Patient information leaflets for placebo-controlled surgical trials: a review of current practice and recommendations for developers

INTRODUCTION

Informed consent for participation in an RCT is an important ethical and legal requirement. In placebo surgical trials, further issues are raised, and to date, this has not been explored. Patient information leaflets (PILs) are a core component of the informed consent process. This study aimed to investigate the key content of PILs for recently completed placebo-controlled trials of invasive procedures, including surgery, to highlight areas of good practice, identify gaps in information provision for trials of this type and provide recommendations for practice.

METHODS

PILs were sought from trials included in a recent systematic review of placebo-controlled trials of invasive procedures, including surgery. Trial characteristics and data on surgical and placebo interventions under evaluation were extracted. Directed content analysis was applied, informed by published regulatory and good practice guidance on PIL content and existing research on placebo-controlled surgical trials. Results were analysed using descriptive statistics and presented as a narrative summary.

RESULTS

Of the 62 eligible RCTs, authors of 59 trials were contactable and 14 PILs were received for analysis. At least 50% of all PILs included content on general trial design. Explanations of how the placebo differs or is similar to the surgical intervention (i.e. fidelity) were reported in 6 (43%) of the included PILs. Over half (57%) of the PILs included information on the potential therapeutic benefits of the surgical intervention. One (7%) included information on potential indirect therapeutic benefits from invasive components of the placebo. Five (36%) presented the known risks of the placebo intervention, whilst 8 (57%) presented information on the known risks of the surgical intervention. A range of terms was used across the PILs to describe the placebo component, including 'control', 'mock' and 'sham'.

CONCLUSION

Developers of PILs for placebo-controlled surgical trials should carefully consider the use of language (e.g. sham, mock), be explicit about how the placebo differs (or is similar) to the surgical intervention and provide balanced presentations of potential benefits and risks of the surgical intervention separately from the placebo. Further research is required to determine optimal approaches to design and deliver this information for these trials.

Implementing a shared decision-making intervention to support treatment decisions for patients following an anterior cruciate ligament rupture - a protocol for the POP-ACLR feasibility study

BACKGROUND

Treatment for anterior cruciate ligament (ACL) rupture may follow a surgical or nonsurgical pathway. At present, there is uncertainty around treatment choice. Two shared decision-making tools have been codesigned to support patients to make a decision about treatment following an ACL rupture. The shared decision-making tools include a patient information leaflet and an option grid. We report the protocol for a mixed-methods feasibility study, with nested qualitative interviews, to understand feasibility, acceptability, indicators of effectiveness and implementation factors of these shared decision-making tools (combined to form one shared decision-making intervention).

METHODS

A single-centre non-randomised feasibility study will be conducted with 20 patients. Patients diagnosed with an ACL rupture following magnetic resonance imaging will be identified from an orthopaedic clinic. The shared decision-making intervention will be delivered during a clinical consultation with a physiotherapist. The primary feasibility outcomes include the following: recruitment rate, fidelity, acceptability and follow-up questionnaire completion. The secondary outcome is the satisfaction with decision scale. The nested qualitative interview will explore experience of using the shared decision-making intervention to understand acceptability, implementation factors and areas for further refinement.

DISCUSSION

This study will determine the feasibility of using a newly developed shared decision-making intervention designed to support patients to make a decision about treatment of their ACL rupture. The acceptability and indicators of effectiveness will also be explored. In the long term, the shared decision-making intervention may improve service and patient outcomes and ensure cost-effectiveness for the NHS; ensuring those most likely to benefit from surgical treatment proceed along this pathway.

TRIAL REGISTRATION

Pending registration on ISRCTN.

Cost-effectiveness analysis of a pragmatic randomized trial evaluating surgical reconstruction versus rehabilitation in patients with long-standing anterior cruciate ligament injury

Aims

The aim of this study was to estimate the incremental use of resources, costs, and quality of life outcomes associated with surgical reconstruction compared to rehabilitation for long-standing anterior cruciate ligament (ACL) injury in the NHS, and to estimate its cost-effectiveness.

Methods

A total of 316 patients were recruited and randomly assigned to either surgical reconstruction or rehabilitation (physiotherapy but with subsequent reconstruction permitted if instability persisted after treatment). Healthcare resource use and health-related quality of life data (EuroQol five-dimension five-level health questionnaire) were collected in the trial at six, 12, and 18 months using self-reported questionnaires and medical records. Using intention-to-treat analysis, differences in costs, and quality-adjusted life years (QALYs) between treatment arms were estimated adjusting for baseline differences and following multiple imputation of missing data. The incremental cost-effectiveness ratio (ICER) was estimated as the difference in costs divided by the difference in QALYs between reconstruction and rehabilitation.

Results

At 18 months, patients in the surgical reconstruction arm reported higher QALYs (0.052 (95% confidence interval (CI) -0.012 to 0.117); p = 0.177) and higher NHS costs (£1,017 (95% CI 557 to 1,476); p < 0.001) compared to rehabilitation. This resulted in an ICER of £19,346 per QALY with the probability of surgical reconstruction being cost-effective of 51% and 72% at a willingness-to-pay threshold of £20,000 and £30,000 per QALY, respectively.

Conclusion

Surgical reconstruction as a management strategy for patients with long-standing ACL injury is more effective, but more expensive, at 18 months compared to rehabilitation management. In the UK setting, surgical reconstruction is cost-effective.

The IDEAL framework for surgical robotics: development, comparative evaluation and long-term monitoring

The next generation of surgical robotics is poised to disrupt healthcare systems worldwide, requiring new frameworks for evaluation. However, evaluation during a surgical robot's development is challenging due to their complex evolving nature, potential for wider system disruption and integration with complementary technologies like artificial intelligence. Comparative clinical studies require attention to intervention context, learning curves and standardized outcomes. Long-term monitoring needs to transition toward collaborative, transparent and inclusive consortiums for real-world data collection. Here, the Idea, Development, Exploration, Assessment and Long-term monitoring (IDEAL) Robotics Colloquium proposes recommendations for evaluation during development, comparative study and clinical monitoring of surgical robots-providing practical recommendations for developers, clinicians, patients and healthcare systems. Multiple perspectives are considered, including economics, surgical training, human factors, ethics, patient perspectives and sustainability. Further work is needed on standardized metrics, health economic assessment models and global applicability of recommendations.

How do pilot and feasibility studies inform randomised placebo-controlled trials in surgery? A systematic review

INTRODUCTION

Randomised controlled trials (RCTs) with a placebo comparator are considered the gold standard study design when evaluating healthcare interventions. These are challenging to design and deliver in surgery. Guidance recommends pilot and feasibility work to optimise main trial design and conduct; however, the extent to which this occurs in surgery is unknown.

METHOD

A systematic review identified randomised placebo-controlled surgical trials. Articles published from database inception to 31 December 2020 were retrieved from Ovid-MEDLINE, Ovid-EMBASE and CENTRAL electronic databases, hand-searching and expert knowledge. Pilot/feasibility work conducted prior to the RCTs was then identified from examining citations and reference lists. Where studies explicitly stated their intent to inform the design and/or conduct of the future main placebo-controlled surgical trial, they were included. Publication type, clinical area, treatment intervention, number of centres, sample size, comparators, aims and text about the invasive placebo intervention were extracted.

RESULTS

From 131 placebo surgical RCTs included in the systematic review, 47 potentially eligible pilot/feasibility studies were identified. Of these, four were included as true pilot/feasibility work. Three were original articles, one a conference abstract; three were conducted in orthopaedic surgery and one in oral and maxillofacial surgery. All four included pilot RCTs, with an invasive surgical placebo intervention, randomising 9-49 participants in 1 or 2 centres. They explored the acceptability of recruitment and the invasive placebo intervention to patients and trial personnel, and whether blinding was possible. One study examined the characteristics of the proposed invasive placebo intervention using in-depth interviews.

CONCLUSION

Published studies reporting feasibility/pilot work undertaken to inform main placebo surgical trials are scarce. In view of the difficulties of undertaking placebo surgical trials, it is recommended that pilot/feasibility studies are conducted, and more are reported to share key findings and optimise the design of main RCTs.

PROSPERO REGISTRATION NUMBER

CRD42021287371.

Patient-Relevant Outcomes Following First Revision Total Knee Arthroplasty, by Diagnosis: An Analysis of Implant Survivorship, Mortality, Serious Medical Complications, and Patient-Reported Outcome Measures Utilizing the National Joint Registry Data Set

BACKGROUND

The purpose of this study was to investigate patient-relevant outcomes following first revision total knee arthroplasties (rTKAs) performed for different indications.

METHODS

This population-based cohort study utilized data from the United Kingdom National Joint Registry, Hospital Episode Statistics Admitted Patient Care, National Health Service Patient-Reported Outcome Measures, and the Civil Registrations of Death. Patients undergoing a first rTKA between January 1, 2009, and June 30, 2019, were included in our data set. Patient-relevant outcomes included implant survivorship (up to 11 years postoperatively), mortality and serious medical complications (up to 90 days postoperatively), and patient-reported outcome measures (at 6 months postoperatively).

RESULTS

A total of 24,540 first rTKAs were analyzed. The patient population was 54% female and 62% White, with a mean age at the first rTKA of 69 years. At 2 years postoperatively, the cumulative incidence of re-revision surgery ranged from 2.7% (95% confidence interval [CI], 1.9% to 3.4%) following rTKA for progressive arthritis to 16.3% (95% CI, 15.2% to 17.4%) following rTKA for infection. The mortality rate at 90 days was highest following rTKA for fracture (3.6% [95% CI, 2.5% to 5.1%]) and for infection (1.8% [95% CI, 1.5% to 2.2%]) but was <0.5% for other indications. The rate of serious medical complications requiring hospital admission within 90 days was highest for patients treated for fracture (21.8% [95% CI, 17.9% to 26.3%]) or infection (12.5% [95% CI, 11.2% to 13.9%]) and was lowest for those treated for progressive arthritis (4.3% [95% CI, 3.3% to 5.5%]). Patients who underwent rTKA for stiffness or unexplained pain had some of the poorest postoperative joint function (mean Oxford Knee Score, 24 and 25 points, respectively) and had the lowest proportion of responders (48% and 55%, respectively).

