Title: Improving outcomes for patients with hip osteoarthritis: a randomised controlled trial
Funder: Department of Health and Social Care

Abstract: Background Osteoarthritis, the commonest chronic disease managed in primary care, causes pain, disability and poor health related quality of life. Treatments aim to reduce symptoms and prevent disease progression. The burden of hip osteoarthritis is substantial and increasing with our ageing and inactive population (Woolf,2003). More than one in four people develop hip osteoarthritis by age 85 (Murphy,2010) and whilst more than 72,000 people have total hip replacements in the UK, only the minority of patients will need this intervention (Lievense,2007). Patients with osteoarthritis often have suboptimal management (McHugh,2012, Steel,2008), especially those with more severe disease, who feel their pain is neglected in primary care (McHugh,2011). A range of treatments are available, including exercise and analgesia, although evidence supporting their use, especially in primary care, is limited. One treatment that can be used is intra-articular corticosteroid injection. This is typically administered together with a local anaesthetic, and using ultrasound-guidance to improve accuracy (Berkoff,2012). A recent systematic review (Zhang,2007) identified 4 studies assessing the efficacy of corticosteroid injection of the hip. The findings were conflicting, with the authors recommending further research. Since the review publication several small trials (Atchia,2011, Robinson,2007, Micu,2010) have been published adding further support to using intra-articular corticosteroid injections to relieve pain. However, these trials are limited; with small sample sizes and short-term follow-up, selecting patients from secondary care who typically have more severe symptoms. Further evidence is needed to support their use in primary care patients. Our proposed trial will investigate the clinical and cost-effectiveness of a corticosteroid and lidocaine injection for patients with hip osteoarthritis (versus best current practice). Furthermore, by including an intervention arm consisting of lidocaine injection alone we will explore whether any given effect can be attributed to the specific effect of the corticosteroid or whether it is likely to represent the non-specific effects of receiving an injection. Investigation plan GPs, prompted by an electronic pop-up , will refer patients with hip osteoarthritis to clinics where they will be assessed for eligibility. Hip OA will be confirmed using plain radiography. Participants interested in the trial will be given a second appointment at the hip clinic to determine participation, obtain written consent and conduct a baseline research assessment and receive the intervention. Participants will be randomised to one of three treatment groups as follows: Best current practice + ultrasound-guided intra-articular corticosteroid and 1% lidocaine injection Best current practice + ultrasound-guided intra-articular 1% lidocaine injection Best current practice Outcomes will be measured before randomisation at the research clinic and at 2 and 6 weeks, 3 and 6 months by postal questionnaire. The primary outcome measure is the numerical rating scale (0-10) score for worst pain in the last week. Potential adverse effects will be closely monitored in conjunction with the standardised operating procedures established by our registered CTU. Analysis will be based on comparisons of participants average follow-up pain NRS scores, based on a random effects linear repeated-measures model, with a cluster size of 4 (denoting 4 follow up assessments) and a postulated coefficient of 0.5. A sample size of 232 will provide 80% power (5% two-tailed significance) to detect a minimum difference of 1.5 points in the change of the pain NRS score (maximum SD of change = 4.5 points; effect size of 0.33) between best current practice plus corticosteroid and 1% lidocaine injection and best current practice alone across the 6-month follow-up period, allowing for total of 15% loss to follow-up. As our trial will also compare best current practice plus 1% lidocaine injection with best current practice alone, we have three groups of interest and hence need 348 participants.

Lay abstract: Hip osteoarthritis common, causing significant pain, disability and reduced quality of life. It is usual managed by GPs; only a small proportion of patients access secondary care treatments including total hip replacements. Whilst a range of treatments are recommended, the evidence-base supporting their use in primary care is limited. Hip joint injections are increasingly used as a treatment for hip osteoarthritis but their effectiveness for primary care patients is unclear. A systematic review identified only 4 studies testing the benefit of corticosteroid injection for hip osteoarthritis. The findings were conflicting and further research recommended. More recent studies reported benefits from injection, but were conducted with predominantly secondary care patient groups (who tend to have more severe problems) and only assessed short-term outcomes after the injection. Furthermore, it is uncertain whether any given effect can be attributed to the specific effect of the corticosteroid or if it is related to non-specific effects of receiving an injection. This new trial tests the clinical and cost-effectiveness of intra-articular corticosteroid and 1% lidocaine injection in patients with hip osteoarthritis from primary care. GPs will refer patients with hip osteoarthritis to a primary care hip clinic where they will be assessed for suitability for inclusion in this trial. 348 eligible patients (the largest number of any hip injection trial to date) will be randomised to one of three treatments: 1:Best current practice and ultrasound-guided intra-articular corticosteroid and 1% lidocaine injection 2:Best current practice and ultrasound-guided intra-articular 1% lidocaine injection 3:Best current practice alone Clinicians will be trained by local experts to deliver intra-articular injections, given using ultrasound-guidance, in line with best current practice. Participants will complete questionnaires in the research clinic and then postally at 2 weeks, 6 weeks, 3 months and 6 months to determine the short and longer term effects of the treatments.

Research activity codes: 6.1 PHARMACEUTICALS
Health categories: MUSCULOSKELETAL