplasty within one-year of APM increased. In 2015-16, of patients aged 60 years or older who underwent APM, 10% subsequently underwent knee arthroplasty within one year (17% within two years in 2014-15) and there was a high level of regional variation in this outcome. The development and adoption of national treatment guidance is recommended to improve and standardise treatment selection.

Higher 30-day mortality associated with the use of intramedullary nails compared with sliding hip screws for the treatment of trochanteric hip fractures: a prospective national registry study.

AIMS: The aim of this study was to investigate the association between the type of operation used to treat a trochanteric fracture of the hip and 30-day mortality. PATIENTS AND METHODS: Data on 82 990 patients from the National Hip Fracture Database were analyzed using generalized linear models with incremental case-mix adjustment for patient, non-surgical and surgical characteristics, and socioeconomic factors. RESULTS: The use of short and long intramedullary nails was associated with an increase in 30-day mortality (adjusted odds ratio (OR) 1.125, 95% confidence interval (CI) 1.040 to 1.218; p = 0.004) compared with the use of sliding hip screws (12.5% increase). If this were causative, it would represent 98 excess deaths over the four-year period of the study and one excess death would be caused by treating 112 patients with an intramedullary nail rather than a sliding hip screw. CONCLUSION: There is a 12.5% increase in the risk of 30-day mortality associated with the use of an intramedullary nail compared with a sliding hip screw in the treatment of a trochanteric fractures of the hip.

Association of metabolic syndrome with knee and hand osteoarthritis: A community-based study of women.

OBJECTIVE: It is unclear whether the association between osteoarthritis (OA) and metabolic syndrome (MetS) varies with the site of the affected joint and the presence of pain. Our aim was to describe the association between MetS and radiographic OA (ROA) affecting the knee or the hand in the presence or absence of concurrent joint pain. METHODS: Cross-sectional data of 952 women, aged 45-65years from the Chingford study, a population-based longitudinal cohort of middle-aged women initiated in 1988-1989 in London (UK), was analysed. MetS was defined using the National Cholesterol Education Program Treatment Panel III criteria. Data was collected on components of MetS: waist circumference, triglycerides, high-density lipoprotein (HDL), blood pressure and blood glucose. The outcome was four knee and hand OA groups: painful ROA, ROA only, pain only and neither ROA nor pain (reference category). Multinomial logistic regression models adjusted for age and body mass index (BMI) were used to evaluate the effect of presence of MetS and its individual components on OA subgroups for knee and hand separately. RESULTS: 952 eligible women, aged 45-65years was analysed. A significant association was observed between the presence and the number of MetS with painful knee ROA when adjusted for age; however, this association disappeared when BMI was included in the model. In contrast, the presence and the number of MetS were associated with painful interphalangeal (IPJ) OA after adjusting for both age and BMI. Four out of the five MetS components, including triglycerides, HDL-c, hypertension and glucose, were associated with painful IPJ OA. CONCLUSIONS: MetS is associated with painful IPJ OA but not with knee OA once BMI is taking into consideration. Further attention to MetS and OA at different sites is needed to understand the metabolic phenotype in OA.

Do portable nursing stations within bays of hospital wards reduce the rate of inpatient falls? An interrupted time-series analysis.

Background: falls can negatively affect patients, resulting in loss of independence and functional decline and have substantial healthcare costs. Hospitals are a high-risk falls environment and regularly introduce, but seldom evaluate, policies to reduce inpatient falls. This study evaluated whether introducing portable nursing stations in ward bays to maximise nurse-patient contact time reduced inpatient falls. Methods: inpatient falls data from local hospital incident reporting software (Datix) were collected monthly (April 2014-December 2017) from 17 wards in Stoke Mandeville and Wycombe General Hospitals, the UK. Portable nursing stations were introduced in bays on these wards from April 2016. We used a natural experimental study design and interrupted time series analysis to evaluate changes in fall rates, measured by the monthly rate of falls per 1000 occupied bed days (OBDs). Results: the wards reported 2875 falls (April 2014-December 2017). The fallers' mean age was 78 (SD = 13) and 58% (1624/2817) were men. Most falls, 99.41% (2858/2875), resulted in none, low or moderate harm, 0.45% (13/2875) in severe harm and 0.14% (4/2875) in death. The monthly falls rate increased by 0.119 per 1000 OBDs (95% CI: 0.045, 0.194; P = 0.002) before April 2016, then decreased by 0.222 per 1000 OBDs (95% CI: -0.350, -0.093; P = 0.001) until December 2017. At 12 months post-intervention, the absolute difference between the estimated post-intervention trend and pre-intervention projected estimate was 2.84 falls per 1000 OBDs, a relative reduction of 26.71%. Conclusion: portable nursing stations were associated with lower monthly falls rates and could reduce inpatient falls across the NHS.

Social inequality and fractures-secular trends in the Danish population: a case-control study.

