Primary care consultations and pain medicine prescriptions: a comparison between patients with and without chronic pain after total knee replacement

BACKGROUND: Approximately 20% of patients experience chronic pain after total knee replacement (TKR). The impact of chronic pain after TKR on primary care services in the UK is currently unknown. The aim of this study was to compare primary care consultations and pain medicine prescriptions between patients with and without chronic pain after TKR. METHODS: Data from 5,055 patients who received TKR between 2009 and 2016 with anonymised linked data from the Clinical Practice Research Datalink Gold (CPRD) and English Hospital Episode Statistics (HES) Patient Reported Outcome Measures (PROMs) programme were analysed. The exposure time was from 10 years pre-operative to eight years post-operative. Patients with a score ≤ 14 on the Oxford Knee Score pain component scale at 6 months post-operative were classified as having chronic pain after TKR. Primary care consultations and prescribed pain medicines were quantified, and costs calculated based on national cost data. RESULTS: 721 patients (14%) had chronic pain after TKR. The prevalence and costs of primary care consultations and pain medicine prescriptions per year were consistently higher for patients with chronic pain after TKR compared with those without chronic pain after TKR; these differences were observed both before and after surgery. There was a substantial and sustained increase in the cost of opioid prescriptions after surgery for patients with chronic pain after TKR, peaking at seven years post-operative. CONCLUSIONS: Increased primary care consultations and pain medicine prescriptions associated with chronic pain after TKR represent a considerable financial cost to primary care services. Evaluation of interventions to reduce the risk of developing this pain condition and improve the early management of pain after TKR are needed to improve outcomes for patients and reduce costs to healthcare services. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-022-05492-6

Post-operative determinants of chronic pain after primary knee replacement surgery:Analysis of data on 258,386 patients from the National Joint Registry for England, Wales, Northern Ireland and the Isle of Man (NJR)

Objective: To identify post-operative risk factors for the development of chronic pain after knee replacement. Design: Primary knee replacements in persons aged ≥18 years between April 2008 and December 2016 from the National Joint Registry, linked with English Hospital Episode Statistics data, and Patient Reported Outcome Measures. The outcome was chronic pain 6-months after surgery (Oxford Knee pain score). Logistic regression modelling identified risk factors for chronic pain outcome. Results: 258,386 patients; 56.7% women; average age 70.1 years (SD ​± ​8.8 years). 43,702 (16.9%) were identified as having chronic pain 6-months post-surgery. Within 3 months of surgery complications were uncommon: intra-operative complications 1224 (0.5%); ≥1 medical complication 6073 (2.4%)); 32,930 (12.7%) hospital readmissions; 3848 (1.5%) re-operation; 835 (0.3%) revision. Post-surgical risk factors of chronic pain were: mechanical complication of prosthesis odds ratio (OR) 1.56 (95% Confidence Interval 1.35, 1.80); surgical site infection OR 1.13 (0.99, 1.29); readmission OR 1.47 (1.42, 1.52); re-operation OR 1.39 (1.27, 1.51); revision OR 1.92 (1.64, 2.25); length of stay e.g. 6+ vs. <2 days OR 1.48 (1.35, 1.63), blood transfusion OR 0.47 (0.26, 0.86) and myocardial infarction OR 0.69 (0.49, 0.97). Discriminatory ability of the model was only fair (c-statistic 0.71) indicating that post-surgical predictors explain a limited amount of variability in chronic pain. Conclusions: We identified a number of post-operative factors relating to the operation and early recovery that are associated with chronic pain following primary knee replacement. The model had weak discriminatory ability indicating that there remains considerable unexplained variability in chronic pain outcome

UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE): what does analysis of linked, routinely collected national datasets tell us about mid-late term revision risk after knee replacement?

