The clinical and cost-effectiveness of elective primary total knee replacement with PAtellar Resurfacing compared to selective patellar resurfacing: a pragmatic multicentre randomized controlled Trial (PART).

Aims: During total knee replacement (TKR), surgeons can choose whether or not to resurface the patella, with advantages and disadvantages of each approach. Recently, the National Institute for Health and Care Excellence (NICE) recommended always resurfacing the patella, rather than never doing so. NICE found insufficient evidence on selective resurfacing (surgeon's decision based on intraoperative findings and symptoms) to make recommendations. If effective, selective resurfacing could result in optimal individualized patient care. This protocol describes a randomized controlled trial to evaluate the clinical and cost-effectiveness of primary TKR with always patellar resurfacing compared to selective patellar resurfacing. Methods: The PAtellar Resurfacing Trial (PART) is a patient- and assessor-blinded multicentre, pragmatic parallel two-arm randomized superiority trial of adults undergoing elective primary TKR for primary osteoarthritis at NHS hospitals in England, with an embedded internal pilot phase (ISRCTN 33276681). Participants will be randomly allocated intraoperatively on a 1:1 basis (stratified by centre and implant type (cruciate-retaining vs cruciate-sacrificing)) to always resurface or selectively resurface the patella, once the surgeon has confirmed sufficient patellar thickness for resurfacing and that constrained implants are not required. The primary analysis will compare the Oxford Knee Score (OKS) one year after surgery. Secondary outcomes include patient-reported outcome measures at three months, six months, and one year (Knee injury and Osteoarthritis Outcome Score, OKS, EuroQol five-dimension five-level questionnaire, patient satisfaction, postoperative complications, need for further surgery, resource use, and costs). Cost-effectiveness will be measured for the lifetime of the patient. Overall, 530 patients will be recruited to obtain 90% power to detect a four-point difference in OKS between the groups one year after surgery, assuming up to 40% resurfacing in the selective group. Conclusion: The trial findings will provide evidence about the clinical and cost-effectiveness of always patellar resurfacing compared to selective patellar resurfacing. This will inform future NICE guidelines on primary TKR and the role of selective patellar resurfacing.

Long-term changes in blood metal ion levels in patients with hip resurfacing implants: implications for patient surveillance after 10 years follow-up.

BACKGROUND: Studies investigating changes in blood metal ion levels during the second decade of the implant lifetime in MoM hip resurfacing patients are scarce. METHODS: Patients implanted with either Birmingham Hip Resurfacing (BHR) or Articular Surface Replacement (ASR) hip resurfacings with >10 years follow-up and repeated blood metal ion measurements were identified at 2 large specialist European arthroplasty centres. After excluding patients with initial metal ion levels >7 ppb, the proportion of patients with an increase in blood metal ion levels above previously validated implant-specific thresholds (cobalt 2.15 ppb for unilateral implants, cobalt or chromium 5.5 ppb for bilateral) was assessed. RESULTS: We included 2743 blood metal ion measurements from 457 BHR patients (555 hips) and 216 ASR patients (263 hips). Of patients with initial metal ion levels below implant specific thresholds, increases in cobalt or chromium level, respectively, to above these thresholds during the second decade were seen as follows: unilateral BHR (cobalt = 15.6%), unilateral ASR (cobalt = 13.8%), bilateral BHR (cobalt = 8.2%, chromium = 11.8%), bilateral ASR (cobalt = 8.5%, chromium = 4.3%). Measurement-to-measurement changes exceeding +2.15 ppb or +5.5 ppb were, however, uncommon during the second decade. Subgroup results with small diameter (<50 mm) implants were similar. CONCLUSIONS: We recommend less frequent blood metal ion measurements are needed (every 3 to 5 years) for hip resurfacing patients if initial values were below 7ppb.

Clinical effectiveness of patellar resurfacing, no resurfacing and selective resurfacing in primary total knee replacement: systematic review and meta-analysis of interventional and observational evidence.

