Hip prosthetic joint infection (PJI) is a debilitating complication following joint replacement surgery, with significant impact on patients and healthcare systems. The INFection ORthopaedic Management: Evidence into Practice (INFORM: EP) study, builds upon the 6-year INFORM programme by developing evidence-based guidelines for the identification and management of hip PJI. A panel of 21 expert stakeholders collaborated to develop best practice guidelines based on evidence from the previous INFORM research programme. An expert consensus process was used to refine guidelines using RAND/UCLA criteria. The guidelines were then implemented over a 12-month period through a Learning Collaborative of 24 healthcare professionals from 12 orthopaedic centres in England. Qualitative interviews were conducted with 17 members of the collaborative and findings used to inform the development of an implementation support toolkit. Patient and public involvement contextualised the implementation of the guidelines. The study is registered with the ISCRTN (34710385).Introduction
Methods
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.
Hip prosthetic joint infection (PJI) is a debilitating complication following joint replacement surgery, with significant impact on patients and healthcare systems. The INFection ORthopaedic Management: Evidence into Practice (INFORM:EP) study, builds upon the 6-year INFORM programme by developing evidence-based guidelines for the identification and management of hip PJI. A panel of 21 expert stakeholders collaborated to develop best practice guidelines based on evidence from INFORM \[1\]. An expert consensus process was used to refine guidelines using RAND/UCLA criteria. The guidelines were then implemented over a 12-month period through a Learning Collaborative of 24 healthcare professionals from 12 orthopaedic centres in England. Qualitative interviews were conducted with 17 members of the collaborative and findings used to inform the development of an implementation support toolkit. Patient and public involvement contextualised the implementation of the guidelines. The study is registered with the ISCRTN (34710385). The INFORM guidelines, structured around the stages of PJI management, were largely supported by surgeons, although barriers included limited awareness among non-surgical team members, lack of job planning for multidisciplinary teams, and challenges in ensuring timely referrals from primary care. Psychological support for patients was identified as a critical gap. Advanced Nurse Practitioners and multidisciplinary team (MDT) coordinators were seen as potential bridges to address these knowledge gaps. The guidelines were also viewed as a useful tool for service development. This study presents the first evidence-based guidelines for hip PJI management, offering a comprehensive approach to prevention, treatment, and postoperative care. Effective implementation is crucial, involving wider dissemination amongst primary and community care, as well as non-specialist treatment centres. Further resources are needed to ensure job planning for MDTs and psychological support for patients. Overall, this study lays the foundation for improved PJI management, benefiting patients and healthcare systems.
Approximately 15–20% of patients report chronic pain three months after total knee replacement (TKR). The STAR care pathway is a clinically important and cost-effective personalised intervention for patients with pain 3 months after TKR. The pathway comprises screening, assesment, onward referral for treatment and follow-up over one year. In a multicentre randomised controlled trial comparing the pathway with usual care, the pathway improved pain at 6 and 12 months. This study examined the longer-term clinical and cost-effectiveness of the STAR care pathway. STAR trial participants were followed-up at a median of 4 years post-randomisation. Co-primary outcomes were self-reported pain severity and interference in the replaced knee, assessed with the Brief Pain Inventory (BPI). Resource use from electronic hospital records was valued with UK reference costs.Abstract
Introduction
Methodology
Periprosthetic joint infections (PJIs) are uncommon but are devastating complications of total knee replacement (TKR). We analysed the risk factors of revision for PJI following primary TKR and their association with PJI at different post-operative periods. Primary TKRs and subsequent revision surgeries performed for PJI from 2003–2014 were identified from the National Joint Registry (NJR). Multilevel piece-wise exponential non-proportional hazards models were used to estimate the effect of the investigated factors at different post-operative periods. Patient, perioperative and healthcare system characteristics were investigated and data from the Hospital Episode Statistics for England were linked to obtain information on specific comorbidities. The index TKRs consisted of 679,010 primaries with 3,659 subsequently revised for PJI, 7% within 3 months, 6% between 3–6months, 17% between 6–12months, 27% between 1–2years and 43% ≥2 years from the index procedure. Risk factors for revision for PJI included male sex, high BMI, high ASA grade and young age. Patients with chronic pulmonary disease, diabetes and liver disease had higher risk of revision for PJI, as had patients who had a primary TKR for an indication of trauma or inflammatory arthropathy. Surgical procedure, fixation method, constraint and bearing type influenced the risk of revision for PJI. Their effects were period-specific. No or small associations were found with the operating surgeon grade, surgical volume and hospital surgical volume. These findings from the world's largest joint replacement registry show a more complex picture than the meta-analyses published to date with specific time-dependent effects for the identified risk factors.