OBJECTIVE: To identify patients at risk of mid-late term revision of knee replacement (KR) to inform targeted follow-up. DESIGN: Analysis of linked national datasets from primary and secondary care (Clinical Practice Research Datalink (CPRD GOLD), National Joint Registry (NJR), English Hospital Episode Statistics (HES) and Patient Reported Outcome Measures (PROMs)). PARTICIPANTS: Primary elective KRs aged ≥18 years. EVENT OF INTEREST: Revision surgery ≥5 years (mid-late term) postprimary KR. STATISTICAL METHODS: Cox regression modelling to ascertain risk factors of mid-late term revision. HRs and 95% CIs assessed association of sociodemographic factors, comorbidities, medication, surgical variables and PROMs with mid-late term revision. RESULTS: NJR-HES-PROMs data were available from 2008 to 2011 on 188 509 KR. CPRD GOLD-HES data covered 1995-2011 on 17 378 KR. Patients had minimum 5 years postprimary surgery to end 2016. Age and gender distribution were similar across datasets; mean age 70 years, 57% female. In NJR, there were 8607 (4.6%) revisions, median time-to-revision postprimary surgery 1.8 years (range 0-8.8), with 1055 (0.6%) mid-late term revisions; in CPRD GOLD, 877 (5.1%) revisions, median time-to-revision 4.2 years (range 0.02-18.3), with 352 (2.0%) mid-late term revisions.Reduced risk of revision after 5 years was associated with older age (HR: 0.95; 95% CI 0.95 to 0.96), obesity (0.70; 0.56 to 0.88), living in deprived areas (0.71; 0.58 to 0.87), non-white ethnicity (0.58; 0.43 to 0.78), better preoperative pain and functional limitation (0.42; 0.33 to 0.53), better 6-month postoperative pain and function (0.33; 0.26 to 0.41) or moderate anxiety/depression (0.73; 0.63 to 0.83) at primary surgery.Increased risk was associated with male gender (1.32; 1.04 to 1.67); when anticonvulsants (gabapentin and pregabalin) (1.58; 1.01 to 2.47) or opioids (1.36; 1.08 to 1.71) were required prior to primary surgery.No implant factors were identified. CONCLUSION: The risk of mid-late term KR revision is very low. Increased risk of revision is associated with patient case-mix factors, and there is evidence of sociodemographic inequality

Association between outpatient follow-up and incidence of revision after knee and hip replacements: a population-based cohort study

Background: Follow-up visits 5 or 7 years after surgery were recommended for people having primary hip or knee replacement. The benefits of this practice to patients and the healthcare system, however, have not yet been specifically examined. The aim of this study was to investigate the association between long-term follow-up outpatient hospital visits and revision rates for patients who undergo primary knee or hip replacement surgery. Methods: Cohorts were identified for patients undergoing knee or hip replacement surgery using medical records from primary care practices within the UK Clinical Practice Research Datalink (CPRD) GOLD dataset linked to hospital records from the English Hospital Episodes Statistics (HES) data. Two groups of patients were compared in terms of revision and mortality rates: those with at least one long-term (between five and 10 years since primary surgery) follow-up visit at the orthopaedic department (‘Follow-up’ group), and those without (‘No follow-up’ group). Results: A total of 9856 (4349 in the Follow-up group) patients with knee replacement and 10,837 (4870 in the Follow-up group) with hip replacement were included in the analysis. For knee replacement, the incidence of revision was 3.6% for those followed-up and 0.6% for those not followed-up. An adjusted regression model confirmed the difference in the hazard ratio (HR) for revision was statistically significant (HR: 5.65 [95% CI 3.62 to 8.81]). Mortality at 4 years was lower for the Follow-up (17%) compared to the No follow-up group (21%), but this difference was not statistically significant (HR: 0.95 [0.84 to 1.07]). For hip replacement, the incidence of revision rates were 3.2 and 1.4% for the follow-up and not follow-up groups, respectively, the difference being statistically significant (HR: 2.34 [1.71 to 3.20]). Mortality was lower for the Follow-up (15%) compared to the No follow-up group (21%), but the difference was not statistically significant (HR: 0.91 [0.81 to 1.02]). Conclusion: Patients attending follow-up orthopaedic consultations show a higher risk of revision surgery compared to those who are not followed-up. A cause for this difference could not be identified in this study but a likely explanation is that surgeons play an effective role as ultimate arbitrators when identifying patients to be included in long-term follow-up lists

Risk factors associated with poor pain outcomes following primary knee replacement surgery: analysis of data from the Clinical Practice Research Datalink, Hospital Episode Statistics and Patient Reported Outcomes as part of the STAR research programme