BACKGROUND: Patellar resurfacing is optional during total knee replacement (TKR). Some surgeons always resurface the patella, some never resurface, and others selectively resurface. Which resurfacing strategy provides optimal outcomes is unclear. We assessed the effectiveness of patellar resurfacing, no resurfacing, and selective resurfacing in primary TKR. METHODS: A systematic review and meta-analysis was performed. MEDLINE, Embase, Web of Science, The Cochrane Library, and bibliographies were searched to November 2021 for randomised-control trials (RCTs) comparing outcomes for two or more resurfacing strategies (resurfacing, no resurfacing, or selective resurfacing) in primary TKR. Observational studies were included if limited or no RCTs existed for resurfacing comparisons. Outcomes assessed were patient reported outcome measures (PROMs), complications, and further surgery. Study-specific relative risks [RR] were aggregated using random-effects models. Quality of the evidence was assessed using GRADE. RESULTS: We identified 33 RCTs involving 5,540 TKRs (2,727 = resurfacing, 2,772 = no resurfacing, 41 = selective resurfacing). One trial reported on selective resurfacing. Patellar resurfacing reduced anterior knee pain compared with no resurfacing (RR = 0.65 (95% CI = 0.44-0.96)); there were no significant differences in PROMs. Resurfacing reduced the risk of revision surgery (RR = 0.63, CI = 0.42-0.94) and other complications (RR = 0.54, CI = 0.39-0.74) compared with no resurfacing. Quality of evidence ranged from high to very low. Limited observational evidence (5 studies, TKRs = 215,419) suggested selective resurfacing increased the revision risk (RR = 1.14, CI = 1.05-1.22) compared with resurfacing. Compared with no resurfacing, selective resurfacing had a higher risk of pain (RR = 1.25, CI = 1.04-1.50) and lower risk of revision (RR = 0.92, CI = 0.85-0.99). CONCLUSIONS: Level 1 evidence supports TKR with patellar resurfacing over no resurfacing. Resurfacing has a reduced risk of anterior knee pain, revision surgery, and complications, despite PROMs being comparable. High-quality RCTs involving selective resurfacing, the most common strategy in the UK and other countries, are needed given the limited observational data suggests selective resurfacing may not be effective over other strategies.

Clinical effectiveness and safety of spinal anaesthesia compared with general anaesthesia in patients undergoing hip fracture surgery using a consensus-based core outcome set and patient-and public-informed outcomes: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: We conducted a systematic review and meta-analysis of contemporary RCTs to determine the clinical effectiveness of spinal vs general anaesthesia (SA vs GA) in patients undergoing hip fracture surgery using a consensus-based core outcome set, and outcomes defined as important by patient and public involvement (PPI) initiatives. METHODS: RCTs comparing any of the core outcomes (mortality, time from injury to surgery, acute coronary syndrome, hypotension, acute kidney injury, delirium, pneumonia, orthogeriatric input, being out of bed at day 1 postoperatively, and pain) or PPI-defined outcomes (return to preoperative residence, quality of life, and mobility status) between SA and GA were identified from MEDLINE, Embase, Cochrane Library, and Web of Science (2000 to February 2022). Pooled relative risks (RRs) and mean differences (95% confidence intervals [CIs]) were estimated. RESULTS: There was no significant difference in the risk of delirium comparing SA vs GA (RR=1.07; 95% CI, 0.90-1.29). Comparing SA vs GA, the RR for mortality was 0.56 (95% CI, 0.22-1.44) in-hospital, 1.07 (95% CI, 0.52-2.23) at 30 days, and 1.08 (95% CI, 0.55-2.12) at 90 days. Spinal anaesthesia reduced the risk of acute kidney injury compared with GA: RR=0.59 (95% CI, 0.39-0.89). There were no significant differences in the risk of other outcomes. Few studies reported PPI-defined outcomes, with most studies reporting on one to three core outcomes. CONCLUSIONS: Except for acute kidney injury, there were no differences between SA and GA in hip fracture surgery when using a consensus-based core outcome set and patient and public involvement-defined outcomes. Most studies reported limited outcomes from the core outcome set, and few reported outcomes important to patients, which should be considered when designing future RCTs. PROSPERO REGISTRATION: CRD42021275206.

Hand Carpometacarpal Joint Instability in Elite Boxers: Injury Characteristics, Surgical Technique, and Outcomes.

PURPOSE: We describe a single-surgeon's experience of managing hand carpometacarpal joint (CMCJ) instability in elite boxers, focusing on injury characteristics, surgical technique, and outcomes. METHODS: This retrospective cohort included consecutive elite boxers undergoing surgery for hand CMCJ instability from 2009 to 2021. CMC joint instability is usually clear on clinical examination using a 'seesaw' test. All cases had a plain radiograph and in equivocal cases for instability advanced imaging such as MRI or ultrasound scan. CMCJs were accessed via longitudinal incisions between index/middle rays, and additionally ring/little. Often marked deficiency in the CMCJ ligamentous capsule was seen. The articular surfaces were decorticated to cancellous bone and autogenous bone graft impacted. The CMCJs were fixed in extension using various methods, latterly memory staples. Outcomes included radiographic fusion, return to boxing, and complications. RESULTS: Forty hands had surgery in 38 boxers. In total, 101 CMCJs were fused, with an average of 2.5 joints per patient. Patients were mainly young (mean age 24.1 years), male (37/38) with the trailing hand more commonly affected (trailing hand 87.5%, leading hand 12.5%). The most frequently fused CMCJ was the index (97.5%, n = 39), then middle (95%, n = 38), ring (45%, n = 18), and little (15%, n = 6). There were 82% (31/38) of patients who returned to the same level of boxing at a median of 8 months from surgery (range 3-27 months). Three patients had revision surgery for non-union, a median of 10.3 months after initial surgery (range 9.4-133.1 months): 2 for index/middle and one for the little CMCJ. All 3 revisions fused and the patients returned to boxing at the same level, although the little CMCJ required a second bone graft and fixation. CONCLUSIONS: Patients can achieve full recovery after treatment of CMCJ instability, and most can return to boxing at the same level with little risk of complications. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Extensor hood injuries in elite boxers: injury characteristics, surgical technique and outcomes.