CONCLUSIONS

This study found large differences in patient-relevant outcomes among different indications for first rTKA. The rate of complications was highest following rTKA for fracture or infection. Although rTKA resulted in large improvements in joint function for most patients, those who underwent surgery for stiffness and unexplained pain had worse outcomes.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Epidemiology of revision hip replacement surgery in the UK over the past 15 years-an analysis from the National Joint Registry

OBJECTIVES

To investigate trends in the incidence rate and main indication for revision hip replacement (rHR) over the past 15 years in the UK.

DESIGN

Repeated national cross-sectional study from 2006 to 2020.

SETTING/PARTICIPANTS

rHR procedures were identified from the National Joint Registry for England, Wales, Northern Ireland, the Isle of Man and the States of Guernsey. Population statistics were obtained from the Office for National Statistics.

MAIN OUTCOME MEASURES

Crude incidence rates of rHR.

RESULTS

The incidence rate of rHR doubled from 11 per 100 000 adults in 2006 (95% CI 10.7 to 11.3) to a peak of 22 per 100 000 adults (95% CI 22 to 23) in 2012, before falling to 17 per 100 000 adults in 2019 (95% CI 16 to 17) (24.5% decrease from peak). The incidence rate of rHR reduced by 39% in 2020 compared with 2019 (during the COVID-19 pandemic). The most frequent indications for rHR between 2006 and 2019 were loosening/lysis (27.8%), unexplained pain (15.1%) and dislocation/instability (14.7%). There were incremental increases in the annual number and incidence rates of rHR for fracture, infection, dislocation/instability and a decrease in rHR for aseptic loosening/lysis.

CONCLUSIONS

The incidence rate of rHR doubled from 2006 to 2012, likely due to high early failure rates of metal-on-metal hip replacements. The incidence of rHR then decreased by approximately 25% from 2012 to 2019, followed by a large decrease during the COVID-19 pandemic. The decrease in the number of rHR performed for aseptic loosening/lysis may reflect improved wear and implant longevity. Increased healthcare resource will be required to care for the increasing numbers of patients undergoing rHR for fracture and infection.

Overcoming floor and ceiling effects in knee arthroplasty outcome measurement

Aims

To map the Oxford Knee Score (OKS) and High Activity Arthroplasty Score (HAAS) items to a common scale, and to investigate the psychometric properties of this new scale for the measurement of knee health.

Methods

Patient-reported outcome measure (PROM) data measuring knee health were obtained from the NHS PROMs dataset and Total or Partial Knee Arthroplasty Trial (TOPKAT). Assumptions for common scale modelling were tested. A graded response model (fitted to OKS item responses in the NHS PROMs dataset) was used as an anchor to calibrate paired HAAS items from the TOPKAT dataset. Information curves for the combined OKS-HAAS model were plotted. Bland-Altman analysis was used to compare common scale scores derived from OKS and HAAS items. A conversion table was developed to map between HAAS, OKS, and the common scale.

Results

We included 3,329 response sets from 528 patients undergoing knee arthroplasty. These generally met the assumptions of unidimensionality, monotonicity, local independence, and measurement invariance. The HAAS items provided more information than OKS items at high levels of knee health. Combining both instruments resulted in higher test-level information than either instrument alone. The mean error between common scale scores derived from the OKS and HAAS was 0.29 logits.

Conclusion

The common scale allowed more precise measurement of knee health than use of either the OKS or HAAS individually. These techniques for mapping PROM instruments may be useful for the standardization of outcome reporting, and pooling results across studies that use either PROM in individual-patient meta-analysis.

Remote Symptom Monitoring With Ecological Momentary Computerized Adaptive Testing: Pilot Cohort Study of a Platform for Frequent, Low-Burden, and Personalized Patient-Reported Outcome Measures

BACKGROUND

Remote patient-reported outcome measure (PROM) data capture can provide useful insights into research and clinical practice and deeper insights can be gained by administering assessments more frequently, for example, in ecological momentary assessment. However, frequent data collection can be limited by the burden of multiple, lengthy questionnaires. This burden can be reduced with computerized adaptive testing (CAT) algorithms that select only the most relevant items from a PROM for an individual respondent. In this paper, we propose "ecological momentary computerized adaptive testing" (EMCAT): the use of CAT algorithms to reduce PROM response burden and facilitate high-frequency data capture via a smartphone app. We develop and pilot a smartphone app for performing EMCAT using a popular hand surgery PROM.

OBJECTIVE

The aim of this study is to determine the feasibility of EMCAT as a system for remote PROM administration.

METHODS

We built the EMCAT web app using Concerto, an open-source CAT platform maintained by the Psychometrics Centre, University of Cambridge, and hosted it on an Amazon Web Service cloud server. The platform is compatible with any questionnaire that has been parameterized with item response theory or Rasch measurement theory. For this study, the PROM we chose was the patient evaluation measure, which is commonly used in hand surgery. CAT algorithms were built using item response theory models derived from UK Hand Registry data. In the pilot study, we enrolled 40 patients with hand trauma or thumb-base arthritis, across 2 sites, between July 13, 2022, and September 14, 2022. We monitored their symptoms with the patient evaluation measure, via EMCAT, over a 12-week period. Patients were assessed thrice weekly, once daily, or thrice daily. We additionally administered full-length PROM assessments at 0, 6, and 12 weeks, and the User Engagement Scale at 12 weeks.

RESULTS

The use of EMCAT significantly reduced the length of the PROM (median 2 vs 11 items) and the time taken to complete it (median 8.8 seconds vs 1 minute 14 seconds). Very similar scores were obtained when EMCAT was administered concurrently with the full-length PROM, with a mean error of <0.01 on a logit (z score) scale. The median response rate in the daily assessment group was 93%. The median perceived usability score of the User Engagement Scale was 4.0 (maximum possible score 5.0).

CONCLUSIONS

EMCAT reduces the burden of PROM assessments, enabling acceptable high-frequency, remote PROM data capture. This has potential applications in both research and clinical practice. In research, EMCAT could be used to study temporal variations in symptom severity, for example, recovery trajectories after surgery. In clinical practice, EMCAT could be used to monitor patients remotely, prompting early intervention if a patient's symptom trajectory causes clinical concern.

TRIAL REGISTRATION

ISRCTN 19841416; https://www.isrctn.com/ISRCTN19841416.

Cost-effectiveness of replacing versus discarding the nail in children with nail bed injury

Every year in the UK, around 10 000 children need to have operations to mend injuries to the bed of their fingernails. Currently, most children have their fingernail placed back on the injured nail bed after the operation. The NINJA trial found that children were slightly less likely to have an infection if the nail was thrown away rather than being put back, but the difference between groups was small and could have be due to chance. This study looked at whether replacing the nail is cost-effective compared with throwing it away. Using data from the NINJA trial, we compared costs, healthcare use, and quality of life and assessed the cost-effectiveness of replacing the nail. It was found that throwing the nail away after surgery would save the National Health Service (NHS) £75 (€85) per operation compared with placing the nail back on the nail bed. Changing clinical practice could save the NHS in England £720 000 (€819 000) per year.

Patient-relevant outcomes following elective, aseptic revision knee arthroplasty: a systematic review

BACKGROUND

The aim of this systematic review was to summarise the evidence for the clinical effectiveness of revision knee arthroplasty (rKA) compared to non-operative treatment for the management of patients with elective, aseptic causes for a failed knee arthroplasty.

METHODS

MEDLINE, Embase, AMED and PsychINFO were searched from inception to 1st December 2020 for studies on patients considering elective, aseptic rKA. Patient-relevant outcomes (PROs) were defined as implant survivorship, joint function, quality of life (QoL), complications and hospital admission impact.

RESULTS

No studies compared elective, aseptic rKA to non-operative management. Forty uncontrolled studies reported on PROs following elective, aseptic rKA (434434 rKA). Pooled estimates for implant survivorship were: 95.5% (95% CI 93.2-97.7%) at 1 year [seven studies (5524 rKA)], 90.8% (95% CI 87.6-94.0%) at 5 years [13 studies (5754 rKA)], 87.4% (95% CI 81.7-93.1%) at 10 years [nine studies (2188 rKA)], and 83.2% (95% CI 76.7-89.7%) at 15 years [two studies (452 rKA)]. Twelve studies (2382 rKA) reported joint function and/or QoL: all found large improvements from baseline to follow-up. Mortality rates were low (0.16% to 2% within 1 year) [four studies (353064 rKA)]. Post-operative complications were common (9.1 to 37.2% at 90 days).

CONCLUSION

Higher-quality evidence is needed to support patients with decision-making in elective, aseptic rKA. This should include studies comparing operative and non-operative management. Implant survivorship following elective, aseptic rKA was ~ 96% at 1 year, ~ 91% at 5 years and ~ 87% at 10 years. Early complications were common after elective, aseptic rKA and the rates summarised here can be shared with patients during informed consent.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020196922.

Further considerations for placebo controls in surgical trials

The use of invasive placebo controls in surgical trials can be challenging. The ASPIRE guidance, published in the Lancet in 2020, provided advice for the design and conduct of surgical trials with an invasive placebo control. Based on a more recent international expert workshop in June 2022, we now provide further insights into this topic. These include the purpose and design of invasive placebo controls, patient information provision and how findings from these trials may be used to inform decision-making.

Item response theory assumptions were adequately met by the Oxford hip and knee scores

OBJECTIVES

To develop item response theory (IRT) models for the Oxford hip and knee scores which convert patient responses into continuous scores with quantifiable precision and provide these as web applications for efficient score conversion.

STUDY DESIGN AND SETTING

Data from the National Health Service patient-reported outcome measures program were used to test the assumptions of IRT (unidimensionality, monotonicity, local independence, and measurement invariance) before fitting models to preoperative response patterns obtained from patients undergoing primary elective hip or knee arthroplasty. The hip and knee datasets contained 321,147 and 355,249 patients, respectively.

RESULTS

Scree plots, Kaiser criterion analyses, and confirmatory factor analyses confirmed unidimensionality and Mokken analysis confirmed monotonicity of both scales. In each scale, all item pairs shared a residual correlation of ≤ 0.20. At the test level, both scales showed measurement invariance by age and gender. Both scales provide precise measurement in preoperative settings but demonstrate poorer precision and ceiling effects in postoperative settings.

CONCLUSION

We provide IRT parameters and web applications that can convert Oxford Hip Score or Oxford Knee Score response sets into continuous measurements and quantify individual measurement error. These can be used in sensitivity analyses or to administer truncated and individualized computerized adaptive tests.

Item response theory may account for unequal item weighting and individual-level measurement error in trials that use PROMs: a psychometric sensitivity analysis of the TOPKAT trial

OBJECTIVES

To apply item response theory as a framework for studying measurement error in superiority trials which use patient-reported outcome measures (PROMs).