OBJECTIVE: Identify risk factors for poor pain outcomes six months after primary knee replacement surgery. METHODS: Observational cohort study on patients receiving primary knee replacement from the UK Clinical Practice Research Datalink, Hospital Episode Statistics and Patient Reported Outcomes. A wide range of variables routinely collected in primary and secondary care were identified as potential predictors of worsening or only minor improvement in pain, based on the Oxford Knee Score pain subscale. Results are presented as relative risk ratios and adjusted risk differences (ARD) by fitting a generalized linear model with a binomial error structure and log link function. RESULTS: Information was available for 4,750 patients from 2009 to 2016, with a mean age of 69, of whom 56.1% were female. 10.4% of patients had poor pain outcomes. The strongest effects were seen for pre-operative factors: mild knee pain symptoms at the time of surgery (ARD 18.2% (95% Confidence Interval 13.6, 22.8), smoking 12.0% (95% CI:7.3, 16.6), living in the most deprived areas 5.6% (95% CI:2.3, 9.0) and obesity class II 6.3% (95% CI:3.0, 9.7). Important risk factors with more moderate effects included a history of previous knee arthroscopy surgery 4.6% (95% CI:2.5, 6.6), and use of opioids 3.4% (95% CI:1.4, 5.3) within three months after surgery. Those patients with worsening pain state change had more complications by 3 months (11.8% among those in a worse pain state vs. 2.7% with the same pain state). CONCLUSIONS: We quantified the relative importance of individual risk factors including mild pre-operative pain, smoking, deprivation, obesity and opioid use in terms of the absolute proportions of patients achieving poor pain outcomes. These findings will support development of interventions to reduce the numbers of patients who have poor pain outcomes

A reference case for economic evaluations in osteoarthritis: An expert consensus article from the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO)

Background: General recommendations for a reference case for economic studies in rheumatic diseases were published in 2002 in an initiative to improve the comparability of cost-effectiveness studies in the field. Since then, economic evaluations in osteoarthritis (OA) continue to show considerable heterogeneity in methodological approach. Objectives: To develop a reference case specific for economic studies in OA, including the standard optimal care, with which to judge new pharmacologic and non-pharmacologic interventions. Methods: Four subgroups of an ESCEO expert working group on economic assessments (13 experts representing diverse aspects of clinical research and/or economic evaluations) were charged with producing lists of recommendations that would potentially improve the comparability of economic analyses in OA: outcome measures, comparators, costs and methodology. These proposals were discussed and refined during a face-to-face meeting in 2013. They are presented here in the format of the recommendations of the recently published Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement, so that an initiative on economic analysis methodology might be consolidated with an initiative on reporting standards. Results: Overall, three distinct reference cases are proposed, one for each hand, knee and hip OA; with diagnostic variations in the first two, giving rise to different treatment options: interphalangeal or thumb-based disease for hand OA and the presence or absence of joint malalignment for knee OA. A set of management strategies is proposed, which should be further evaluated to help establish a consensus on the "standard optimal care" in each proposed reference case. The recommendations on outcome measures, cost itemisation and methodological approaches are also provided. Conclusions: The ESCEO group proposes a set of disease-specific recommendations on the conduct and reporting of economic evaluations in OA that could help the standardisation and comparability of studies that evaluate therapeutic strategies of OA in terms of costs and effectiveness

Safety of disinvestment in mid- to late-term follow-up post primary hip and knee replacement: The UK SAFE evidence synthesis and recommendations