We describe our experience of managing extensor hood injuries in boxers (57 fingers). The diagnosis was mostly clinical, with imaging only if the diagnosis was equivocal. The middle (61%) and index (26%) digits were most frequently injured. On exploration, 26% had no hood tear, however all required tenolysis from the adherent capsule. Of 42 hood tears, 15 were central splits between adjacent extensor tendons in the index or little fingers,15 tears were on the ulna side of the extensor tendon and 12 tears were on the radial side. A pseudobursa was encountered in 35%, capsular tears in 28% and chondral injury in one patient. Longitudinal curved metacarpophalangeal joint incisions were used, with hood repair performed in flexion using a locked running suture. Mean postoperative metacarpophalangeal joint flexion was 90°. Ninety-eight per cent returned to the same level of boxing at a mean of 8 months (range 1-24) from surgery. One finger was revised for re-rupture 6 months later. A reproducible technique for treating these injuries is described, with patients able to return to boxing with little risk of complications.Level of evidence: IV.

The influence of mode of anaesthesia on perioperative outcomes in people with hip fracture: a prospective cohort study from the National Hip Fracture Database for England, Wales and Northern Ireland.

BACKGROUND: Delirium is common after hip fracture surgery, affecting up to 50% of patients. The incidence of delirium may be influenced by mode and conduct of anaesthesia. We examined the effect of spinal anaesthesia (with and without sedation) compared with general anaesthesia on early outcomes following hip fracture surgery, including delirium. METHODS: We used prospective data on 107,028 patients (2018 to 2019) from the National Hip Fracture Database, which records all hip fractures in patients aged 60 years and over in England, Wales and Northern Ireland. Patients were grouped by anaesthesia: general (58,727; 55%), spinal without sedation (31,484; 29%), and spinal with sedation (16,817; 16%). Outcomes (4AT score on post-operative delirium screening; mobilisation day one post-operatively; length of hospital stay; discharge destination; 30-day mortality) were compared between anaesthetic groups using multivariable logistic and linear regression models. RESULTS: Compared with general anaesthesia, spinal anaesthesia without sedation (but not spinal with sedation) was associated with a significantly reduced risk of delirium (odds ratio (OR)=0.95, 95% confidence interval (CI)=0.92-0.98), increased likelihood of day one mobilisation (OR=1.06, CI=1.02-1.10) and return to original residence (OR=1.04, CI=1.00-1.07). Spinal without sedation (p<0.001) and spinal with sedation (p=0.001) were both associated with shorter hospital stays compared with general anaesthesia. No differences in mortality were observed between anaesthetic groups. CONCLUSIONS: Spinal and general anaesthesia achieve similar outcomes for patients with hip fracture. However, this equivalence appears to reflect improved perioperative outcomes (including a reduced risk of delirium, increased likelihood of mobilisation day one post-operatively, shorter length of hospital stay and improved likelihood of returning to previous residence on discharge) among the sub-set of patients who received spinal anaesthesia without sedation. The role and effect of sedation should be studied in future trials of hip fracture patients undergoing spinal anaesthesia.

Trauma care in older people: charting a path from outlier to excellence.

Trauma in older people leads to substantial morbidity and mortality. The National Hip Fracture Database (NHFD) has driven improved practice with units compared to identify outliers. In 2013, our unit was an outlier for mortality post hip fracture (30-day mortality 12.2% vs. 8.3% nationally). This triggered external review. In 2019 the unit was highlighted as an exemplar in the UK. We describe the process that moved us from outlier to outstanding. After the initial review process, we made changes to our healthcare system, with regular reassessment of progress and care quality. Examples include a dedicated hip fracture unit, strong leadership (Nursing, Orthopaedic, Geriatrician, Anaesthetic), consultant-led in-depth monthly mortality reviews, changes to admission pathways and delirium prevention. Improvements were seen in all aspects of hip fracture care in 2019 compared with 2012. Thirty-day case-mixed adjusted mortality halved (12.2-6.1%), with substantial reductions in reoperations and pressure sores. Length of stay reduced by 5.9 days. In 2019 our unit's performance was significantly above the national average for all six indicators assessed by NHFD: prompt orthogeriatric review (97% vs. 91% national average), prompt surgery (85% vs. 68%); NICE compliant surgery (85% vs. 74%); prompt mobilisation (93% vs. 81%); not delirious postoperatively (77% vs. 69%); return to original residence (78% vs. 71%). The NHFD highlighted our Unit as one of nine (from 175 total) highly performing UK trusts. We summarise our service development and improvement work undertaken to achieve 'outstanding' status, which provides a valuable template to units managing trauma in older people.