We examined links between markers of social inequality and fracture risk in the Danish population, demonstrating that high income and being married are associated with a significantly lower risk. INTRODUCTION: We explored whether the risk of hip, humerus, and wrist fracture was associated with markers of inequality using data from Danish health registries. METHODS: All patients 50 years or older with a primary hip (ICD10 S720, S721, S722, and S729) humerus (ICD10 S422, S423, S424, S425, S426, and S427), or wrist (ICD10: S52) fracture were identified from 1/1/1995 to 31/12/2011. Fracture patients were matched 1:1 by age, sex, and year of fracture, to a non-fracture control. Markers of inequality were as follows: income (fifths); marital status (married, divorced, widowed, or unmarried); area of residence (remote, rural, intermediate, or urban). Conditional logistic regression was used to investigate associations between these exposures, and risk of fracture, adjusting for covariates (smoking, alcohol, and Charlson co-morbidity). Interactions were fitted between exposure and covariates where appropriate. RESULTS: A total of 189,838 fracture patients (37,500 hip, 45,602 humerus, and 106,736 wrist) and 189,838 controls were included. Mean age was 73.9 years (hip), 67.5 years (humerus), and 65.3 years (wrist). High income (5th quintile) was significantly associated with a lower odds ratio of all three fractures, compared to average income (3rd quintile). Married subjects had a significantly decreased odds ratio across all three fractures. However, no overall secular difference was observed regarding the influence of the markers of inequality. CONCLUSION: In conclusion, we have demonstrated important, stable associations between social inequality, assessed using income, marital status, and area of residence, and fracture at the population level. These findings can inform approaches to healthcare, and suggest that much thought should be given to novel interventions aimed especially at those living alone, and ideally societal measures to reduce social inequality.

Development and validation of a clinical prediction model for patient-reported pain and function after primary total knee replacement surgery.

To develop and validate a clinical prediction model of patient-reported pain and function after undergoing total knee replacement (TKR). We used data of 1,649 patients from the Knee Arthroplasty Trial who received primary TKR across 34 centres in the UK. The external validation included 595 patients from Southampton University Hospital, and Nuffield Orthopaedic Centre (Oxford). The outcome was the Oxford Knee Score (OKS) 12-month after TKR. Pre-operative predictors including patient characteristics and clinical factors were considered. Bootstrap backward linear regression analysis was used. Low pre-operative OKS, living in poor areas, high body mass index, and patient-reported anxiety or depression were associated with worse outcome. The clinical factors associated with worse outcome were worse pre-operative physical status, presence of other conditions affecting mobility and previous knee arthroscopy. Presence of fixed flexion deformity and an absent or damaged pre-operative anterior cruciate ligament (compared with intact) were associated with better outcome. Discrimination and calibration statistics were satisfactory. External validation predicted 21.1% of the variance of outcome. This is the first clinical prediction model for predicting self-reported pain and function 12 months after TKR to be externally validated. It will help to inform to patients regarding expectations of the outcome after knee replacement surgery.

Harmonising measures of knee and hip osteoarthritis in population-based cohort studies: an international study.

OBJECTIVE: Population-based osteoarthritis (OA) cohorts provide vital data on risk factors and outcomes of OA, however the methods to define OA vary between cohorts. We aimed to provide recommendations for combining knee and hip OA data in extant and future population cohort studies, in order to facilitate informative individual participant level analyses. METHOD: International OA experts met to make recommendations on: 1) defining OA by X-ray and/or pain; 2) compare The National Health and Nutrition Examination Survey (NHANES)-type OA pain questions; 3) the comparability of the Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) scale to NHANES-type OA pain questions; 4) the best radiographic scoring method; 5) the usefulness of other OA outcome measures. Key issues were explored using new analyses in two population-based OA cohorts (Multicenter Osteoarthritis Study; MOST and Osteoarthritis Initiative OAI). RESULTS: OA should be defined by both symptoms and radiographs, with symptoms alone as a secondary definition. Kellgren and Lawrence (K/L) grade ≥2 should be used to define radiographic OA (ROA). The variable wording of pain questions can result in varying prevalence between 41.0% and 75.4%, however questions where the time anchor is similar have high sensitivity and specificity (91.2% and 89.9% respectively). A threshold of 3 on a 0-20 scale (95% CI 2.1, 3.9) in the WOMAC pain subscale demonstrated equivalence with the preferred NHANES-type question. CONCLUSION: This research provides recommendations, based on expert agreement, for harmonising and combining OA data in existing and future population-based cohorts.

Is the rate of revision of 36 mm metal-on-metal total hip arthroplasties with Pinnacle acetabular components related to the year of the initial operation? an interrupted time-series analysis using data from the National Joint Registry for England and Wales.