Prosthetic joint infection (PJI) is an uncommon but serious complication of hip replacement. A recent systematic review of patient risk factors for PJI identified male gender, smoking status, increasing BMI, steroid use, previous joint surgery and comorbidities of diabetes, rheumatoid arthritis and depression as risk factors for developing PJI. Limitations of the current literature include the short term follow up of most published studies. We investigated the role of patient, surgical and healthcare factors on the risk of revision of a primary hip replacement for PJI at different time-points in the post-operative follow-up. It is important that those risk factors are identified so that patients can be appropriately counselled according to their individual risk profile prior to surgery and modifiable factors can be addressed to reduce the risk of PJI at an individual and healthcare system level. Primary hip replacements and subsequent revision procedures performed for PJI from 2003–2014 were identified from the National Joint Registry (NJR). Patient (age, gender, ASA grade, BMI), perioperative (surgical indication, type of anaesthesia, thromboprophylaxis regime, surgical approach, hip replacement and bearing surface and use of femoral or acetabular bone graft) and healthcare system characteristics (surgeon grade, surgical volume) were linked with data from Hospital Episode Statistics to obtain information on specific ethnicity and comorbidities (derived from the Charlson index). Multilevel piecewise exponential non-proportional hazards models were used to estimate their effects at different post-operative periods (0–3 months, 3–6 months, 6–12 months, 12–24 and >24 months post-operation).Introduction
Materials and Methods
To aid recovery, rehabilitation is an important adjunct to surgery. Acknowledging the MRC framework for complex interventions we assessed the evidence-base for components of comprehensive rehabilitation in total hip (THR) and total knee replacement (TKR) pathways. We conducted systematic reviews and meta-analyses of randomised controlled trials (RCT) of pre-surgical exercise and education, occupational therapy and post-operative physiotherapy. In feasibility RCTs we explored acceptability of pain self-management and occupational therapy before THR, and physiotherapy after TKR. We searched trial registers for ongoing RCTs.Background
Methods
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
Chronic pain after joint replacement is common, affecting approximately 10% of patients after total hip replacement (THR) and 20% of patients after total knee replacement (TKR). Heightened generalised sensitivity to nociceptive input could be a risk factor for the development of this pain. The primary aim of this study was to investigate whether preoperative widespread pain sensitivity was associated with chronic pain after joint replacement. Data were analysed from 254 patients receiving THR and 239 patients receiving TKR. Pain was assessed preoperatively and at 12 months after surgery using the Western Ontario and McMaster Universities Osteoarthritis Pain Scale. Preoperative widespread pain sensitivity was assessed through measurement of pressure pain thresholds (PPTs) at the forearm using an algometer. Statistical analysis was conducted using linear regression and linear mixed models, and adjustments were made for confounding variables.Background
Methods
In the UK, over 160,000 total joint replacements are performed annually. About 1% of patients subsequently develop a deep bacterial infection and, if untreated, this can result in severe pain, disability, and death. Costs to the NHS are substantial. The INFORM (Infection Orthopaedic Management) programme aims to address gaps in knowledge relating to treatment of deep prosthetic joint infection through six work packages. The programme is supported by a patient forum and patient-partners working on oversight groups. Literature reviews and meta-analysis of individual patient data from cohort studies of patients treated for prosthetic hip infection. Analysis of the National Joint Registry to observe trends in infection rates, and identify risk markers for infection and effective treatments. Qualitative interviews with patients and health professionals exploring the impact of infection and its treatment. A multicentre randomised controlled trial to compare patient-centred outcomes after one- or two-stage revision for prosthetic hip infection. An economic evaluation to assess cost-effectiveness of treatments. A survey of patients to explore individuals’ preferences for treatments.Background
Methods
There is limited information about the extent to which the association between pre-operative and chronic post-operative pain is mediated via pain-on-movement or pain-at-rest. We explored these associations in patients undergoing total hip (THR) and total knee (TKR) replacement. 322 and 316 patients receiving THR and TKR respectively were recruited into in a single centre UK cohort (APEX) study. Pre-operative, acute post-operative and 12-month pain severity was measured using self-reported pain instruments. The association between pre-operative / acute pain and chronic post-operative pain was investigated using structural equation modelling (SEM).Objective
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
The two-stage revision strategy has been claimed as being the “gold standard” for treating prosthetic joint infection. The one-stage revision strategy remains an attractive alternative option, however, its effectiveness in comparison to the two-stage strategy remains uncertain. A systematic review and meta-analysis was conducted to compare the effectiveness of one- and two-stage revision strategies to prevent re-infection after prosthetic hip infection. Cohort studies (prospective or retrospective) conducted in unselected patients with infection treated exclusively by one- or two-stage revision and reporting re-infection outcomes within two years of revision were retrieved from MEDLINE, EMBASE, Web of Science, Cochrane databases, manual search of bibliographies to March 2015, and email contact with investigators. Data were extracted by two independent investigators and a consensus was reached with involvement of a third. Rates of re-infection were aggregated using random-effect models after arcsine transformation, and were grouped by study and population level characteristics.Background