The risk of all-cause mortality, heart outcomes, cancer, and neurodegenerative disorders with cobalt-chrome-containing total hip arthroplasty implants : an analysis of the National Joint Registry.

AIMS: A recent report from France suggested an association between the use of cobalt-chrome (CoCr) femoral heads in total hip arthroplasties (THAs) and an increased risk of dilated cardiomyopathy and heart failure. CoCr is a commonly used material in orthopaedic implants. If the reported association is causal, the consequences would be significant given the millions of joint arthroplasties and other orthopaedic procedures in which CoCr is used annually. We examined whether CoCr-containing THAs were associated with an increased risk of all-cause mortality, heart outcomes, cancer, and neurodegenerative disorders in a large national database. METHODS: Data from the National Joint Registry was linked to NHS English hospital inpatient episodes for 374,359 primary THAs with up to 14.5 years' follow-up. We excluded any patients with bilateral THAs, knee arthroplasties, indications other than osteoarthritis, aged under 55 years, and diagnosis of one or more outcome of interest before THA. Implants were grouped as either containing CoCr or not containing CoCr. The association between implant construct and the risk of all-cause mortality and incident heart failure, cancer, and neurodegenerative disorders was examined. RESULTS: There were 158,677 individuals (42.4%) with an implant containing CoCr. There were 47,963 deaths, 27,332 heart outcomes, 35,720 cancers, and 22,025 neurodegenerative disorders. There was no evidence of an association between patients with CoCr implants and higher rates of any of the outcomes. CONCLUSION: CoCr-containing THAs did not have an increased risk of all-cause mortality, or clinically meaningful heart outcomes, cancer, or neurodegenerative disorders into the second decade post-implantation. Our findings will help reassure clinicians and the increasing number of patients receiving primary THA worldwide that the use of CoCr-containing implants is not associated with significant adverse systemic effects. Cite this article: Bone Joint J 2022;104-B(3):359-367.

The risk of all-cause mortality, heart outcomes, cancer, and neurodegenerative disorders with cobalt-chrome-containing total hip arthroplasty implants : an analysis of the National Joint Registry.

AIMS: A recent report from France suggested an association between the use of cobalt-chrome femoral heads in total hip arthroplasties (THAs) and an increased risk of dilated cardiomyopathy and heart failure. Cobalt-chrome is a commonly used material in orthopaedic implants. If the reported association is causal, the consequences would be significant given the millions of joint replacements and other orthopaedic procedures in which cobalt-chrome is used annually. We examined whether cobalt-chrome-containing THAs were associated with an increased risk of all-cause mortality, heart outcomes, cancer, and neurodegenerative disorders in a large national database. METHODS: Data from the National Joint Registry was linked to NHS English hospital inpatient episodes for 374,359 primary THAs with up to 14.5 years follow-up. We excluded any patients with bilateral THAs, knee replacements, indications other than osteoarthritis, aged under 55 years, and diagnosis of one or more outcome of interest before THA. Implants were grouped as either containing cobalt-chrome or not containing cobalt-chrome. The association between implant construct and the risk of all-cause mortality and incident heart failure, cancer, and neurodegenerative disorders was examined. RESULTS: There were 158,677 individuals (42.4%) with an implant containing cobalt-chrome. There were 47,963 deaths, 27,332 heart outcomes, 35,720 cancers, and 22,025 neurodegenerative disorders. There was no evidence of an association that patients with cobalt-chrome implants had higher rates of any of the outcomes. CONCLUSION: Cobalt-chrome-containing THAs did not have an increased risk of all-cause mortality, or clinically meaningful heart outcomes, cancer or neurodegenerative disorders into the second decade post-implantation. Our findings will help reassure clinicians and the increasing number of patients receiving primary THA worldwide that the use of cobalt-chrome containing implants is not associated with significant adverse systemic effects.

How much does a Medical and Healthcare Products Regulatory Agency medical device alert for metal-on-metal hip arthroplasty patients really cost?

