We investigated the revision rates of primary total hip replacement (THR) reported in the National Joint Registry (NJR) by types of bearing surfaces used. We analysed THR procedures across all orthopaedic units in England and Wales. Our analyses estimated all-cause and cause-specific revision rates. We identified primary THRs with heads and monobloc cups or modular acetabular component THRs with head and shell/liner combinations. We used flexible parametric survival models to estimate adjusted hazard ratios (HR). A total of 1,026,481 primary THRs performed between 2003–2019 are included in the primary analysis (Monobloc: n=378,979 and Modular: n=647,502) with 20,869 (2%) of these primary THRs subsequently undergoing a revision episode (Monobloc: n=7,381 and Modular: n=13,488). Compared to implants with a cobalt chrome head and highly crosslinked polyethylene (HCLPE) cup, the all-cause risk of revision for monobloc acetabular implant was higher for patients with cobalt chrome or stainless steel head and non-HCLPE cup. The risk of revision was lower for patients with a delta ceramic head and HCLPE cup implant, at any post-operative period. Compared to patients with a cobalt chrome head and HCLPE liner primary THR, the all-cause risk of revision for modular acetabular implant varied non-constantly. THRs with a delta ceramic or oxidised zirconium head and HCLPE liner had a lower risk of revision throughout the entire post-operative period. The all-cause and indication-specific risk of prosthesis revision, at different time points following the initial implantation, is lower for implants with a delta ceramic or oxidised zirconium head and a HCLPE liner/cup than commonly used alternatives such as cobalt chrome heads and HCLPE liner/cup.
Hip bearing surfaces materials are typically broadly reported in national registry (metal-on-polyethylene, ceramic-on-ceramic etc). We investigated the revision rates of primary total hip replacement (THR) reported in the National Joint Registry (NJR) by detailed types of bearing surfaces used. We analysed THR procedures across all orthopaedic units in England and Wales. Our analyses estimated all-cause and cause-specific revision rates. We identified primary THRs with heads and monobloc cups or modular acetabular component THRs with detailed head and shell/liner bearing material combinations. We used flexible parametric survival models to estimate adjusted hazard ratios (HR). A total of 1,026,481 primary THRs performed between 2003–2019 were included in the primary analysis (Monobloc cups: n=378,979 and Modular cups: n=647,502) with 20,869 (2%) of these primary THRs subsequently undergoing a revision episode (Monobloc: n=7,381 and Modular: n=13,488). Compared to implants with a cobalt chrome head and highly crosslinked polyethylene (HCLPE) cup, the overall risk of revision for monobloc acetabular implant was higher for patients with cobalt chrome or stainless steel head and non-HCLPE cup. The risk of revision was lower for patients with a delta ceramic head and HCLPE cup implant, at any post-operative period. Compared to patients with a cobalt chrome head and HCLPE liner primary THR, the overall risk of revision for modular acetabular implant varied non-constantly. THRs with a delta ceramic or oxidised zirconium head and HCLPE liner had a lower risk of revision throughout the entire post-operative period. The overall and indication-specific risk of prosthesis revision, at different time points following the initial implantation, is reduced for implants with a delta ceramic or oxidised zirconium head and a HCLPE liner/cup in reference to THRs with a cobalt chrome head and HCLPE liner/cup.