AIMS: The aim of this study was to determine whether the rates of revision for metal-on-metal (MoM) total hip arthroplasties (THAs) with Pinnacle components varied according to the year of the initial operation, and compare these with the rates of revision for other designs of MoM THA. PATIENTS AND METHODS: Data from the National Joint Registry for England and Wales included 36 mm MoM THAs with Pinnacle acetabular components which were undertaken between 2003 and 2012 with follow-up for at least five years (n = 10 776) and a control group of other MoM THAs (n = 13 817). The effect of the year of the primary operation on all-cause rates of revision was assessed using Cox regression and interrupted time-series analysis. RESULTS: For MoM THAs involving Pinnacle components, those undertaken between 2007 and 2012 had higher rates of revision compared with those undertaken between 2004 and 2006 (hazard ratio (HR) 2.01; 95% confidence interval (CI) 1.57 to 2.57; p < 0.001). For THAs undertaken during and after 2007, the number of revisions per 1000 implant-years at risk significantly increased by 5.20 (95% CI 0.52 to 9.89; p = 0.033) compared with those undertaken before this time. In the control group, THAs undertaken between 2007 and 2012 also had higher rates of revision (HR 1.77; 95% CI 1.49 to 2.10; p < 0.001), with revisions per 1000 implant-years for those undertaken during and after 2007 significantly increasing by 6.13 (95% CI 1.42 to 10.83; p = 0.016). CONCLUSION: The five-year revision rates were significantly increased for all primary MoM THAs undertaken from 2007 onwards. Contrary to recent reports, this finding was not specific to those involving Pinnacle acetabular components and may be explained by increased surveillance and recent lowering of the threshold for revision. Cite this article: Bone Joint J 2018;100-B:33-41.

Using alternative forage species to reduce emissions of the greenhouse gas nitrous oxide from cattle urine deposited onto soil.

Grazed pastures are a major contributor to emissions of the greenhouse gas nitrous oxide (N2O), and urine deposition from grazing animals is the main source of the emissions. Incorporating alternative forages into grazing systems could be an approach for reducing N2O emissions through mechanisms such as release of biological nitrification inhibitors from roots and increased root depth. Field plot and lysimeter (intact soil column) trials were conducted in a free draining Horotiu silt loam soil to test whether two alternative forage species, plantain (Plantago lanceolate L.) and lucerne (Medicago sativa L.), could reduce N2O emissions relative to traditional pasture species, white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.). The amounts of N2O emitted from the soil below each forage species, which all received the same cow urine at the same rates, was measured using an established static chamber method. Total N2O emissions from the plantain, lucerne and perennial ryegrass controls (without urine application) were generally very low, but emissions from the white clover control were significantly higher. When urine was applied in autumn or winter N2O emissions from plantain were lower compared with those from perennial ryegrass or white clover, but this difference was not found when urine was applied in summer. Lucerne had lower emissions in winter but not in other seasons. Incorporation of plantain into grazed pasture could be an approach to reduce N2O emissions. However, further work is required to understand the mechanisms for the reduced emissions and the effects of environmental conditions in different seasons.

Risk of venous thromboembolism among users of different anti-osteoporosis drugs: a population-based cohort analysis including over 200,000 participants from Spain and the UK.

The venous thromboembolism risk among anti-osteoporotics is unknown. In this primary care study, the risk with other bisphosphonates [1.05 (0.94-1.18) and 0.96 (0.78-1.18)], strontium [0.90 (0.61-1.34) and 1.19 (0.82-1.74)], in the UK and Spain respectively, and denosumab [1.77 (0.25-12.66)] and teriparatide [1.27 (0.59-2.71)] in Spain, did not differ versus alendronate. INTRODUCTION: Most of the known adverse drug reactions described for anti-osteoporosis medication (AOM) have been described in studies comparing AOM users to non-users. We aimed to compare the risk of venous thromboembolism (VTE) among incident users of different AOM compared to alendronate (first line therapy). METHODS: Two cohort studies were performed using data from the UK (CPRD) and Spain (BIFAP) primary care records separately. All patients aged ≥ 50 years with at least 1 year of data available and a new prescription or dispensation of AOM (date for therapy initiation) during 2000-2014 (CPRD) or 2001-2013 (BIFAP) were included. Users of raloxifene/bazedoxifene were excluded from both databases. Five exposure cohorts were identified according to first treatment: (1) alendronate, (2) other bisphosphonates, (3) strontium ranelate, (4) denosumab, and (5) teriparatide. Participants were followed from the day after therapy initiation to the earliest of a treated VTE (cases), end of AOM treatment (defined by a refill gap of 180 days), switching to an alternative AOM, drop-out, death, or end of study period. Incidence rates of VTE were estimated by cohort. Adjusted hazard ratios (HR 95%CI) were estimated according to drug used. RESULTS: Overall, 2035/159,209 (1.28%) in CPRD and 401/83,334 (0.48%) in BIFAP had VTE. Compared to alendronate, adjusted HR of VTE were 1.05 (0.94-1.18) and 0.96 (0.78-1.18) for other bisphosphonates, and 0.90 (0.61-1.34) and 1.19 (0.82-1.74) for strontium in CPRD and BIFAP, respectively; 1.77 (0.25-12.66) for denosumab and 1.27 (0.59-2.71) for teriparatide in BIFAP. CONCLUSIONS: VTE risk during AO therapy did not differ by AOM drug use. Our data does not support an increased risk of VTE associated with strontium ranelate use in the community.