BACKGROUND: Many worldwide regulatory authorities recommend regular surveillance of metal-on-metal hip arthroplasty patients given high failure rates. However, concerns have been raised about whether such regular surveillance, which includes asymptomatic patients, is evidence-based and cost-effective. We determined: (1) the cost of implementing the 2015 MHRA surveillance in "at-risk" Birmingham Hip Resurfacing (BHR) patients; and (2) how many asymptomatic hips with adverse reactions to metal debris (ARMD) would have been missed without patient recall. METHODS: All BHR patients eligible for the 2015 MHRA recall (all females, and males with head sizes ⩽46 mm, regardless of symptoms) at one centre were invited for review (hips = 707; patients = 593). All patients were investigated (Oxford Hip Score, radiographs, blood metal ions, and targeted cross-sectional imaging) and managed accordingly. Surveillance costs were calculated using finance department data. RESULTS: The surveillance cost £105,921.79 (range £147.76-£257.50/patient). Radiographs (£39,598) and nurse practitioner time/assistance (£23,618) accounted for 60% of overall costs. 31 hips had ARMD on imaging (12 revised; 19 under surveillance). All revisions were symptomatic. 7 hips with ARMD under surveillance were asymptomatic and remain under regular review. The number needed to treat to avoid missing one asymptomatic ARMD case was 101 patients, representing a cost of £18,041 to avoid one asymptomatic case. CONCLUSIONS: Implementing MHRA surveillance for "at-risk" BHR patients was extremely costly. The risk of asymptomatic ARMD was low with the BHR (1%), suggesting recommended follow-up in asymptomatic patients is not cost efficient. This raises concerns about the increasingly intensive surveillance recommended in the 2017 MHRA guidance for metal-on-metal hip patients.

The effect of surgical approach in total knee replacement on outcomes. An analysis of 875,166 elective operations from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

BACKGROUND: Total knee replacement (TKR) is clinically and cost-effective. The surgical approach employed influences the outcome, however there is little generalisable and robust evidence to guide practice. We compared outcomes between the common primary TKR surgical approaches. METHODS: 875,166 primary TKRs captured in the National Joint Registry, linked to hospital inpatient, mortality and patient reported outcome measures (PROMs) data, with up to 15.75 years follow-up were analysed. There were 10 surgical approach groups: medial parapatellar, midvastus, subvastus, lateral parapatellar, 'other' and their minimally invasive versions. Survival methods were used to compare revision rates and 45-day mortality. Groups were compared using Cox proportional hazards regression and Flexible Parametric Survival Modelling (FPM). Confounders included age at surgery, sex, risk group (indications additional to osteoarthritis), American Society of Anesthesiologists grade, TKR fixation, year of primary, body mass index, and for mortality, deprivation and Charlson comorbidity subgroups. PROMs were analysed with regression modelling or non-parametric methods. RESULTS: The conventional midvastus approach was associated with lower revision rates (Hazard Rate Ratio (HRR) 0.80 (95% CI 0.71-0.91) P = 0.001) and the lateral parapatellar with higher revision rates (HRR 1.35 (95% CI 1.12-1.63) P = 0.002) compared to the conventional medial parapatellar approach. Mortality rates were similar between approaches. PROMs showed statistically significant, but not clinically important, differences. CONCLUSIONS: There is little difference in PROMs between the various surgical approaches in TKR with all resulting in good outcomes. However, the conventional midvastus approach (used in 3% of cases) was associated with a 20% reduced risk of revision surgery compared to the most commonly used knee approach (the conventional medial parapatellar: used in 91.9% of cases). This data supports the use of the midvastus approach and thus surgeons should consider utilising this approach more frequently. Minimally invasive approaches did not appear to convey any clinical advantage in this study over conventional approaches for primary TKR.

Patellar resurfacing during primary total knee replacement is associated with a lower risk of revision surgery.

AIMS: Debate remains whether the patella should be resurfaced during total knee replacement (TKR). For non-resurfaced TKRs, we estimated what the revision rate would have been if the patella had been resurfaced, and examined the risk of re-revision following secondary patellar resurfacing. METHODS: A retrospective observational study of the National Joint Registry (NJR) was performed. All primary TKRs for osteoarthritis alone performed between 1 April 2003 and 31 December 2016 were eligible (n = 842,072). Patellar resurfacing during TKR was performed in 36% (n = 305,844). The primary outcome was all-cause revision surgery. Secondary outcomes were the number of excess all-cause revisions associated with using TKRs without (versus with) patellar resurfacing, and the risk of re-revision after secondary patellar resurfacing. RESULTS: The cumulative risk of all-cause revision at ten years was higher (p < 0.001) in primary TKRs without patellar resurfacing (3.54% (95% confidence interval (CI) 3.47 to 3.62)) compared to those with resurfacing (3.00% (95% CI 2.91 to 3.11)). Using flexible parametric survival modelling, we estimated one 'excess' revision per 189 cases performed where the patella was not resurfaced by ten years (equivalent to 2,842 excess revisions in our cohort). The risk of all-cause re-revision following secondary patellar resurfacing was 4.6 times higher than the risk of revision after primary TKR with patellar resurfacing (at five years from secondary patellar resurfacing, 8.8% vs 1.9%). CONCLUSION: Performing TKR without patellar resurfacing was associated with an increased risk of revision. Secondary patellar resurfacing led to a high risk of re-revision. This represents a potential substantial healthcare burden that should be considered when forming treatment guidelines and commissioning services. Cite this article: Bone Joint J 2021;103-B(5):864-871.