METHODS

We reanalyzed data from the The Total or Partial Knee Arthroplasty Trial, which compared the Oxford Knee Score (OKS) responses of patients undergoing partial or total knee replacement, using traditional sum-scoring, after accounting for OKS item characteristics with expected a posteriori (EAP) scoring, and after accounting for individual-level measurement error with plausible value imputation (PVI). We compared the marginalized mean scores of each group at baseline, 2 months, and yearly for 5 years. We used registry data to estimate the minimal important difference (MID) of OKS scores with sum-scoring and EAP scoring.

RESULTS

With sum-scoring, we found statistically significant differences in mean OKS score at 2 months (P = 0.030) and 1 year (P = 0.030). EAP scores produced slightly different results, with statistically significant differences at 1 year (P = 0.041) and 3 years (P = 0.043). With PVI, there were no statistically significant differences.

CONCLUSION

Psychometric sensitivity analyses can be readily performed for superiority trials using PROMs and may aid the interpretation of results.

Effectiveness of nail bed repair in children with or without replacing the fingernail: NINJA multicentre randomized clinical trial

BACKGROUND

Surgery for nail bed injuries in children is common. One of the key surgical decisions is whether to replace the nail plate following nail bed repair. The aim of this RCT was to assess the clinical effectiveness and cost-effectiveness of nail bed repair with fingernail replacement/substitution compared with repair without fingernail replacement.

METHODS

A two-arm 1 : 1 parallel-group open multicentre superiority RCT was performed across 20 secondary-care hospitals in the UK. The co-primary outcomes were surgical-site infection at around 7 days after surgery and cosmetic appearance summary score at a minimum of 4 months.

RESULTS

Some 451 children presenting with a suspected nail bed injury were recruited between July 2018 and July 2019; 224 were allocated to the nail-discarded arm, and 227 to the nail-replaced arm. There was no difference in the number of surgical-site infections at around 7 days between the two interventions or in cosmetic appearance. The mean total healthcare cost over the 4 months after surgery was €84 (95 per cent c.i. 34 to 140) lower for the nail-discarded arm than the nail-replaced arm (P < 0.001).

CONCLUSION

After nail bed repair, discarding the fingernail was associated with similar rates of infection and cosmesis ratings as replacement of the finger nail, but was cost saving. Registration number: ISRCTN44551796 (http://www.controlled-trials.com).

Rehabilitation versus surgical reconstruction for non-acute anterior cruciate ligament injury (ACL SNNAP): a pragmatic randomised controlled trial

BACKGROUND

Anterior cruciate ligament (ACL) rupture is a common debilitating injury that can cause instability of the knee. We aimed to investigate the best management strategy between reconstructive surgery and non-surgical treatment for patients with a non-acute ACL injury and persistent symptoms of instability.

METHODS

We did a pragmatic, multicentre, superiority, randomised controlled trial in 29 secondary care National Health Service orthopaedic units in the UK. Patients with symptomatic knee problems (instability) consistent with an ACL injury were eligible. We excluded patients with meniscal pathology with characteristics that indicate immediate surgery. Patients were randomly assigned (1:1) by computer to either surgery (reconstruction) or rehabilitation (physiotherapy but with subsequent reconstruction permitted if instability persisted after treatment), stratified by site and baseline Knee Injury and Osteoarthritis Outcome Score-4 domain version (KOOS4). This management design represented normal practice. The primary outcome was KOOS4 at 18 months after randomisation. The principal analyses were intention-to-treat based, with KOOS4 results analysed using linear regression. This trial is registered with ISRCTN, ISRCTN10110685, and ClinicalTrials.gov, NCT02980367.

FINDINGS

Between Feb 1, 2017, and April 12, 2020, we recruited 316 patients. 156 (49%) participants were randomly assigned to the surgical reconstruction group and 160 (51%) to the rehabilitation group. Mean KOOS4 at 18 months was 73·0 (SD 18·3) in the surgical group and 64·6 (21·6) in the rehabilitation group. The adjusted mean difference was 7·9 (95% CI 2·5-13·2; p=0·0053) in favour of surgical management. 65 (41%) of 160 patients allocated to rehabilitation underwent subsequent surgery according to protocol within 18 months. 43 (28%) of 156 patients allocated to surgery did not receive their allocated treatment. We found no differences between groups in the proportion of intervention-related complications.

INTERPRETATION

Surgical reconstruction as a management strategy for patients with non-acute ACL injury with persistent symptoms of instability was clinically superior and more cost-effective in comparison with rehabilitation management.

FUNDING

The UK National Institute for Health Research Health Technology Assessment Programme.

Serious adverse event rates and reoperation after arthroscopic shoulder surgery: population based cohort study

OBJECTIVE

To provide clinicians and patients with accurate risk estimates of serious adverse events after common elective shoulder arthroscopic procedures, including reoperation within one year.

DESIGN

Population based cohort study.

SETTING

Hospital Episode Statistics for NHS England, including civil registration mortality data from the Office for National Statistics.

PARTICIPANTS

288 250 arthroscopic shoulder procedures performed in 261 248 patients aged ≥16 years between 1 April 2009 and 31 March 2017. Elective procedures were grouped into subacromial decompression, rotator cuff repair, acromioclavicular joint excision, glenohumeral stabilisation, and frozen shoulder release.

MAIN OUTCOME MEASURES

The primary outcomes were rates of serious adverse events (mortality, pulmonary embolism, pneumonia, myocardial infarction, acute kidney injury, stroke, and urinary tract infection) requiring inpatient care within 90 days post-surgery. Secondary outcomes were specific adverse event rates at 90 days, and reoperations (including for deep infection) within one year.

RESULTS

The overall rate of complications within 90 days after arthroscopic shoulder surgery (including reoperation) was low at 1.2% (95% confidence interval 1.2% to 1.3%), with one in 81 patients at risk, and varied according to type of procedure, from 0.6% (0.5% to 0.8%) for glenohumeral stabilisation to 1.7% (1.5% to 1.8%) for frozen shoulder release. After adjustment for age, comorbidities, and sex, no effect of procedure type was observed. Pneumonia was the most common adverse event (0.3%, 0.3% to 0.4%), with one in 303 patients at risk. Pulmonary embolic events were rare, at 0.1% (0.1% to 0.1%), with one in 1428 patients at risk. At one year, the overall rate for reoperation was 3.8% (3.8% to 3.9%), with one in 26 patients at risk, ranging from 2.7% (2.5% to 3.0%) for glenohumeral stabilisation to 5.7% (5.4% to 6.1%) for frozen shoulder release. The overall rate of further surgery for deep infection was low, at 0.1% (0.1% to 0.1%), with one in 1111 patients at risk, but was higher after rotator cuff repair (0.2%, 0.2% to 0.2%), with one in 526 patients at risk. Over the study period the number of arthroscopic shoulder procedures increased, except for subacromial decompression, which decreased.

CONCLUSIONS

The findings of this study suggest that risks of serious adverse events associated with common shoulder arthroscopy procedures are low. Nevertheless, serious complications do occur, and include the risk of reoperation in one in 26 patients within one year.

STUDY REGISTRATION

Clinical.

TRIALS

gov NCT03573765.

Early patient-reported outcomes from primary hip and knee arthroplasty have improved over the past seven years : an analysis of the NHS PROMs dataset

AIMS

Routinely collected patient-reported outcome measures (PROMs) have been useful to quantify and quality-assess provision of total hip arthroplasty (THA) and total knee arthroplasty (TKA) in the UK for the past decade. This study aimed to explore whether the outcome following primary THA and TKA had improved over the past seven years.

METHODS

Secondary data analysis of 277,430 primary THAs and 308,007 primary TKAs from the NHS PROMs programme was undertaken. Outcome measures were: postoperative Oxford Hip/Knee Score (OHS/OKS); proportion of patients achieving a clinically important improvement in joint function (responders); quality of life; patient satisfaction; perceived success; and complication rates. Outcome measures were compared based on year of surgery using multiple linear and logistic regression models.

RESULTS

For primary THA, multiple linear regression modelling found that more recent year of surgery was associated with higher postoperative OHS (unstandardized coefficient (B) 0.15 points (95% confidence interval (CI) 0.14 to 0.17); p < 0.001) and higher EuroQol five-dimension index (EQ-5D) utility (B 0.002 (95% CI 0.001 to 0.002); p < 0.001). The odds of being a responder (odds ratio (OR) 1.02 (95% CI 1.02 to 1.03); p < 0.001) and patient satisfaction (OR 1.02 (95% CI 1.01 to 1.03); p < 0.001) increased with year of surgery, while the odds of any complication reduced (OR 0.97 (95% CI 0.97 to 0.98); p < 0.001). No trend was found for perceived success (p = 0.555). For primary TKA, multiple linear regression modelling found that more recent year of surgery was associated with higher postoperative OKS (B 0.21 points (95% CI 0.19 to 0.22); p < 0.001) and higher EQ-5D utility (B 0.002 (95% CI 0.002 to 0.003); p < 0.001). The odds of being a responder (OR 1.04 (95% CI 1.03 to 1.04); p < 0.001), perceived success (OR 1.02 (95% CI 1.01 to 1.02); p < 0.001), and patient satisfaction (OR 1.02 (95% CI 1.01 to 1.02); p < 0.001) all increased with year of surgery, while the odds of any complication reduced (OR 0.97 (95% CI 0.97 to 0.97); p < 0.001).

CONCLUSION

Nearly all patient-reported outcomes following primary THA/TKA improved by a small amount over the past seven years. Due to the high proportion of patients achieving good outcomes, PROMs following THA and TKA may need to focus on better discrimination of patients achieving high scores to be able to continue to measure improvement in outcomes. Cite this article: Bone Joint J 2022;104-B(6):687-695.

ACL Surgery Necessity in Non-Acute Patients (ACL SNNAP): a statistical analysis plan for a randomised controlled trial

Background

Rupture of the anterior cruciate ligament (ACL) is a common injury, primarily affecting young, active individuals. Despite surgical intervention being the more common treatment for patients suffering ACL ruptures, current management is based on limited and generally low-quality evidence. We describe a statistical analysis plan (SAP) for the ACL SNNAP randomised controlled trial, which aims to investigate the necessity of surgical management in patients with ACL injuries.