Methods
Joint arthroplasty is a common surgical procedure, with over 185,000 primary hip and knee arthroplasties performed in England, Wales and Northern Ireland in 2014. After total hip or knee arthroplasty, about 1% of patients develop deep prosthetic joint infection (PJI), which usually requires further major operations to clear the infection. Although PJI affects only a small percentage of patients it is one of the most devastating complications associated with this procedure. Research evidence has focussed on clinical effectiveness of revision surgery while there has been less focus on the impact on patients and support needs. Using a systematic review approach, the aim of this study was to assess support needs and evaluate what interventions are routinely offered to support patients undergoing treatment for PJI following hip or knee arthroplasty. We systematically searched MEDLINE, Embase, Web of Science, PsycINFO, Cinahl, Social Science Citation Index, and The Cochrane Library from 1980 to February 15, 2015 for observational (prospective cohort, nested case-control, case-control, and retrospective cohort) studies, qualitative studies, and clinical trials that report on the support needs and interventions for patients being treated for PJI or other major adverse occurrences following joint arthroplasty. Data were extracted by two independent investigators and consensus reached with involvement of a third. Of 4,161 potentially relevant citations, we identified one case-control, one prospective cohort and two qualitative studies for inclusion in the synthesis. Patients report that PJI and treatment had a profoundly negative impact affecting physical, emotional, social and economic aspects of their lives. No study evaluated support interventions for PJI or other major adverse occurrences following hip and knee arthroplasty. The interpretation of study results is limited by variation in study design, outcome measures and the small number of relevant eligible studies. Findings show that patients undergoing treatment for PJI have extensive physical, psychological, social and economic support needs. Our review highlights a lack of evidence about support strategies for patients undergoing treatment for PJI and other adverse occurrences. There is a need to design, implement and evaluate interventions to support these patients.
Prosthetic joint infection (PJI) is an uncommon but serious complication of hip and knee replacement. We investigated the rates of revision surgery for the treatment of PJI following primary and revision hip and knee replacement, explored time trends, and estimated the overall surgical burden created by PJI. We analysed the National Joint Registry for England and Wales for revision hip and knee replacements performed for a diagnosis of PJI and their index procedures from 2003–2014. The index hip replacements consisted of 623,253 primary and 63,222 aseptic revision hip replacements with 7,642 revisions subsequently performed for PJI; for knee replacements the figures were 679,010 primary and 33,920 aseptic revision knee replacements with 8,031 revisions subsequently performed for PJI. Cumulative incidence functions, prevalence rates and the burden of PJI in terms of total procedures performed as a result of PJI were calculated. Revision rates for PJI equated to 43 out of every 10,000 primary hip replacements (2,705/623,253), i.e. 0.43%(95%CI 0.42–0.45), subsequently being revised due to PJI. Around 158 out of every 10,000 aseptic revision hip replacements performed were subsequently revised for PJI (997/63,222), i.e. 1.58%(1.48–1.67). For knees, the respective rates were 0.54%(0.52–0.56) for primary replacements, i.e. 54 out of every 10,000 primary replacements performed (3,659/679,010) and 2.11%(1.96–2.23) for aseptic revision replacements, i.e. 211 out of every 10,000 aseptic revision replacements performed (717/33,920). Between 2005 and 2013, the risk of revision for PJI in the 3 months following primary hip replacement rose by 2.29 fold (1.28–4.08) and after aseptic revision by 3.00 fold (1.06–8.51); for knees, it rose by 2.46 fold (1.15–5.25) after primary replacement and 7.47 fold (1.00–56.12) after aseptic revision. The rates of revision for PJI performed at any time beyond 3 months from the index surgery remained stable or decreased over time. From a patient perspective, after accounting for the competing risk of revision for an aseptic indication and death, the 10-year cumulative incidence of revision hip replacement for PJI was 0.62%(95%CI 0.59–0.65) following primary and 2.25%(2.08–2.43) following aseptic revision; for knees, the figures were 0.75%(0.72–0.78) following primary replacement and 3.13%(2.81–3.49) following aseptic revision. At a health service level, the absolute number of procedures performed as a consequence of hip PJI increased from 387 in 2005 to 1,013 in 2014, i.e. a relative increase of 2.6 fold. While 70% of those revisions were two-stage, the use of single stage revision increased from 17.6% in 2005 to 38.5% in 2014. For knees, the burden of PJI increased by 2.8 fold between 2005 and 2014. Overall, 74% of revisions were two-stage with an increase in use of single stage from 10.0% in 2005 to 29.0% in 2014. Although the risk of revision due to PJI following hip or knee replacement is low, it is rising. Given the burden and costs associated with performing revision joint replacement for prosthetic joint infection and the predicted increased incidence of both primary and revision hip replacement, this has substantial implications for service delivery.