Patients Receiving a Primary Unicompartmental Knee Replacement Have a Higher Risk of Revision but a Lower Risk of Mortality Than Predicted Had They Received a Total Knee Replacement: Data From the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man.

BACKGROUND: To determine unicompartmental (UKR) and total knee replacement (TKR) revision rates, compare UKR revision rates with what they would have been had they received TKR instead, and assess subsequent re-revision and 90-day mortality rates. METHODS: Using National Joint Registry data, we estimated UKR and TKR revision and mortality rates. Flexible parametric survival modeling (FPM) was used to model failure in TKR and make estimates for UKR. Kaplan-Meier estimates were used to compare cumulative re-revision for revised UKRs and TKRs. RESULTS: Ten-year UKR revision rates were 2.5 times higher than expected from TKR, equivalent to 70 excess revisions/1000 cases within 10 years (5861 excess revisions in this cohort). Revision rates were 2.5 times higher for the highest quartile volume UKR surgeons compared to the same quartile for TKR and 3.9 times higher for the lowest quartiles respectively. Re-revision rates of revised TKRs (10 years = 17.5%, 95% confidence interval [CI] 16.4-18.7) were similar to revised UKRs (15.2%, 95% CI 13.4-17.1) and higher than revision rates following primary TKR (3.3%, 95% CI 3.1-3.5). Ninety-day mortality rates were lower after UKR compared with TKR (0.08% vs 0.33%) and lower than predicted had UKR patients received a TKR (0.18%), equivalent to 1 fewer death per 1000 cases. CONCLUSION: UKR revision rates were substantially higher than TKR even when demographics and caseload differences were accounted for; however, fewer deaths occur after UKR. This should be considered when forming treatment guidelines and commissioning services. Re-revision rates were similar between revised UKRs and TKRs, but considerably higher than for primary TKR, therefore UKR cannot be considered an intermediate procedure.

Predictive Factors for Revision and Survivorship Analysis of a Prevalent 36-mm Metal-on-Metal Total Hip Replacement System: A Large Single-Center Retrospective Cohort Study.

BACKGROUND: To our knowledge, this is the largest single-center cohort of the 36-mm Corail-Pinnacle metal-on-metal total hip replacements system, aiming to determine 10-year survivorship and identify predictors of revision. We further assessed year of implantation given reports of manufacturing variations affecting shells made after 2006 predisposing these components to increasing wear. METHODS: All Corail-Pinnacle 36-mm metal-on-metal hips implanted in a single center (2005-2012). The effect of patient and implant-related variables, and year of implantation on revision risk was assessed using Kaplan-Meier, Cox regression, and interrupted time series analysis. RESULTS: In total, 1212 metal-on-metal total hip replacements were implanted with a 10-year survival rate of 83.4% (95% confidence interval [CI] = 81.3-85.5). Mean follow-up duration was 7.3 years with 61% of patients reaching a minimum of 7 years of follow-up. One hundred nineteen patients required revision surgery (9.8%). Univariate analysis identified female gender (hazard ratio [HR] = 1.608, CI = 1.093-2.364, P = .016), age at implantation (HR = 0.982, CI = 0.968-0.997, P = .019), smaller 50-mm to 54-mm cup diameter (HR = 1.527, CI = 1.026-2.274, P = .037), and high-offset stems (HR = 2.573, CI = 1.619-4.089, P < .001) as predictors of revision. Multivariate modeling confirmed female gender and high-offset stems as significant predictors of revision. For components implanted after 2007, the number of revisions showed no statistically significant step increase compared to pre-2007 implantation. CONCLUSION: We observed a high 10-year failure rate (16.6%) with this implant, mostly due to adverse reaction to metal debris. Female gender and high femoral offset stems were significant predictors for all-cause revision. Year of implantation was not significantly associated with an increasing number of revisions from 2007 onwards, although further studies to validate the impact of manufacturing discrepancies are recommended.

Variation in timely surgery for hip fracture by day and time of presentation: a nationwide prospective cohort study from the National Hip Fracture Database for England, Wales and Northern Ireland.