Methods/design

ACL SNNAP is a pragmatic, multi-centre, superiority, parallel-group randomised controlled trial in participants with a symptomatic non-acute ACL deficient knee. Participants are allocated in a 1:1 ratio to either non-surgical management (rehabilitation) or surgical management (reconstruction) with the aim of assessing the efficacy and cost-effectiveness. The primary outcome of the study is the Knee Injury and Osteoarthritis Outcome Score (KOOS4) at 18 months post-randomisation. The KOOS4 score at 18 months will be evaluated using a linear regression model adjusting for recruitment centre and baseline KOOS4 scores, allowing for intra-centre correlation. A secondary analysis of the primary outcome will be carried out using an area under the curve (AUC) approach using treatment estimates obtained from a mixed model using baseline, 6 months, 12 months, and 18 months post-randomisation outcome data. Secondary outcomes will be measured at 18 months and will include return to activity/level of sport participation, intervention-related complications, the EQ-5D-5L questionnaire, all 5 individual subscales of the KOOS questionnaire, the ACL-QOL score, expectations of return to activity and cost-effectiveness of the interventions. Missing primary outcome data will be investigated through a sensitivity analysis. Full details of the planned methods for the statistical analysis of clinical outcomes are presented in this paper. The study protocol for the ACL SNNAP trial has been published previously.

Discussion

The methods of analysis for the ACL SNNAP trial have been described here to minimise the risk of data-driven results and reporting bias. Any deviations from the analysis methods described in this paper will be described in full and justified in the publications of the trial results.

Trial registration

ISRCTN ISRCTN10110685. Registered on 16 November 2016

Evaluation of placebo fidelity and trial design methodology in placebo-controlled surgical trials of musculoskeletal conditions: a systematic review

ABSTRACT

The number of placebo surgical trials on musculoskeletal conditions is increasing, but little is known about the quality of their design and methods. This review aimed to (1) assess the level of placebo fidelity (ie, degree to which the placebo control mimicked the index procedure) in placebo trials of musculoskeletal surgery, (2) describe the trials' methodological features using the adapted Applying Surgical Placebo in Randomised Evaluations (ASPIRE) checklist, and (3) describe each trial's characteristics. We searched 4 electronic databases from inception until February 18, 2021, for randomised trials of surgery that included a placebo control for any musculoskeletal condition. Protocols and full text were used to assess placebo fidelity (categorised as minimal, low, or high fidelity). The adapted 26-item ASPIRE checklist was also completed on each trial. PROSPERO registration number: CRD42021202131. A total of 30,697 studies were identified in the search, and 22 placebo-controlled surgical trials of 2045 patients included. Thirteen trials (59%) included a high-fidelity placebo control, 7 (32%) used low fidelity, and 2 (9%) minimal fidelity. According to the ASPIRE checklist, included trials had good reporting of the "rationale and ethics" (68% overall) and "design" sections (42%), but few provided enough information on the "conduct" (13%) and "interpretation and translation" (11%) of the placebo trials. Most trials sufficiently reported their rationale and ethics, but interpretation and translation are areas for improvement, including greater stakeholder involvement. Most trials used a high-fidelity placebo procedure suggesting an emphasis on blinding and controlling for nonspecific effects.

Minimal important changes and differences were estimated for Oxford hip and knee scores following primary and revision arthroplasty

OBJECTIVES

To create estimates for clinically meaningful changes and differences in pain and joint function for the Oxford Hip and Knee Scores (OHS/OKS) in primary and revision joint replacement.

STUDY DESIGN AND SETTING

694,487 primary and revision joint replacement procedures were analysed from the NHS PROMs dataset between 2012-2020. Minimal important changes (MIC) and differences (MID) were calculated using distribution and anchor-based methods (including receiver-operating characteristic (ROC) curve and predictive-modelling techniques).

RESULTS

For comparison of two or more groups (such as in a clinic trial), MID estimates were ∼5 points. For cohort studies investigating changes over time in a single group of patients, MIC_group estimates were 12.4 points (primary hip replacement), 8.6 points (revision hip replacement), 10.5 points (primary knee replacement) and 9.4 points (revision knee replacement). For studies investigating changes over time at the individual patient level, MIC_adjusted estimates were ∼8 points, ∼6 points, ∼7 points and ∼6 points respectively.

CONCLUSION

This study has calculated contemporary estimates of clinically important changes and differences for the OHS/OKS for primary and revision hip and knee replacement. These estimates can be used to inform sample size calculations and to interpret changes in joint function over time and differences between groups.

Unicompartmental compared with total knee replacement for patients with multimorbidities: a cohort study using propensity score stratification and inverse probability weighting

BACKGROUND

Although routine NHS data potentially include all patients, confounding limits their use for causal inference. Methods to minimise confounding in observational studies of implantable devices are required to enable the evaluation of patients with severe systemic morbidity who are excluded from many randomised controlled trials.

OBJECTIVES

Stage 1 - replicate the Total or Partial Knee Arthroplasty Trial (TOPKAT), a surgical randomised controlled trial comparing unicompartmental knee replacement with total knee replacement using propensity score and instrumental variable methods. Stage 2 - compare the risk benefits and cost-effectiveness of unicompartmental knee replacement with total knee replacement surgery in patients with severe systemic morbidity who would have been ineligible for TOPKAT using the validated methods from stage 1.

DESIGN

This was a cohort study.

SETTING

Data were obtained from the National Joint Registry database and linked to hospital inpatient (Hospital Episode Statistics) and patient-reported outcome data.

PARTICIPANTS

Stage 1 - people undergoing unicompartmental knee replacement surgery or total knee replacement surgery who met the TOPKAT eligibility criteria. Stage 2 - participants with an American Society of Anesthesiologists grade of ≥ 3.

INTERVENTION

The patients were exposed to either unicompartmental knee replacement surgery or total knee replacement surgery.

MAIN OUTCOME MEASURES

The primary outcome measure was the postoperative Oxford Knee Score. The secondary outcome measures were 90-day postoperative complications (venous thromboembolism, myocardial infarction and prosthetic joint infection) and 5-year revision risk and mortality. The main outcome measures for the health economic analysis were health-related quality of life (EuroQol-5 Dimensions) and NHS hospital costs.

RESULTS

In stage 1, propensity score stratification and inverse probability weighting replicated the results of TOPKAT. Propensity score adjustment, propensity score matching and instrumental variables did not. Stage 2 included 2256 unicompartmental knee replacement patients and 57,682 total knee replacement patients who had severe comorbidities, of whom 145 and 23,344 had linked Oxford Knee Scores, respectively. A statistically significant but clinically irrelevant difference favouring unicompartmental knee replacement was observed, with a mean postoperative Oxford Knee Score difference of < 2 points using propensity score stratification; no significant difference was observed using inverse probability weighting. Unicompartmental knee replacement more than halved the risk of venous thromboembolism [relative risk 0.33 (95% confidence interval 0.15 to 0.74) using propensity score stratification; relative risk 0.39 (95% confidence interval 0.16 to 0.96) using inverse probability weighting]. Unicompartmental knee replacement was not associated with myocardial infarction or prosthetic joint infection using either method. In the long term, unicompartmental knee replacement had double the revision risk of total knee replacement [hazard ratio 2.70 (95% confidence interval 2.15 to 3.38) using propensity score stratification; hazard ratio 2.60 (95% confidence interval 1.94 to 3.47) using inverse probability weighting], but half of the mortality [hazard ratio 0.52 (95% confidence interval 0.36 to 0.74) using propensity score stratification; insignificant effect using inverse probability weighting]. Unicompartmental knee replacement had lower costs and higher quality-adjusted life-year gains than total knee replacement for stage 2 participants.

LIMITATIONS

Although some propensity score methods successfully replicated TOPKAT, unresolved confounding may have affected stage 2. Missing Oxford Knee Scores may have led to information bias.

CONCLUSIONS

Propensity score stratification and inverse probability weighting successfully replicated TOPKAT, implying that some (but not all) propensity score methods can be used to evaluate surgical innovations and implantable medical devices using routine NHS data. Unicompartmental knee replacement was safer and more cost-effective than total knee replacement for patients with severe comorbidity and should be considered the first option for suitable patients.

FUTURE WORK

Further research is required to understand the performance of propensity score methods for evaluating surgical innovations and implantable devices.

TRIAL REGISTRATION

This trial is registered as EUPAS17435.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 66. See the NIHR Journals Library website for further project information.

Phase 3 Trials of Enhanced Versus Usual Care Physical Therapy for Patients at Risk of Poor Outcome Following Knee Arthroplasty: A Perspective on Meaning and a Way Forward

Physical therapy is routinely delivered to patients after discharge from the hospital following knee arthroplasty. Posthospitalization physical therapy is thought to be beneficial, particularly for those patients most at risk of poor outcome, the subgroup with persistent function-limiting pain, despite an apparently successful surgery. Research teams have undertaken 3 large-scale multicenter Phase 3 randomized clinical trials designed specifically for patients at risk of poor outcome following knee arthroplasty. All 3 trials screened for poor outcome risk using different methods and investigated different physical therapist interventions delivered in different ways. Despite the variety of types of physical therapy and mode of delivery, all trials found no effects of the enhanced treatment compared with usual care. In all cases, usual care required a lower dosage of physical therapy compared with the enhanced interventions. This Perspective compares and contrasts the 3 trials, speculates on factors that could explain the no-effect findings, and proposes areas for future study designed to benefit the poor outcome phenotype.

Total versus partial knee replacement in patients with medial compartment knee osteoarthritis: the TOPKAT RCT

BACKGROUND

Late-stage medial compartment knee osteoarthritis can be treated using total knee replacement or partial (unicompartmental) knee replacement. There is high variation in treatment choice and insufficient evidence to guide selection.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of partial knee replacement compared with total knee replacement in patients with medial compartment knee osteoarthritis. The findings are intended to guide surgical decision-making for patients, surgeons and health-care providers.

DESIGN

This was a randomised, multicentre, pragmatic comparative effectiveness trial that included an expertise component. The target sample size was 500 patients. A web-based randomisation system was used to allocate treatments.

SETTING

Twenty-seven NHS hospitals (68 surgeons).

PARTICIPANTS

Patients with medial compartment knee osteoarthritis.

INTERVENTIONS

The trial compared the overall management strategy of partial knee replacement treatment with total knee replacement treatment. No specified brand or subtype of implant was investigated.

MAIN OUTCOME MEASURES

The Oxford Knee Score at 5 years was the primary end point. Secondary outcomes included activity scores, global health measures, transition items, patient satisfaction (Lund Score) and complications (including reoperation, revision and composite 'failure' - defined by minimal Oxford Knee Score improvement and/or reoperation). Cost-effectiveness was also assessed.