Implants in total hip replacement (THR) are associated with different clinical and cost-effectiveness profiles,. We estimate the costs and outcomes for NHS patients in the year after THR associated with implant bearing materials using linked routinely collected data. We linked NJR primary elective THR patients for osteoarthritis to HES and National PROMs. We estimated health care costs, health-related quality of life indices, and revision risks, in the year after primary and revision THRs overall. We used generalised linear models adjusting for patient and hospital characteristics and estimated 10-year cumulative probability of revision. We imputed utilities using chained equations for half the sample with missing PROMS. We linked 577,973 elective primary THRs and 11,812 subsequent revisions. One year after primary THR, patients with the cemented THRs using cobalt chrome or stainless steel head with HCLPE liner/cup cost the NHS, on average, £13,101 (95%CI £13,080,£13,122), had an average quality-of-life score of 0.788 (95%CI 0.787,0.788), and a 10-year revision probability of 1.9% (95%CI 1.6,2.3). Compared to the reference, patients receiving a cemented THR with delta ceramic head and HCLPE liner/cup, hybrid THR with delta ceramic head and HCLPE liner/cup, and hybrid THR with alumina head and HCLPE liner/cup had lower 1-year costs (-£572 \[95% CI -£775,-£385\], -£346 \[-£501,-£192\], -£371 \[-£574,-£168\] respectively), better quality of life (0.007 \[95% CI 0.003,0.011\], 0.013 \[0.010,0.016\], 0.009 \[0.005,0.013\] respectively), and lower 10-year revision probabilities (1.4% \[1.03,2.0\], 1.5 \[1.3,1.7\], 1.6%\[1.2,2.1\] respectively). Implant bearing materials are associated with varying mean costs and health outcomes after primary THR. Ours is the first study to derive costs and health outcomes from large, linked databases using multiple imputation methods to deal with bias. Our findings are useful for commissioning and procurement decisions and to inform a subsequent cost-effectiveness model with more granular detail on THR implant types.
Prosthetic implants used in primary total hip replacements have a range of bearing surface combinations (metal-on-polyethylene, ceramic-on-polyethylene, ceramic-on-ceramic, metal-on-metal); head sizes (small <36mm, large 36mm+); and fixation techniques (cemented, uncemented, hybrid, reverse hybrid), which influence prosthesis survival, patient quality of life, and healthcare costs. This study compared the lifetime cost-effectiveness of implants to determine the optimal choice for patients of different age and gender profiles. In an economic decision Markov model, the probability that patients required one or more revision surgeries was estimated from analyses of UK and Swedish hip joint registries, for males and females aged <55, 55–64, 65–74, 75–84, and 85+ years. Implant and healthcare costs were estimated from hospital procurement prices, national tariffs, and the literature. Quality-adjusted life years were calculated using utility estimates, taken from Patient-Reported Outcome Measures data for hip procedures in the UK.Background
Methods
Inpatient physiotherapy is routinely provided after total knee replacement (TKR) surgery to enhance recovery prior to discharge. However, the provision of outpatient physiotherapy is variable in the UK, and the longer-term benefits of outpatient physiotherapy are unclear. This study aimed to evaluate the feasibility of conducting a randomised controlled trial (RCT) to assess the effectiveness and cost-effectiveness of group-based outpatient physiotherapy after TKR. Patients listed for primary TKR were recruited prior to surgery. Patients who decided not to participate were asked about their reasons for non-participation. Patients were randomised to attend a newly developed post-operative physiotherapy class plus usual care or usual care alone. Patients allocated to the intervention group were invited to attend a weekly one-hour physiotherapy class, starting at 6 weeks after surgery and running over 6 consecutive weeks. The group classes were run by two physiotherapists within an outpatient gym, and involved task-orientated and individualised exercises. Classes ran on a rolling system, allowing new patients to join each week. Participants completed an evaluation questionnaire after the final class. Outcomes assessment was by questionnaire prior to surgery and 2 weeks, 3 months and 6 months after surgery. Outcomes related to function, pain, balance, self-efficacy, participation, quality of life and resource use.Background