Around 1% of the 185,000 primary hip and knee arthroplasties performed in the UK are followed by prosthetic joint infection (PJI). Although PJI affects a small percentage of patients, it is one of the most devastating complications associated with this procedure. Treatment usually involves further major surgery which can adversely affect patients' quality of life. Understanding current service provision provides valuable information needed to design and evaluate support interventions for patients. The aim of this survey was to identify usual care pathways and support in UK NHS orthopaedic centres for this population. The 20 highestvolume UK NHS orthopaedic centresfor hip and knee arthroplasty account for 33–50% of all cases treated for prosthetic joint infection. Infection leads at each centre were invited to participate in a survey about usual care provision and support for PJI. Questions exploredfollow up time-points; use of standard outcome measures; multidisciplinary care plans; supportive in-patient care and care after treatment; and onward referrals. Survey responses were recorded on a standardised proforma. Data were entered into Excel for analysis, then reviewed and coded into categories and frequency statistics to describe categorical data. A descriptive summary was developed based on these categories. Eleven of the highestvolume orthopaedic centres completed the survey. Follow-up of patients varied greatly across centres; some centres reviewed patients at weekly or 2 week intervals, while all centres saw patients at 6 weeks. Long-term follow-up varied across centres from 3–4 monthsto 12 monthly. Length of follow-up period varied from until the infection had cleared toindefinitely. Follow-up timepoints were only standardised in 4 out of 11 centres. Only 1 centre had a dedicated infection clinic. Advice on who patients should contact if they had concerns included the consultant, community nurse, extended scope practitioner or the ward, while 3 centres told patients to avoid calling their GP. Only half of the centres routinely used standardised outcome measures with patients with PJI. The majority of centres provided standard physiotherapy and occupational therapy (OT) to in-patients while approximately half also offered social support. Only one centre provided dedicated physiotherapy and OT on a separate infection ward. Three centres provided hospital at home or community services to patients in-between operative stages. Only 3 out of 11 centres stated they had specific multidisciplinary care plans in place for patients. Once discharged most patients were provided with physiotherapy, OT and social services if needed. Common barriersto referral included complexities of referring patients outside the hospital catchment area;lack of availability of community services, and shortage of staff including physiotherapists. Delays in rehab and social services could also be problematic. Findings show wide variation intreatment pathways and support for patients treated for PJI, both as inpatients and in the community. Only one of the 11 centreswho participated had a dedicated infection clinic. Only one centre suggested they individualised their physiotherapy support. A number of barriers exist to referring patients on to other support services after revision surgery.
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.
The mini-incision posterior approach may appeal to surgeons comfortable with the standard posterior approach to the hip. We present the first systematic review and meta-analysis of these two approaches. Twelve randomised controlled trials and four non-randomised trials comprising of 1498 total hip arthroplasties were included. The mini-incision posterior approach was associated with an early improvement in Harris hip score of 1.8 points (P < 0.001), reduced operating time (5 minutes, P < 0.001), length of hospital stay (14 hours, P < 0.001), intraoperative and total blood loss (63 ml, P < 0.001 and 119 ml, P < 0.001 respectively). There were no statistically significant differences on the incidence of dislocation, nerve injury, infection or venous thromboembolic events. The minimally invasive posterior approach appears to provide a safe and acceptable alternative to the standard incision posterior approach.