RESULTS

A total of 528 patients were randomised (partial knee replacement, n = 264; total knee replacement, n = 264). The follow-up primary outcome response rate at 5 years was 88% and both operations had good outcomes. There was no significant difference between groups in mean Oxford Knee Score at 5 years (difference 1.04, 95% confidence interval -0.42 to 2.50). An area under the curve analysis of the Oxford Knee Score at 5 years showed benefit in favour of partial knee replacement over total knee replacement, but the difference was within the minimal clinically important difference [mean 36.6 (standard deviation 8.3) (n = 233), mean 35.1 (standard deviation 9.1) (n = 231), respectively]. Secondary outcome measures showed consistent patterns of benefit in the direction of partial knee replacement compared with total knee replacement although most differences were small and non-significant. Patient-reported improvement (transition) and reflection (would you have the operation again?) showed statistically significant superiority for partial knee replacement only, but both of these variables could be influenced by the lack of blinding. The frequency of reoperation (including revision) by treatment received was similar for both groups: 22 out of 245 for partial knee replacement and 28 out of 269 for total knee replacement patients. Revision rates at 5 years were 10 out of 245 for partial knee replacement and 8 out of 269 for total knee replacement. There were 28 'failures' of partial knee replacement and 38 'failures' of total knee replacement (as defined by composite outcome). Beyond 1 year, partial knee replacement was cost-effective compared with total knee replacement, being associated with greater health benefits (measured using quality-adjusted life-years) and lower health-care costs, reflecting lower costs of the index surgery and subsequent health-care use.

LIMITATIONS

It was not possible to blind patients in this study and there was some non-compliance with the allocated treatment interventions. Surgeons providing partial knee replacement were relatively experienced with the procedure.

CONCLUSIONS

Both total knee replacement and partial knee replacement are effective, offer similar clinical outcomes and have similar reoperation and complication rates. Some patient-reported measures of treatment approval were significantly higher for partial knee replacement than for total knee replacement. Partial knee replacement was more cost-effective (more effective and cost saving) than total knee replacement at 5 years.

FUTURE WORK

Further (10-year) follow-up is in progress to assess the longer-term stability of these findings.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN03013488 and ClinicalTrials.gov NCT01352247.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 20. See the NIHR Journals Library website for further project information.

Placebo comparator group selection and use in surgical trials: the ASPIRE project including expert workshop

BACKGROUND

The use of placebo comparisons for randomised trials assessing the efficacy of surgical interventions is increasingly being considered. However, a placebo control is a complex type of comparison group in the surgical setting and, although powerful, presents many challenges.

OBJECTIVES

To provide a summary of knowledge on placebo controls in surgical trials and to summarise any recommendations for designers, evaluators and funders of placebo-controlled surgical trials.

DESIGN

To carry out a state-of-the-art workshop and produce a corresponding report involving key stakeholders throughout.

SETTING

A workshop to discuss and summarise the existing knowledge and to develop the new guidelines.

RESULTS

To assess what a placebo control entails and to assess the understanding of this tool in the context of surgery is considered, along with when placebo controls in surgery are acceptable (and when they are desirable). We have considered ethics arguments and regulatory requirements, how a placebo control should be designed, how to identify and mitigate risk for participants in these trials, and how such trials should be carried out and interpreted. The use of placebo controls is justified in randomised controlled trials of surgical interventions provided that there is a strong scientific and ethics rationale. Surgical placebos might be most appropriate when there is poor evidence for the efficacy of the procedure and a justified concern that results of a trial would be associated with a high risk of bias, particularly because of the placebo effect.

CONCLUSIONS

The use of placebo controls is justified in randomised controlled trials of surgical interventions provided that there is a strong scientific and ethics rationale. Feasibility work is recommended to optimise the design and implementation of randomised controlled trials. An outline for best practice was produced in the form of the Applying Surgical Placebo in Randomised Evaluations (ASPIRE) guidelines for those considering the use of a placebo control in a surgical randomised controlled trial.

LIMITATIONS

Although the workshop participants involved international members, the majority of participants were from the UK. Therefore, although every attempt was made to make the recommendations applicable to all health systems, the guidelines may, unconsciously, be particularly applicable to clinical practice in the UK NHS.

FUTURE WORK

Future work should evaluate the use of the ASPIRE guidelines in making decisions about the use of a placebo-controlled surgical trial. In addition, further work is required on the appropriate nomenclature to adopt in this space.

FUNDING

Funded by the Medical Research Council UK and the National Institute for Health Research as part of the Medical Research Council-National Institute for Health Research Methodology Research programme.

Patient-Reported Function and Quality of Life After Revision Total Knee Arthroplasty: An Analysis of 10,727 Patients from the NHS PROMs Program

BACKGROUND

The aim of the study was to investigate changes in patient-reported outcome measures (PROMs) after revision total knee arthroplasty (rTKA).

METHODS

A total of 10,727 patients undergoing elective rTKA were recruited from the UK National Health Service PROMs data set from 2013 to 2019. PROMs were collected at baseline and six months to assess joint function (Oxford Knee Score, OKS) and quality of life (EQ-5D). Associations with a change in the OKS (COKS) were investigated through multiple linear regression.

RESULTS

The mean COKS was 12.4 (standard deviation 10.7) points. A total of 6776 of 10,329 (65.6%) patients demonstrated increase in the OKS above the minimal important change of 7.5 points. The median change in the EQ-5D utility was 0.227 (interquartile range 0.000 to 0.554). A total of 4917 of 9279 (53.0%) patients achieved a composite endpoint of improvement greater than the minimal important change for joint function and 'better' QoL as per the Paretian analysis. A total of 7477 of 10,727 (69.7%) patients reported satisfaction with rTKA. A total of 7947 of 10,727 (74.1%) patients felt surgery was a success. A total of 4888 of 10,632 (46.0%) patients reported one or more adverse events. A higher preoperative OKS was associated with a lower COKS (coefficient -0.63 [95% confidence interval -0.67 to -0.60]). Other factors associated with a lower COKS were postoperative complication(s), age under 60 years, longer duration of knee problems, patients who identified as disabled, problems in EQ-5D dimensions of anxiety/depression and self-care, comorbid conditions (circulatory problems, diabetes, and depression), and earlier year of procedure in the data set.

CONCLUSION

Two-thirds of patients experienced a meaningful improvement in joint function after rTKA. However, there was a high frequency of patient-reported complications. These findings may enable better informed discussion of the risks and benefits of discretionary rTKA.

Evidence for the validity of a patient-based instrument for assessment of outcome after revision knee arthroplasty

AIMS

To estimate the measurement properties for the Oxford Knee Score (OKS) in patients undergoing revision knee arthroplasty (responsiveness, minimal detectable change (MDC-90), minimal important change (MIC), minimal important difference (MID), internal consistency, construct validity, and interpretability).

METHODS

Secondary data analysis was performed for 10,727 patients undergoing revision knee arthroplasty between 2013 to 2019 using a UK national patient-reported outcome measure (PROM) dataset. Outcome data were collected before revision and at six months postoperatively, using the OKS and EuroQol five-dimension score (EQ-5D). Measurement properties were assessed according to COnsensus-based Standards for the selection of health status Measurement Instruments (COSMIN) guidelines.

RESULTS

A total of 9,219 patients had complete outcome data. Mean preoperative OKS was 16.7 points (SD 8.1), mean postoperative OKS 29.1 (SD 11.4), and mean change in OKS + 12.5 (SD 10.7). Median preoperative EQ-5D index was 0.260 (interquartile range (IQR) 0.055 to 0.691), median postoperative EQ-5D index 0.691 (IQR 0.516 to 0.796), and median change in EQ-5D index + 0.240 (IQR 0.000 to 0.567). Internal consistency was good with Cronbach's α 0.88 (baseline) and 0.94 (post-revision). Construct validity found a high correlation of OKS total score with EQ-5D index (r = 0.76 (baseline), r = 0.83 (post-revision), p < 0.001). The OKS was responsive with standardized effect size (SES) 1.54 (95% confidence interval (CI) 1.51 to 1.57), compared to SES 0.83 (0.81 to 0.86) for the EQ-5D index. The MIC for the OKS was 7.5 points (95% CI 5.5 to 8.5) based on the optimal cut-off with specificity 0.72, sensitivity 0.60, and area under the curve 0.66. The MID for the OKS was 5.2 points. The MDC-90 was 3.9 points. The OKS did not demonstrate significant floor or ceiling effects.

CONCLUSION

This study found that the OKS was a useful and valid instrument for assessment of outcome following revision knee arthroplasty. The OKS was responsive to change and demonstrated good measurement properties. Cite this article: Bone Joint J 2021;103-B(4):627-634.

Outpatient physiotherapy versus home-based rehabilitation for patients at risk of poor outcomes after knee arthroplasty: CORKA RCT

BACKGROUND

Over 100,000 primary knee arthroplasty operations are undertaken annually in the UK. Around 15-30% of patients do not report a good outcome. Better rehabilitation strategies may improve patient-reported outcomes.

OBJECTIVES

To compare the outcomes from a traditional outpatient physiotherapy model with those from a home-based rehabilitation programme for people assessed as being at risk of a poor outcome after knee arthroplasty.

DESIGN

An individually randomised, two-arm controlled trial with a blinded outcome assessment, a parallel health economic evaluation and a nested qualitative study.

SETTING

The trial took place in 14 NHS physiotherapy departments.

PARTICIPANTS

People identified as being at high risk of a poor outcome after knee arthroplasty.

INTERVENTIONS

A multicomponent home-based rehabilitation package delivered by rehabilitation assistants with supervision from qualified therapists compared with usual-care outpatient physiotherapy.

MAIN OUTCOME MEASURES

The primary outcome was the Late Life Function and Disability Instrument at 12 months. Secondary outcomes were the Oxford Knee Score (a disease-specific measure of function); Knee injury and Osteoarthritis Outcome Score; Quality of Life subscale; Physical Activity Scale for the Elderly; EuroQol-5 Dimensions, five-level version; and physical function assessed using the Figure-of-8 Walk Test, 30-Second Chair Stand Test and Single Leg Stance. Data on the use of health-care services, time off work and informal care were collected using participant diaries.