Methods
Total hip replacement (THR) and total knee replacement (TKR) are usually effective at relieving pain; however, 7–23% of patients experience chronic post-surgical pain. These trials aimed to investigate the effect of local anaesthetic wound infiltration on pain severity at 12 months after primary THR or TKR for osteoarthritis. Between November 2009 and February 2012, 322 patients listed for THR and 316 listed for TKR were recruited into a single-centre double-blind randomised controlled trial. Participants were randomly assigned (1:1) to receive local anaesthetic infiltration and standard care or standard care alone. Participants and outcomes assessors were masked to group allocation. The primary outcome was pain severity on the WOMAC Pain scale at 12 months post-surgery. Analyses were conducted using intention-to-treat and per-protocol approaches. Ethics approval was obtained from Southampton and South West Hampshire Research Ethics Committee.Background
Methods
Total hip replacement (THR) is a common elective surgical procedure and can be effective for reducing chronic pain. However, waiting times for THR can be considerable, and patients often experience significant pain during this time. A pain self-management intervention may provide patients with the skills to enable them to manage their pain and its impact more effectively before surgery. However, studies of arthritis self-management programmes have faced challenges because of low recruitment rates, poor intervention uptake, and high attrition rates. This study aimed to evaluate the feasibility of a randomised controlled trial (RCT) to assess the effectiveness and cost-effectiveness of a group-based pain self-management course for patients undergoing THR. Specific objectives were to assess trial design, ascertain recruitment and retention rates, identify barriers to participation, refine data collection methods, and evaluate uptake and patient satisfaction with the course. Patients listed for THR in an elective orthopaedic centre Bristol, UK were sent a postal invitation about the study. Participants were randomised to attend a pain self-management course plus standard care or standard care only using a computer-generated randomisation system. The pain self-management course was delivered by Arthritis Care and consisted of two half-day group sessions prior to surgery and one full-day group session 2–4 months after surgery. A structured course evaluation questionnaire was completed by participants. Outcomes assessment was by postal questionnaire prior to surgery and 1-month, 3-months and 6-months after surgery. Self-report resource use data were collected using a diary prior to surgery and inclusion of resource use questions in the 3-month and 6-month post-operative questionnaires. Brief telephone interviews were conducted with non-participants to explore barriers to participation. Postal invitations were sent to 385 eligible patients and 88 patients consented to participate (23% recruitment rate). Participants had a mean age of 66 years and 65% were female. Brief interviews with 57 non-participants revealed the most common reasons for non-participation were perceptions about the intervention and difficulties in getting to the hospital for the course. Of the 43 patients randomised to the intervention group, 28 attended the pre-operative pain self-management sessions and 11 attended the post-operative sessions. Participant satisfaction with the course was high, and patients enjoyed the group format. Retention of participants was acceptable, with 83% completing follow-up. Questionnaire return rates were high (76–93%), with the exception of the pre-operative resource use diary (35%). Completion rates for the resource use questions varied by category and allowed for an economic perspective from the health and social care payer to be taken. Undertaking feasibility work for a RCT is labour-intensive; however this study highlights the importance of conducting such work. Postal recruitment resulted in a low recruitment rate and brief interviews with non-participants provided valuable information on barriers to participation. Embedding collection of resource use data within questionnaires resulted in higher completion rates than using resource use diaries. While patients who attended the course gave positive feedback, attendance was low. Findings from this feasibility study enable us to design successful definitive group-based RCTs in the future.