Background: Joint replacement surgery has revolutionised the management of degenerative joint disease. Increasing demand for surgery and post-surgical reviews has overwhelmed orthopaedic services and, consequently, many centres have reduced or stopped follow-up. Such disinvestment is without an evidence base and raises questions regarding the consequences to patients.Objectives: To produce evidence- and consensus-based recommendations as to how, when and on whom follow-up should be conducted. Our research question was ‘Is it safe to disinvest in mid- to late-term follow-up of hip and knee replacement?’.MethodsThe study comprised three complementary evidence synthesis work packages to inform a final consensus process. Work package 1 was a systematic review of the clinical effectiveness and cost-effectiveness literature. Work package 2 used routine national data sets (i.e. the Clinical Practice Research Datalink–Hospital Episode Statistics, Hospital Episode Statistics–National Joint Registry–patient-reported outcome measures) to identify pre, peri and postoperative predictors of mid- to late-term revision, and prospective data from 560 patients to understand how patients present for revision surgery. Work package 3 used a Markov model to simulate the survival, health-related quality of life and NHS costs of patients following hip or knee replacement surgery. Finally, evidence from work packages 1–3 informed a face-to-face consensus panel, which involved 32 stakeholders.Results: Our overarching statements are as follows: (1) these recommendations apply to post primary hip and knee replacement follow-up; (2) the 10-year time point in these recommendations is based on a lack of robust evidence beyond 10 years; and (3) in these recommendations, the term ‘complex cases’ refers to individual patient and surgical factors that may increase the risk of replacement failure. Our recommendations are as follows: for Orthopaedic Data Evaluation Panel 10A* (ODEP-10A*) minimum implants, it is safe to disinvest in routine follow-up from 1 to 10 years post non-complex hip and knee replacement provided that there is rapid access to orthopaedic review; (2) for ODEP-10A* minimum implants in complex cases or non-ODEP-10A* minimum implants, periodic follow-up post hip and knee replacement may be required from 1 to 10 years; (3) at 10 years post hip and knee replacement, clinical and radiographic evaluation is recommended; and (4) after 10 years post hip and knee replacement, frequency of further follow-up should be based on the 10-year assessment (note that ongoing rapid access to orthopaedic review is still required) [Stone M, Smith L, Kingsbury S, Czoski-Murray C, Judge A, Pinedo-Villanueva R, et al. Evidence-based follow-up recommendations following primary hip and knee arthroplasty (UK SAFE). Orthop Proc 2020;102–B:13. https://doi.org/10.1302/1358-992X.2020.5.013].Limitations: The current absence of data beyond 10 years restricted the evidence base.Conclusions: For ODEP-10A* prostheses, the UK SAFE programme demonstrated that it is safe to disinvest in routine follow-up in the 1- to 10-year period after non-complex hip and knee replacement. At 10 years, clinical and radiographic review is recommended. Complex cases, implants not meeting the 10A* criteria and follow-up after revision surgery are not covered by this recommendation.Future work: The evidence base for follow-up after 10 years requires further evaluation. Further work should establish the most clinically effective and cost-effective model of delivering a rapid access service and evaluate alternative models for follow-up services, such as virtual clinics. Finally, the needs and outcomes of patients who are symptomatic but do not have appropriate follow-up should be investigated

Mid- to late-term follow-up of primary hip and knee arthroplasty: the UK SAFE evidence-based recommendations

Aims: To review the evidence and reach consensus on recommendations for follow-up after total hip and knee arthroplasty. Methods: A programme of work was conducted, including: a systematic review of the clinical and cost-effectiveness literature; analysis of routine national datasets to identify pre-, peri-, and postoperative predictors of mid-to-late term revision; prospective data analyses from 560 patients to understand how patients present for revision surgery; qualitative interviews with NHS managers and orthopaedic surgeons; and health economic modelling. Finally, a consensus meeting considered all the work and agreed the final recommendations and research areas. Results: The UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE) recommendations apply to post-primary hip and knee arthroplasty follow-up. The ten-year time point is based on a lack of robust evidence beyond ten years. The term 'complex cases' refers to individual patient and surgical factors that may increase the risk for arthroplasty failure. For Orthopaedic Data Evaluation Panel (ODEP) 10A* minimum implants, it is safe to disinvest in routine follow-up from one to years post-non-complex hip and knee arthroplasty provided there is rapid access to orthopaedic review. For ODEP 10A* minimum implants in complex cases, or non-ODEP 10A* minimum implants, periodic follow-up post-hip and knee arthroplasty may be required from one to ten years. At ten years post-hip and knee arthroplasty, clinical and radiological evaluation is recommended. After ten years post-hip and knee arthroplasty, frequency of further follow-up should be based on the ten-year assessment; ongoing rapid access to orthopaedic review is still required. Conclusion: Complex cases, implants not meeting the ODEP 10A* criteria, and follow-up after revision surgery are not covered by this recommendation. Cite this article: Bone Jt Open 2023;4(2):72–78