RESULTS

In total, 621 participants were randomised. A total of 309 participants were assigned to the COmmunity based Rehabilitation after Knee Arthroplasty (CORKA) home-based rehabilitation programme, receiving a median of five treatment sessions (interquartile range 4-7 sessions). A total of 312 participants were assigned to usual care, receiving a median of four sessions (interquartile range 2-6 sessions). The primary outcome, Late Life Function and Disability Instrument function total score at 12 months, was collected for 279 participants (89%) in the home-based CORKA group and 287 participants (92%) in the usual-care group. No clinically or statistically significant difference was found between the groups (intention-to-treat adjusted difference 0.49 points, 95% confidence interval -0.89 to 1.88 points; p = 0.48). There were no statistically significant differences between the groups in any of the patient-reported or physical secondary outcome measures at 6 or 12 months post randomisation. The health economic analysis found that the CORKA intervention was cheaper to provide than usual care (£66 less per participant). Total societal costs (combining health-care costs and other costs) were lower for the CORKA intervention than usual care (£316 less per participant). Adopting a societal perspective, CORKA had a 75% probability of being cost-effective at a threshold of £30,000 per quality-adjusted life-year. Adopting the narrower health and social care perspective, CORKA had a 43% probability of being cost-effective at the same threshold.

LIMITATIONS

The interventions were of short duration and were set within current commissioning guidance for UK physiotherapy. Participants and treating therapists could not be blinded.

CONCLUSIONS

This randomised controlled trial found no important differences in outcomes when post-arthroplasty rehabilitation was delivered using a home-based, rehabilitation assistant-delivered rehabilitation package or a traditional outpatient model. However, the health economic evaluation found that when adopting a societal perspective, the CORKA home-based intervention was cost-saving and more effective than, and thus dominant over, usual care, owing to reduced time away from paid employment for this group. Further research could look at identifying the risk of poor outcome and further evaluation of a cost-effective treatment, including the workforce model to deliver it.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13517704.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 65. See the NIHR Journals Library website for further project information.

Targeting rehabilitation to improve outcomes after total knee arthroplasty in patients at risk of poor outcomes: randomised controlled trial

OBJECTIVE

To evaluate whether a progressive course of outpatient physiotherapy offers superior outcomes to a single physiotherapy review and home exercise based intervention when targeted at patients with a predicted poor outcome after total knee arthroplasty.

DESIGN

Parallel group randomised controlled trial.

SETTING

13 secondary and tertiary care centres in the UK providing postoperative physiotherapy.

PARTICIPANTS

334 participants with knee osteoarthritis who were defined as at risk of a poor outcome after total knee arthroplasty, based on the Oxford knee score, at six weeks postoperatively. 163 were allocated to therapist led outpatient rehabilitation and 171 to a home exercise based protocol.

INTERVENTIONS

All participants were reviewed by a physiotherapist and commenced 18 sessions of rehabilitation over six weeks, either as therapist led outpatient rehabilitation (progressive goal oriented functional rehabilitation protocol, modified weekly in one-one contact sessions) or as physiotherapy review followed by a home exercise based regimen (without progressive input from a physiotherapist).

MAIN OUTCOME MEASURES

Primary outcome was Oxford knee score at 52 weeks, with a 4 point difference between groups considered to be clinically meaningful. Secondary outcomes included additional patient reported outcome measures of pain and function at 14, 26, and 52 weeks post-surgery.

RESULTS

334 patients were randomised. Eight were lost to follow-up. Intervention compliance was more than 85%. The between group difference in Oxford knee score at 52 weeks was 1.91 (95% confidence interval -0.18 to 3.99) points, favouring the outpatient rehabilitation arm (P=0.07). When all time point data were analysed, the between group difference in Oxford knee score was a non-clinically meaningful 2.25 points (0.61 to 3.90, P=0.01). No between group differences were found for secondary outcomes of average pain (0.25 points, -0.78 to 0.28, P=0.36) or worst pain (0.22 points, -0.71 to 0.41, P=0.50) at 52 weeks or earlier time points, or of satisfaction with outcome (odds ratio 1.07, 95% confidence interval 0.71 to 1.62, P=0.75) or post-intervention function (4.64 seconds, 95% confidence interval -14.25 to 4.96, P=0.34).

CONCLUSIONS

Outpatient therapist led rehabilitation was not superior to a single physiotherapist review and home exercise based regimen in patients at risk of poor outcomes after total knee arthroplasty. No clinically relevant differences were observed across primary or secondary outcome measures.

TRIALS REGISTRATION

Current Controlled Trials ISRCTN23357609 and ClinicalTrials.gov NCT01849445.

Varus alignment of the proximal tibia is associated with structural progression in early to moderate varus osteoarthritis of the knee

PURPOSE

Lower limb malalignment is a strong predictor of progression in knee osteoarthritis. The purpose of this study is to identify the individual alignment variables that predict progression in early to moderate osteoarthritis of the knee.

METHOD

A longitudinal cohort study using data from the Osteoarthritis Initiative. In total, 955 individuals (1329 knees) with early to moderate osteoarthritis (Kellgren-Lawrence grade 1, 2 or 3) were identified. All subjects had full-limb radiographs analysed using the Osteotomy module within Medicad^® Classic (Hectec GMBH) to give a series of individual alignment variables relevant to the coronal alignment of the lower limb. Logistic regression models, with generalised estimating equations were used to identify which of these individual alignment variables predict symptom worsening (WOMAC score > 9 points) and or structural progression (joint space narrowing progression in the medial compartment > 0.7mm) over 24 months.

RESULTS

Individual alignment variable were associated with both valgus and varus alignment (mechanical Lateral Distal Femoral Angle, Medial Proximal Tibial Angle and mechanical Lateral Distal Tibial Angle). Only the Medial Proximal Tibial Angle was significantly associated with structural progression and none of the variables was associated with symptom progression. The odds of joint space narrowing progression in the medial compartment occurring at 24 months increased by 21% for every one degree decrease (more varus) in Medial Proximal Tibial Angle (p < 0.001) CONCLUSIONS: Our results suggest that the risk of structural progression in the medial compartment is associated with greater varus alignment of the proximal tibia.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The use of patient-reported outcome measures to guide referral for hip and knee arthroplasty

AIMS

To calculate how the likelihood of obtaining measurable benefit from hip or knee arthroplasty varies with preoperative patient-reported scores.

METHODS

Existing UK data from 222,933 knee and 209,760 hip arthroplasty patients were used to model an individual's probability of gaining meaningful improvement after surgery based on their preoperative Oxford Knee or Hip Score (OKS/OHS). A clinically meaningful improvement after arthroplasty was defined as ≥ 8 point improvement in OHS, and ≥ 7 in OKS.

RESULTS

The upper preoperative score threshold, above which patients are unlikely to achieve any meaningful improvement from surgery, is 41 for knees and 40 for hips. At lower scores, the probability of improvement increased towards a maximum of 88% (knee) and 95% for (hips).

CONCLUSION

By our definition of meaningful improvement, patients with preoperative scores above 41 (OKS) and 40 (OHS) should not be routinely referred to secondary care for possible arthroplasty. Using lower thresholds would incrementally increase the probability of meaningful benefit for those referred but will exclude some patients with potential to benefit. The findings are useful to support the complex shared decision-making process in primary care for referral to secondary care; and in secondary care for experienced clinicians counselling patients considering knee or hip arthroplasty, but should not be used in isolation. Cite this article: Bone Joint J 2020;102-B(7):941-949.

Rates of knee arthroplasty in patients with a history of arthroscopic chondroplasty: results from a retrospective cohort study utilising the National Hospital Episode Statistics for England

OBJECTIVE

The purpose of this study was to analyse the rate of knee arthroplasty in the population of patients with a history of arthroscopic chondroplasty of the knee, in England, over 10 years, with comparison to general population data for patients without a history of chondroplasty.

DESIGN

Retrospective cohort study.

SETTING

English Hospital Episode Statistics (HES) data.

PARTICIPANTS AND INTERVENTIONS

Patients undergoing arthroscopic chondroplasty in England between 2007/2008 and 2016/2017 were identified. Patients undergoing previous arthroscopic knee surgery or simultaneous cruciate ligament reconstruction or microfracture in the same knee were excluded.

OUTCOMES

Patients subsequently undergoing a knee arthroplasty in the same knee were identified and mortality-adjusted survival analysis was performed (survival without undergoing knee arthroplasty). A Cox proportional hazards model was used to identify factors associated with knee arthroplasty. Relative risk of knee arthroplasty (total or partial) in comparison to the general population was determined.

RESULTS

Through 2007 to 2017, 157 730 eligible chondroplasty patients were identified. Within 1 year, 5.91% (7984/135 197; 95% CI 5.78 to 6.03) underwent knee arthroplasty and 14.22% (8145/57 267; 95% CI 13.94 to 14.51) within 5 years. Patients aged over 30 years with a history of chondroplasty were 17.32 times (risk ratio; 95% CI 16.81 to 17.84) more likely to undergo arthroplasty than the general population without a history of chondroplasty.

CONCLUSIONS

Patients with cartilage lesions of the knee, treated with arthroscopic chondroplasty, are at greater risk of subsequent knee arthroplasty than the general population and for a proportion of patients, there is insufficient benefit to prevent the need for knee arthroplasty within 1 to 5 years. These important new data will inform patients of the anticipated outcomes following this procedure. The risk in comparison to non-operative treatment remains unknown and there is an urgent need for a randomised clinical trial in this population.

Optimizing the design of invasive placebo interventions in randomized controlled trials

Background

Placebo‐controlled trials play an important role in the evaluation of healthcare interventions. However, they can be challenging to design and deliver for invasive interventions, including surgery. In‐depth understanding of the component parts of the treatment intervention is needed to ascertain what should, and should not, be delivered as part of the placebo. Assessment of risk to patients and strategies to ensure that the placebo effectively mimics the treatment are also required. To date, no guidance exists for the design of invasive placebo interventions. This study aimed to develop a framework to optimize the design and delivery of invasive placebo interventions in RCTs.

Methods

A preliminary framework was developed using published literature to: expand the scope of an existing typology, which facilitates the deconstruction of invasive interventions; and identify placebo optimization strategies. The framework was refined after consultation with key stakeholders in surgical trials, consensus methodology and medical ethics.

Results

The resulting DITTO framework consists of five stages: deconstruct treatment intervention into constituent components and co‐interventions; identify critical surgical element(s); take out the critical element(s); think risk, feasibility and role of placebo in the trial when considering remaining components; and optimize placebo to ensure effective blinding of patients and trial personnel.