BACKGROUND AND OBJECTIVE: Several studies report poorer quality healthcare for patients presenting at weekends. Our objective was to examine how timely surgery for patients with hip fracture varies with day and time of their presentation. METHODS: This population-based cohort study used 2017 data from the National Hip Fracture Database, which recorded all patients aged 60 years and over who presented with a hip fracture at a hospital in England, Wales and Northern Ireland. Provision of prompt surgery (surgery within 36 hours of presentation) was examined, using multivariable logistic regression with generalised estimating equations to derive adjusted risk ratios (RRs). Time was categorised into three 8-hour intervals (day: 08:00-15:59, evening: 16:00-23:59 and night: 00:00-07:59) for each day of the week. The model accounted for clustering by hospital and was adjusted by sex, age, fracture type, operation type, American Society of Anesthesiologists grade, preinjury mobility and location. RESULTS: We studied 68 977 patients from 177 hospitals. The average patient presenting during the day on Friday or Saturday was significantly less likely to undergo prompt surgery (Friday during 08:00-15:59, RR=0.93, 95% CI 0.91 to 0.96; Saturday during 08:00-15:59, RR=0.91, 95% CI 0.88 to 0.94) than patients in the comparative category (Thursday, during the day). Patients presenting during the evening (16:00-23:59) were consistently significantly less likely to undergo prompt surgery, and the effect was more marked on Fridays and Saturdays (Friday during 16:00-23:59, RR=0.83, 95% CI 0.80 to 0.85; Saturday during 16:00-23:59, RR=0.81, 95% CI 0.78 to 0.85). Patients presenting overnight (00:00-07:59), except on Saturdays, were significantly more likely to undergo surgery within 36 hours (RR>1.07). CONCLUSION: The provision of prompt hip fracture surgery was complex, with evidence of both an 'evening' and a 'night' effect. Investigation of weekly variation in hip fracture care is required to help implement strategies to reduce the variation in timely surgery throughout the entire week.

The Mid- to Long-Term Outcomes of the Lateral Domed Oxford Unicompartmental Knee Replacement: An Analysis From the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man.

BACKGROUND: Lateral unicompartmental knee replacement (UKR) is an alternative to total knee replacement for isolated lateral unicompartmental knee arthritis. The geometry and mechanics of the lateral compartment differ to the medial compartment with the Lateral Domed Oxford UKR designed to address this. We used the National Joint Registry (NJR) data to report the mid- to long-term outcomes of this device. METHODS: We performed a retrospective observational study using NJR data on 992 Lateral Domed Oxford UKRs implanted between 1st January 2005 and 31st December 2017. Outcomes of interest were implant survival and revision indications. RESULTS: The 10 year cumulative implant survival rates were 88.6% (CI 85.3-91.2). When compared with <55 year age group, the 55-64, 65-74 and ≥75 groups had significantly lower revision rates (hazard ratio (HR) = 0.56 (CI 0.32-0.98, P = .04), HR 0.40 (CI 0.22-0.72, P = .003), and HR 0.27 (CI 0.12-0.58, P = .001), respectively). The obese group had significantly (P = .04) increased revision risk compared with normal BMI (HR 2.33, CI 1.06-5.12). The commonest reasons for revision surgery were dislocation (n = 23, 2.3%), pain (n = 15, 1.5%), and aseptic loosening (n = 14, 1.4%). CONCLUSION: The Lateral Domed Oxford UKR provides a good option for isolated lateral compartment osteoarthritis. However, dislocation of the mobile bearing remains a problem, occurring in 2.3% of the patients and accounting for 30% of the revisions. To help prevent dislocation, it is now possible to assess bearing stability intraoperatively and if very unstable to implant a compatible fixed bearing tibial component, without the need for further bone preparation.

The effect of surgical approach in total hip replacement on outcomes: an analysis of 723,904 elective operations from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

BACKGROUND: Total hip replacement (THR) is clinically and cost-effective. The surgical approach employed influences the outcome; however, there is little generalisable and robust evidence to guide practice. METHODS: A total of 723,904 primary THRs captured in the National Joint Registry, linked to hospital inpatient, mortality and patient-reported outcome measures (PROMs) data with up to 13.75 years follow-up, were analysed. There were seven surgical approach groups: conventional posterior, lateral, anterior and trans-trochanteric groups and minimally invasive posterior, lateral and anterior. Survival methods were used to compare revision rates and 90-day mortality. Groups were compared using Cox proportional hazards and Flexible Parametric Survival Modelling (FPM). Confounders included age at surgery, sex, risk group (indications additional to osteoarthritis), American Society of Anesthesiologists grade, THR fixation, thromboprophylaxis, anaesthetic, body mass index (BMI) and deprivation. PROMs were analysed with regression modelling or non-parametric methods. RESULTS: Unadjusted analysis showed a higher revision risk than the referent conventional posterior for the conventional lateral, minimally invasive lateral, minimally invasive anterior and trans-trochanteric groups. This persisted with all adjusted FPM and adjusted Cox models, except in the Cox model including BMI where the higher revision rate only persisted for the conventional lateral approach (hazard rate ratio (HRR) 1.12 [95% CI 1.06,1.17] P < 0·001) and trans-trochanteric approaches (HRR 1.48 [95% CI 1.14,1.91] P = 0.003). PROMs demonstrated statistically, but not clinically, significant differences. Self-reported complications were more frequent with the conventional lateral approach, and the risk of 90-day mortality was higher (HRR 1.15 [95%CI 1.01-1.30] P = 0.029). CONCLUSIONS: Lateral approaches for THR are associated with worse outcomes, including more deaths and revisions, than the posterior approach. We recommend the posterior approach should be considered the current standard approach for THR. Large well-designed studies are needed to assess any potential benefits from using minimally invasive posterior approaches and the conventional anterior approach.