Robust evidence on the effectiveness of peri-operative local anaesthetic infiltration (LAI) is required before it is incorporated into the pain management regimen for patients receiving total knee replacement (TKR). To assess the effectiveness of peri-operative LAI for pain management in patients receiving TKR we conducted a systematic review, fully powered randomised controlled trial (RCT) and economic evaluation. We searched MEDLINE, Embase and Cochrane databases for RCTs of peri-operative LAI in patients receiving TKR. Two reviewers screened abstracts and extracted data. Outcomes were pain, opioid use, mobilisation, hospital stay and complications. Authors were contacted if required. When feasible, we conducted meta-analysis with studies analysed separately if a femoral nerve block (FNB) was provided. In the APEX RCT, we randomised 316 patients awaiting TKR to standard anaesthesia which included FNB, or to the same regimen with additional peri-operative LAI (60mls 0.25% bupivacaine plus adrenaline). Post-operatively, all patients received patient-controlled morphine. The primary outcome was joint pain severity (WOMAC-Pain) at 12 months. Patients and outcome assessors were blinded to allocation. Within APEX, cost-effectiveness was assessed from the health and social-care perspective in relation to quality adjusted life years (QALYs) and WOMAC-Pain at 12-months. Resource use was collected from hospital records and patient questionnaires. In the systematic review, 23 studies including 1,439 patients were identified. Compared with patients receiving no intervention, LAI reduced WOMAC-Pain by standardised mean difference (SMD) −0.40 (95%CI −0.58, −0.22; p<0.001) at 24 hours at rest and by SMD −0.27 (95%CI −0.50, −0.05; p=0.018) at 48 hours during activity. In three studies there was no difference in pain at any time point between randomised groups where all patients received FNB. Patients receiving LAI spent fewer days in hospital, used less opioids and mobilised earlier. Complications were similar between groups. Few studies reported long-term outcomes. In the APEX RCT, pain levels in hospital were broadly similar between groups. Overall opioid use was similar between groups. Time to mobilisation and discharge were largely dependent on local protocols and did not differ between groups. There were no differences in pain outcomes between groups at 12 months. In the economic evaluation, LAI was marginally associated with lower costs. Using the NICE £20,000 per QALY threshold, the incremental net monetary benefit was £264 (95%CI, −£710, £1,238) and the probability of being cost-effective was 62%. Although LAI appeared to have some benefit for reduced pain in hospital after TKR there was no evidence of pain control additional to that provided by femoral nerve block, however it would be cost-effective at the current NICE thresholds.
Robust evidence on the effectiveness of peri-operative local anaesthetic infiltration (LAI) is required before it is incorporated into the pain management regimen for patients receiving total hip replacement (THR). We assessed the effectiveness of LAI using a systematic review and a fully powered randomised controlled trial (RCT) with economic evaluation. We searched MEDLINE, Embase and Cochrane databases for RCTs of peri-operative LAI in patients receiving THR. Two reviewers screened abstracts, extracted data, and liaised with authors. Outcomes were pain, opioid use, mobilisation, hospital stay and complications. If feasible, we conducted meta-analysis. In the APEX RCT, we randomised 322 patients awaiting THR to receive additional peri-operative LAI (60mls 0.25% bupivacaine plus adrenaline) or standard anaesthesia alone. Post-operatively, all patients received patient-controlled morphine. The primary outcome was joint pain severity (WOMAC-Pain) at 12 months. Patients and outcome assessors were blinded to allocation. Within APEX, cost-effectiveness was assessed from the health and social-care perspective in relation to quality adjusted life years (QALYs) and WOMAC-Pain at 12-months. Resource use was collected from hospital records and patient questionnaires. In the systematic review, we identified 13 studies (909 patients). Patients undergoing THR receiving LAI experienced greater pain reduction at 24 hours at rest, standardised mean difference (SMD) −0.61 (95%CI −1.05, −0.16; p=0.008) and at 48 hours during activity, SMD −0.43 (95%CI −0.78, −0.09; p=0.014). Patients receiving LAI spent fewer days in hospital, used less opioids and mobilised earlier. Complications were similar between groups. Long-term outcomes were not a focus of these studies. In the APEX RCT, pain levels in hospital were broadly similar between groups, probably due to patient-controlled analgesia. Opioid use was similar between groups. Time to mobilisation and discharge were largely dependent on local protocols and did not differ between groups. Patients receiving LAI were less likely to report severe pain at 12 months than those receiving standard care, odds ratio 10.2 (95%CI 2.1, 49.6; p=0.004). Complications were similar between groups. In the economic evaluation, LAI was associated with lower costs and greater cost-effectiveness than standard care. Using a £20,000 per QALY threshold, the incremental net monetary benefit was £1,125 (95%CI £183, £2,067) and the probability of being cost-effective was greater than 98 %. The evidence suggests that peri-operative LAI is a cost-effective intervention for reducing acute and chronic post-surgical pain after THR.