Conclusion

DITTO considers invasive placebo composition systematically, accounting for risk, feasibility and placebo optimization. Use of the framework can support the design of high‐quality RCTs, which are needed to underpin delivery of healthcare interventions.

Considerations and methods for placebo controls in surgical trials (ASPIRE guidelines)

Placebo comparisons are increasingly being considered for randomised trials assessing the efficacy of surgical interventions. The aim of this Review is to provide a summary of knowledge on placebo controls in surgical trials. A placebo control is a complex type of comparison group in the surgical setting and, although powerful, presents many challenges. This Review outlines what a placebo control entails and present understanding of this tool in the context of surgery. We consider when placebo controls in surgery are acceptable (and when they are desirable) in terms of ethical arguments and regulatory requirements, how a placebo control should be designed, how to identify and mitigate risk for participants in these trials, and how such trials should be done and interpreted. Use of placebo controls is justified in randomised controlled trials of surgical interventions provided there is a strong scientific and ethical rationale. Surgical placebos might be most appropriate when there is poor evidence for the efficacy of the procedure and a justified concern that results of a trial would be associated with high risk of bias, particularly because of the placebo effect. Feasibility work is recommended to optimise the design and implementation of randomised controlled trials. This Review forms an outline for best practice and provides guidance, in the form of the Applying Surgical Placebo in Randomised Evaluations (known as ASPIRE) checklist, for those considering the use of a placebo control in a surgical randomised controlled trial.

Reporting of key methodological issues in placebo-controlled trials of surgery needs improvement: a systematic review

OBJECTIVES

To examine key methodological considerations for using a placebo intervention in randomized controlled trials (RCTs) evaluating invasive procedures, including surgery.

STUDY DESIGN AND SETTING

RCTs comparing an invasive procedure with a placebo were included in this systematic review. Articles published from database inception to December 31, 2017, were retrieved from Ovid MEDLINE, Ovid EMBASE and CENTRAL electronic databases, by handsearching references and expert knowledge. Data on trial characteristics (clinical area, nature of invasive procedure, number of patients and centers) and key methodological (rationale for using placebos, minimization of risk, information provision, offering the treatment intervention to patients randomized to placebo, delivery of cointerventions, and intervention standardization and fidelity) were extracted and summarized descriptively.

RESULTS

One hundred thirteen articles reporting 96 RCTs were identified. Most were conducted in gastrointestinal surgery (n = 40, 42%) and evaluated minimally invasive procedures (n = 44, 46%). Over two-thirds randomized fewer than 100 patients (n = 65, 68%) and a third were single center (n = 31, 32%). A third (n = 33, 34%) did not report a rationale for using a placebo. Most common strategies to minimize patient risk were operator skill (n = 22, 23%) and independent data monitoring (n = 28, 29%). Provision of patient information regarding placebo use was infrequently reported (n = 11, 11%). Treatment interventions were offered to patients randomized to placebo in 43 trials (45%). Cointerventions were inconsistently reported, but 64 trials (67%) stated that anesthesia was matched between groups. Attempts to standardize interventions and monitor their delivery were reported in n = 7, (7%) and n = 4, (4%) trials, respectively.

CONCLUSION

Most placebo-controlled trials in surgery evaluate minor surgical procedures and currently there is inconsistent reporting of key trial methods. There is a need for guidance to optimize the transparency of trial reporting in this area.

Rates of knee arthroplasty in anterior cruciate ligament reconstructed patients: a longitudinal cohort study of 111,212 procedures over 20 years

Background and purpose - Long-term rates of knee arthroplasty in patients with anterior cruciate ligament (ACL) injury who undergo ligament reconstruction (ACLr) are unclear. We determined this risk of arthroplasty through comparison with the general population.Patients and methods - All patients undergoing an ACLr in England, 1997-2017, were identified from national hospital statistics. Patients subsequently undergoing a knee arthroplasty were identified and survival analysis was performed (survival without undergoing knee arthroplasty). A Cox proportional hazards model was used to identify factors associated with knee arthroplasty. Relative risk of knee arthroplasty (total or partial) in comparison with the general population was determined.Results - 111,212 ACLr patients were eligible for analysis (mean age 29; 77% male). Overall, 0.46% (95% confidence interval [CI] 0.40-0.52) ACLr patients underwent knee arthroplasty within 5 years, 0.97% (CI 0.82-1.2) within 10 years, and 1.8% (CI 1.4-2.3) within 15 years. Knee arthroplasty risk was greater in older age groups and women. In comparison with the general population, the relative risk of undergoing arthroplasty at a younger age (at time of arthroplasty) was elevated: at 30-39 years (risk ratio [RR] 20; CI 11-35), 40-49 years (RR 7.5; CI 5.5-10), and 50-59 years (RR 2.5; CI 1.8-3.5), but not 60-69 years (RR 1.7; CI 0.93-3.2).Interpretation - Patients sustaining an ACL injury who undergo ACLr are at elevated risk of subsequent knee arthroplasty in comparison with the general population. Although the absolute rate of arthroplasty is low, the risk of arthroplasty at a younger age is particularly elevated. When the outcome of shared decision-making is ACLr, this data will help inform patients and clinicians about the long-term risk of requiring knee arthroplasty.

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

OBJECTIVE

The aim of this study was to determine the proportion of patients undergoing arthroscopic partial meniscectomy (APM) then subsequently receiving a knee arthroplasty within one or two years, with focus on patients over the age of 60 years and regional variation.

METHODS

Patients undergoing APM in England over 20-years (01-April-1997 to 31-March 2017) were identified in the national Hospital Episode Statistics (HES). The proportion of patients undergoing arthroplasty in the same knee within one or two years of APM was determined and trends were analysed over time nationally and by NHS Clinical Commissioning Group (CCG) region.

RESULTS

806,195 APM patients were eligible for analysis with at least one-year of follow up and 746,630 with two-years. The odds of arthroplasty conversion within one year increased over the study period (odds ratio [OR] 3.10 within 1-year in 2014 vs 2000; 95% confidence interval [CI] 2.75-3.50). For patients undergoing APM aged 60 years or older in 2015-16, 9.9% (1689/17,043; 95% CI 9.5-10.4) underwent arthroplasty within 1-year and, in 2014-15, 16.6% (3100/18,734; 95% CI 16.0-17.1) underwent arthroplasty within 2-years. There was greater than 10-fold variation by CCG.

CONCLUSIONS

Over the study period, the proportion of patients undergoing arthroplasty within one-year of APM increased. In 2015-16, of patients aged 60 years or older who underwent APM, 10% subsequently underwent knee arthroplasty within one year (17% within two years in 2014-15) and there was a high level of regional variation in this outcome. The development and adoption of national treatment guidance is recommended to improve and standardise treatment selection.

Rates of Adverse Outcomes and Revision Surgery After Anterior Cruciate Ligament Reconstruction: A Study of 104,255 Procedures Using the National Hospital Episode Statistics Database for England, UK

BACKGROUND

After an anterior cruciate ligament (ACL) injury, ACL reconstruction is an elective procedure, and therefore, an understanding of the attributable risk from undergoing ACL reconstruction is necessary for patients to make a fully informed treatment decision.

PURPOSE

To determine the absolute risk of adverse outcomes including reoperation after ACL reconstruction with comparison, where possible, to the rate of adverse events reported in the general population.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

National hospital data on all ACL reconstructions performed in England between April 1, 1997, and March 31, 2017, were analyzed. Revision cases, bilateral procedures within 6 months, and cases with concurrent cartilage or multiple ligament surgery were excluded. The primary outcome was the occurrence of at least 1 serious complication (myocardial infarction, stroke, pulmonary embolism, infection requiring surgery, fasciotomy, neurovascular injury, or death) within 90 days. Additionally, 5-year rates of revision ACL reconstruction, contralateral ACL reconstruction, and meniscal surgery were investigated.

RESULTS

There were 133,270 ACL reconstructions performed, of which 104,255 were eligible for analysis. Within 90 days, serious complications occurred in 675 (0.65% [95% CI, 0.60-0.70]), including 494 reoperations for infections (0.47% [95% CI, 0.43-0.52]) and 129 for pulmonary embolism (0.12% [95% CI, 0.10-0.15]). Of 54,275 procedures with at least 5 years' follow-up, 1746 (3.22% [95% CI, 3.07-3.37]) underwent revision ACL reconstruction in the same knee, 1553 underwent contralateral ACL reconstruction (2.86% [95% CI, 2.72-3.01]), and 340 underwent meniscal surgery (0.63% [95% CI, 0.56-0.70]). The overall risk of serious complications fell over time (adjusted odds ratio [OR], 0.96 per year [95% CI, 0.95-0.98]); however, older patients (adjusted OR, 1.11 per 5 years [95% CI, 1.07-1.16]) and patients with a greater modified Charlson Comorbidity Index (adjusted OR, 2.41 per 10 units [95% CI, 1.65-3.51]) were at a higher risk. For every 850 (95% CI, 720-1039) ACL reconstructions, 1 pulmonary embolism could be provoked. For every 213 (95% CI, 195-233), 1 native knee joint infection could be provoked.

CONCLUSION

The overall risk of adverse events after ACL reconstruction is low; however, some rare but serious complications, including infections or pulmonary embolism, may occur. Around 3% of patients undergo further ipsilateral or contralateral ACL reconstruction within 5 years. These data will inform shared decision making between clinicians and patients considering their treatment options.

Long-term rates of knee arthroplasty in a cohort of 834 393 patients with a history of arthroscopic partial meniscectomy

Aims

The aim of this study was to determine the long-term risk of undergoing knee arthroplasty in a cohort of patients with meniscal tears who had undergone arthroscopic partial meniscectomy (APM).

Patients and Methods

A retrospective national cohort of patients with a history of isolated APM was identified over a 20-year period. Patients with prior surgery to the same knee were excluded. The primary outcome was knee arthroplasty. Hazard ratios (HRs) were adjusted by patient age, sex, year of APM, Charlson comorbidity index, regional deprivation, rurality, and ethnicity. Risk of arthroplasty in the index knee was compared with the patient’s contralateral knee (with vs without a history of APM). A total of 834 393 patients were included (mean age 50 years; 37% female).