Is Aspirin as Effective as the Newer Direct Oral Anticoagulants for Venous Thromboembolism Prophylaxis After Total Hip and Knee Arthroplasty? An Analysis From the National Joint Registry for England, Wales, Northern Ireland, and the Isle of Man.

BACKGROUND: Few studies have compared aspirin with direct oral anticoagulants (DOACs) (DOACs = direct thrombin inhibitors and factor Xa inhibitors) for venous thromboembolism (VTE) prophylaxis after total hip arthroplasty (THA) and total knee arthroplasty (TKA). We assessed the efficacy and safety of aspirin compared with DOACs for VTE prophylaxis after THA and TKA using the world's largest joint arthroplasty registry. METHODS: We studied the National Joint Registry linked to English hospital inpatient episodes for 218,650 THA and TKA patients. Patients receiving aspirin were matched separately to patients receiving direct thrombin inhibitors and factor Xa inhibitors using propensity scores. Outcomes assessed at 90 days included VTE, length of stay, and adverse events. RESULTS: After THA, there was a significantly lower risk of VTE associated with the use of direct thrombin inhibitors (0.44%; odds ratio [OR], 0.69; 95% confidence interval [95% CI], 0.55-0.87; P = .002) and factor Xa inhibitors (0.37%; OR, 0.63; 95% CI, 0.47-0.85; P = .003) compared with aspirin (0.63%). After THA, direct thrombin inhibitors (coefficient, -0.37 days; 95% CI, -0.43 to -0.31; P < .001) and factor Xa inhibitors (coefficient, -0.80 days; 95% CI, -0.87 to -0.74; P < .001) were associated with a reduced length of stay compared with aspirin. Similar findings for both outcomes were observed after TKA. Compared with aspirin, DOACs were not associated with an increase in the risk of short-term revision surgery, reoperation, major hemorrhage, wound disruption, surgical site infection, and mortality. CONCLUSION: After THA and TKA, DOACs were associated with a reduced risk of VTE compared with aspirin. DOACs were associated with a reduced length of stay, and DOACs were not associated with an increase in the risk of further surgery, wound problems, bleeding complications, or mortality compared with aspirin.

A matched comparison of revision rates of cemented Oxford Unicompartmental Knee Replacements with Single and Twin Peg femoral components, based on data from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man.

Background and purpose - Registries report high revision rates after unicompartmental knee replacement (UKR) due, in part, to aseptic loosing. In an attempt to improve Oxford UKR femoral component fixation a new design was introduced with a Twin rather than a Single peg. We used the National Joint Registry (NJR) to compare the 5-year outcomes of the Single and Twin Peg cemented Oxford UKRs.Patients and methods - We performed a retrospective observational study using NJR data on propensity score matched Single and Twin Peg UKRs (matched for patient, implant and surgical factors). Data on 2,834 Single Peg and 2,834 Twin Peg were analyzed. Cumulative implant survival was calculated using the Kaplan-Meier method and comparisons between groups performed using Cox regression models.Results - In the matched cohort, the mean follow up for both Single and Twin Peg UKRs was 3.3 (SD 2) and 3.4 years (SD 2) respectively. The 5-year cumulative implant survival rates for Single Peg and Twin Peg were 94.8% (95% CI 93.6-95.8) and 96.2% (CI 95.1-97.1) respectively. Implant revision rates were statistically significantly lower in the Twin Peg (hazard ratio [HR)] = 0.74; p = 0.04). The revision rate for femoral component aseptic loosening decreased significantly (p = 0.03) from 0.4% (n = 11) with the Single Peg to 0.1% (n = 3) with the Twin Peg. The revision rate for pain decreased significantly (p = 0.01) from 0.8% (n = 23) with the Single Peg to 0.3% (n = 9) with the Twin Peg. No other reasons for revision had significant differences in revision rates.Interpretation - The revision rate for the cemented Twin Peg Oxford UKR was 26% less than the Single Peg Oxford UKR. This was mainly because the revision rates for femoral loosening and pain more than halved. This suggests that the Twin Peg component should be used in preference to the Single Peg design.