Mid- to late-term follow-up of primary hip and knee arthroplasty: the UK SAFE evidence-based recommendations

AimsTo review the evidence and reach consensus on recommendations for follow-up after total hip and knee arthroplasty.MethodsA programme of work was conducted, including: a systematic review of the clinical and cost-effectiveness literature; analysis of routine national datasets to identify pre-, peri-, and postoperative predictors of mid-to-late term revision; prospective data analyses from 560 patients to understand how patients present for revision surgery; qualitative interviews with NHS managers and orthopaedic surgeons; and health economic modelling. Finally, a consensus meeting considered all the work and agreed the final recommendations and research areas.ResultsThe UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE) recommendations apply to post-primary hip and knee arthroplasty follow-up. The ten-year time point is based on a lack of robust evidence beyond ten years. The term 'complex cases' refers to individual patient and surgical factors that may increase the risk for arthroplasty failure. For Orthopaedic Data Evaluation Panel (ODEP) 10A* minimum implants, it is safe to disinvest in routine follow-up from one to years post-non-complex hip and knee arthroplasty provided there is rapid access to orthopaedic review. For ODEP 10A* minimum implants in complex cases, or non-ODEP 10A* minimum implants, periodic follow-up post-hip and knee arthroplasty may be required from one to ten years. At ten years post-hip and knee arthroplasty, clinical and radiological evaluation is recommended. After ten years post-hip and knee arthroplasty, frequency of further follow-up should be based on the ten-year assessment; ongoing rapid access to orthopaedic review is still required.ConclusionComplex cases, implants not meeting the ODEP 10A* criteria, and follow-up after revision surgery are not covered by this recommendation.Cite this article: Bone Jt Open 2023;4(2):72–78

UK poSt Arthroplasty Follow-up rEcommendations (UK SAFE): what does analysis of linked, routinely collected national datasets tell us about mid-late term revision risk after knee replacement?

Objective: to identify patients at risk of mid-late term revision of knee replacement (KR) to inform targeted follow-up.Design: analysis of linked national datasets from primary and secondary care (Clinical Practice Research Datalink (CPRD GOLD), National Joint Registry (NJR), English Hospital Episode Statistics (HES) and Patient Reported Outcome Measures (PROMs)).Participants: primary elective KRs aged ≥18 years.Event of interest: revision surgery ≥5 years (mid-late term) postprimary KR.Statistical methods: cox regression modelling to ascertain risk factors of mid-late term revision. HRs and 95% CIs assessed association of sociodemographic factors, comorbidities, medication, surgical variables and PROMs with mid-late term revision.Results: NJR-HES-PROMs data were available from 2008 to 2011 on 188 509 KR. CPRD GOLD-HES data covered 1995-2011 on 17 378 KR. Patients had minimum 5 years postprimary surgery to end 2016. Age and gender distribution were similar across datasets; mean age 70 years, 57% female. In NJR, there were 8607 (4.6%) revisions, median time-to-revision postprimary surgery 1.8 years (range 0-8.8), with 1055 (0.6%) mid-late term revisions; in CPRD GOLD, 877 (5.1%) revisions, median time-to-revision 4.2 years (range 0.02-18.3), with 352 (2.0%) mid-late term revisions.Reduced risk of revision after 5 years was associated with older age (HR: 0.95; 95% CI 0.95 to 0.96), obesity (0.70; 0.56 to 0.88), living in deprived areas (0.71; 0.58 to 0.87), non-white ethnicity (0.58; 0.43 to 0.78), better preoperative pain and functional limitation (0.42; 0.33 to 0.53), better 6-month postoperative pain and function (0.33; 0.26 to 0.41) or moderate anxiety/depression (0.73; 0.63 to 0.83) at primary surgery.Increased risk was associated with male gender (1.32; 1.04 to 1.67); when anticonvulsants (gabapentin and pregabalin) (1.58; 1.01 to 2.47) or opioids (1.36; 1.08 to 1.71) were required prior to primary surgery.No implant factors were identified.Conclusions: the risk of mid-late term KR revision is very low. Increased risk of revision is associated with patient case-mix factors, and there is evidence of sociodemographic inequality.</p