Results

Of those with at least 15 years of follow-up, 13.49% (16 256/120 493; 95% confidence interval (CI) 13.30 to 13.69) underwent subsequent arthroplasty within this time. In women, 22.07% (95% CI 21.64 to 22.51) underwent arthroplasty within 15 years compared with 9.91% of men (95% CI 9.71 to 10.12), corresponding to a risk ratio (RR) of 2.23 (95% CI 2.16 to 2.29). Relative to the general population, patients with a history of APM were over ten times more likely (RR 10.27; 95% CI 10.07 to 10.47) to undergo arthroplasty rising to almost 40 times more likely (RR 39.62; 95% CI 27.68 to 56.70) at a younger age (30 to 39 years). In patients with a history of APM in only one knee, the risk of arthroplasty in that knee was greatly elevated in comparison with the contralateral knee (no APM; HR 2.99; 95% CI 2.95 to 3.02).

Conclusion

Patients developing a meniscal tear undergoing APM are at greater risk of knee arthroplasty than the general population. This risk is three-times greater in the patient’s affected knee than in the contralateral knee. Women in the cohort were at double the risk of progressing to knee arthroplasty compared with men. These important new reference data will inform shared decision making and enhance approaches to treatment, prevention, and clinical surveillance. Cite this article: Bone Joint J 2019;101-B:1071–1080.

The clinical and cost-effectiveness of total versus partial knee replacement in patients with medial compartment osteoarthritis (TOPKAT): 5-year outcomes of a randomised controlled trial

BACKGROUND

Late-stage isolated medial knee osteoarthritis can be treated with total knee replacement (TKR) or partial knee replacement (PKR). There is high variation in treatment choice and little robust evidence to guide selection. The Total or Partial Knee Arthroplasty Trial (TOPKAT) therefore aims to assess the clinical effectiveness and cost-effectiveness of TKR versus PKR in patients with medial compartment osteoarthritis of the knee, and this represents an analysis of the main endpoints at 5 years.

METHODS

Our multicentre, pragmatic randomised controlled trial was done at 27 UK sites. We used a combined expertise-based and equipoise-based approach, in which patients with isolated osteoarthritis of the medial compartment of the knee and who satisfied general requirements for a medial PKR were randomly assigned (1:1) to receive PKR or TKR by surgeons who were either expert in and willing to perform both surgeries or by a surgeon with particular expertise in the allocated procedure. The primary endpoint was the Oxford Knee Score (OKS) 5 years after randomisation in all patients assigned to groups. Health-care costs (in UK 2017 prices) and cost-effectiveness were also assessed. This trial is registered with ISRCTN (ISRCTN03013488) and ClinicalTrials.gov (NCT01352247).

FINDINGS

Between Jan 18, 2010, and Sept 30, 2013, we assessed 962 patients for their eligibility, of whom 431 (45%) patients were excluded (121 [13%] patients did not meet the inclusion criteria and 310 [32%] patients declined to participate) and 528 (55%) patients were randomly assigned to groups. 94% of participants responded to the follow-up survey 5 years after their operation. At the 5-year follow-up, we found no difference in OKS between groups (mean difference 1·04, 95% CI -0·42 to 2·50; p=0·159). In our within-trial cost-effectiveness analysis, we found that PKR was more effective (0·240 additional quality-adjusted life-years, 95% CI 0·046 to 0·434) and less expensive (-£910, 95% CI -1503 to -317) than TKR during the 5 years of follow-up. This finding was a result of slightly better outcomes, lower costs of surgery, and lower follow-up health-care costs with PKR than TKR.

INTERPRETATION

Both TKR and PKR are effective, offer similar clinical outcomes, and result in a similar incidence of re-operations and complications. Based on our clinical findings, and results regarding the lower costs and better cost-effectiveness with PKR during the 5-year study period, we suggest that PKR should be considered the first choice for patients with late-stage isolated medial compartment osteoarthritis.

FUNDING

National Institute for Health Research Health Technology Assessment Programme.

Surgical interventions for symptomatic mild to moderate knee osteoarthritis

BACKGROUND

Osteoarthritis affecting the knee is common and represents a continuum of disease from early cartilage thinning to full-thickness cartilage loss, bony erosion, and deformity. Many studies do not stratify their results based on the severity of the disease at baseline or recruitment.

OBJECTIVES

To assess the benefits and harms of surgical intervention for the management of symptomatic mild to moderate knee osteoarthritis defined as knee pain and radiographic evidence of non-end stage osteoarthritis (Kellgren-Lawrence grade 1, 2, 3 or equivalent on MRI/arthroscopy). Outcomes of interest included pain, function, radiographic progression, quality of life, short-term serious adverse events, re-operation rates and withdrawals due to adverse events.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase up to May 2018. We also conducted searches of ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform for ongoing trials. Authors of trials were contacted if some but not all their participants appeared to fit our inclusion criteria.

SELECTION CRITERIA

We included randomised controlled trials that compared surgery to non-surgical interventions (including sham and placebo control groups, exercise or physiotherapy, and analgesic or other medication), injectable therapies, and trials that compared one type of surgical intervention to another surgical intervention in people with symptomatic mild to moderate knee osteoarthritis.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials and extracted data using standardised forms. We analysed the quality of evidence using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) approach.

MAIN RESULTS

A total of five studies involving 566 participants were identified as eligible for this review. Single studies compared arthroscopic partial meniscectomy to physical therapy (320 participants), arthroscopic surgery (debridement ± synovectomy ± chondroplasty) to closed needle joint lavage with saline (32 participants) and high tibial osteotomy surgery to knee joint distraction surgery (62 participants). Two studies (152 participants) compared arthroscopic surgery (washout ± debridement; debridement) to a hyaluronic acid injection. Only one study was at low risk of selection bias, and due to the difficulty of blinding participants to their treatment, all studies were at risk of performance and detection bias.Reporting of results in this summary has been restricted to the primary comparison: surgical intervention versus non-surgical intervention.A single study, included 320 participants with symptoms consistent with meniscal tear. All subjects had the meniscal tear confirmed on knee MRI and radiographic evidence of mild to moderate osteoarthritis (osteophytes, cartilage defect or joint space narrowing). Patients with severe osteoarthritis (KL grade 4) were excluded. The study compared arthroscopic partial meniscectomy and physical therapy to physical therapy alone (a six-week individualised progressive home exercise program). This study was at low risk of selection bias and outcome reporting biases, but was susceptible to performance and detection biases. A high rate of cross-over (30.2%) occurred from the physical therapy group to the arthroscopic group.Low-quality evidence suggests there may be little difference in pain and function at 12 months follow-up in people who have arthroscopic partial meniscectomy and those who have physical therapy. Evidence was downgraded to low quality due to risk of bias and imprecision.Mean pain was 19.3 points on a 0 to 100 point KOOS pain scale with physical therapy at 12 months follow-up and was 0.2 points better with surgery (95% confidence interval (CI) 4.05 better to 3.65 points worse with surgery, an absolute improvement of 0.2% (95% CI 4% better to 4% worse) and relative improvement 0.4% (95% CI 9% better to 8% worse) (low quality evidence). Mean function was 14.5 on a 0 to 100 point KOOS function scale with physical therapy at 12 months follow-up and 0.8 points better with surgery (95% CI 4.3 better to 2.7 worse); 0.8% absolute improvement (95% CI 4% better to 3% worse) and 2.1% relative improvement (95% CI 11% better to 7% worse) (low quality evidence).Radiographic structural osteoarthritis progression and quality of life outcomes were not reported.Due to very low quality evidence, we are uncertain if surgery is associated with an increased risk of serious adverse events, incidence of total knee replacement or withdrawal rates. Evidence was downgraded twice due to very low event rates, and once for risk of bias.At 12 months, the surgery group had a total of three serious adverse events including fatal pulmonary embolism, myocardial infarction and hypoxaemia. The physical therapy alone group had two serious adverse events including sudden death and stroke (Peto OR 1.58, 95% CI 0.27 to 9.21); 1% more events with surgery (95% CI 2% less to 3% more) and 58% relative change (95% CI 73% less to 821% more). One participant in each group withdrew due to adverse events.Two of 164 participants (1.2%) in the physical therapy group and three of 156 in the surgery group underwent conversion to total knee replacement within 12 months (Peto OR 1.76, 95% CI 0.43 to 7.13); 1% more events with surgery (95% CI 2% less to 5% more); 76% relative change (95% CI 57% less to 613% more).

AUTHORS' CONCLUSIONS

The review found no placebo-or sham-controlled trials of surgery in participants with symptomatic mild to moderate knee osteoarthritis. There was low quality evidence that there may be no evidence of a difference between arthroscopic partial meniscectomy surgery and a home exercise program for the treatment of this condition. Similarly, low-quality evidence from a few small trials indicates there may not be any benefit of arthroscopic surgery over other non-surgical treatments including saline irrigation and hyaluronic acid injection, or one type of surgery over another. We are uncertain of the risk of adverse events or of progressing to total knee replacement due to very small event rates. Thus, there is uncertainty around the current evidence to support or oppose the use of surgery in mild to moderate knee osteoarthritis. As no benefit has been demonstrated from the low quality trials included in this review, it is possible that future higher quality trials for these surgical interventions may not contradict these results.

Arthroscopic meniscal surgery: a national society treatment guideline and consensus statement

AIMS

The aim of the British Association for Surgery of the Knee (BASK) Meniscal Consensus Project was to develop an evidence-based treatment guideline for patients with meniscal lesions of the knee.

MATERIALS AND METHODS

A formal consensus process was undertaken applying nominal group, Delphi, and appropriateness methods. Consensus was first reached on the terminology relating to the definition, investigation, and classification of meniscal lesions. A series of simulated clinical scenarios was then created and the appropriateness of arthroscopic meniscal surgery or nonoperative treatment in each scenario was rated by the group. The process was informed throughout by the latest published, and previously unpublished, clinical and epidemiological evidence. Scenarios were then grouped together based upon the similarity of clinical features and ratings to form the guideline for treatment. Feedback on the draft guideline was sought from the entire membership of BASK before final revisions and approval by the consensus group.

RESULTS

A total of 45 simulated clinical scenarios were refined to five common clinical presentations and six corresponding treatment recommendations. The final guideline stratifies patients based upon a new, standardized classification of symptoms, signs, radiological findings, duration of symptoms, and previous treatment.

CONCLUSION

The 2018 BASK Arthroscopic Meniscal Surgery Treatment Guidance will facilitate the consistent identification and treatment of patients with meniscal lesions. It is hoped that this guidance will be adopted nationally by surgeons and help inform healthcare commissioning guidance. Validation in clinical practice is now required and several areas of uncertainty in relation to treatment should be a priority for future high-quality prospective studies. Cite this article: Bone Joint J 2019;101-B:652-659.