Title: COmmunity based Rehabilitation after Knee Arthroplasty (CORKA)
Funder: Department of Health and Social Care

Abstract: Design: A two stage study is proposed. Firstly, we will perform analysis of factors associated with poor outcome to develop a screening algorithm. Methods to identify people at high risk are uncertain, but general principles of older people with generalised frailty and significant global function / cognitive impairment prior to surgery are widely accepted using the principles of the American Geriatric Society Best Practice Guidelines for Pre-operative Assessment of Geriatric Surgical Patients (2012). We aim to identify patients at risk of poor outcome based upon these principles using 2 methods: 1. We will systematically review the literature and use expert opinion from an online survey of rehabilitation clinicians to identify factors associated with poor outcome after knee arthroplasty. 2. We will examine data from a large study cohort of patients from the COAST study - a NIHR funded study to assess outcome following lower limb joint arthroplasty. In the second stage we will conduct a prospective individually randomised single blinded two arm RCT. Patients deemed at risk of poor outcome will receive a targeted rehabilitation intervention delivered in their own homes. Setting: Recruitment from a minimum of 6 orthopaedic hubs and their surrounding physiotherapy providers, each main hub performing> 300 knee arthroplasty operations / year, geographically spread around the UK. Interventions to be delivered in the patients home for intervention arm and out-patient physiotherapy clinic for control arm. Target Population: Patients undergoing TKR assessed using screening algorithm as at risk of poor outcome Health Technology being assessed: Physiotherapy and Occupational therapy – Occupational therapy will focus on pre-operative assessment and adaptations to patients’ homes to enable a safe environment for home exercise and everyday functional tasks. Physiotherapy will include home based intervention with an emphasis on a functional activity based programme. We will test if the intervention can be delivered by generic rehabilitation therapists, rather than uni-professionally. Intervention: A multi-component rehabilitation programme. The majority component will be an exercise based exercise programme to be delivered in the patients’ own homes. Attention will also be paid to pain management, confidence building, appropriate provision of aids and appliances and suitability of the lay out of the home environment. The exercise component will include assessment of current functional level and gait re-education, progression/removal of walking aids, plus a programme of exercises to mobilise and strengthen. Repetition rate, frequency and progression of exercises will be left to the physiotherapist’s discretion. Task training will be included: getting in/out of a car. We plan to include use of rehabilitation assistants to assist with the delivery of the intervention, an approach that has been successful in other community based therapy trials Attention will be paid to the interface with other members of the primary care health team such as district nursing, health visiting and community social services, to ensure appropriate awareness and reinforcement of the rehabilitation strategy and programme. The programme will focus on both improving functional outcome but also participation levels. Control: Normal care as is currently provided, i.e. written advice and a home exercise programme on discharge from hospital and up to 6 sessions of traditional out-patient physiotherapy. A qualitative study using an interpretative phenomenological analysis approach will be incorporated to explore the experiences and views of patients about the treatment interventions. Measurement of cost and outcomes: Outcome measures will be collected at baseline, 6 months, 12 months and 24 Months (Approx only 326 participants will have 24 month data collected). Primary outcome: Late Life Function and Disability Instrument. It is an outcome instrument developed specifically for community-dwelling older adults, which assesses and responds to meaningful change in two distinct outcomes: function (a person's ability to do discrete actions or activities), and disability (a person's performance of socially defined life tasks). There is a 16-item disability component and a 32-item function component. Secondary Measures: We will measure disease specific function by the Oxford Knee Score and quality of life by the subscale of the Knee Osteoarthritis Outcome Score (KOOS). Activity will be measured by Physical Activity Scale for the Elderly (PASE) questionnaire. Physical function will be measured by a physical performance tasks – the Timed Up and Go, figure of 8 walk test and a step climb test. Pain will be measured using VAS and health economics using EQ5D-5L and a patient diary. We will conduct a cost utility analysis from both NHS and a societal perspective. Sample Size: Using the LLFDI as our primary outcome the sample size calculation is based on a moderately small standardised effect size of 0.25, which is a value that we expect to be clinically important and realistic in rehabilitation trials. Assuming SMD of 0.275 or 3 points in the LLFDI we would need a total sample size of 568, needing to recruit 620 at 90% power and 5% level of significant (2-sided) and loss to follow up rate is 10%. Health Economics: A participant diary will record use of healthcare, medication, exercise undertaken and any adverse events. We will collect health utility data from EQ5D-5L to calculate QALYs and cost data from participant completed diaries to conduct a cost utility analysis from both NHS and a societal perspective.

Lay abstract: Summary (in Plain English) The number of knee replacements taking place in the UK is continuing to rise; over 84,000 knee replacements took place in the UK during 2011 which is an increase of > 3% from 2010. Part of the reason for this increase is that knee replacements are increasingly being performed for patients who are older and with other health conditions in addition to their osteoarthritis. It is known that age is not a barrier to having a good outcome from knee replacement, with reports of successful outcome in patients aged over 90 years. However, it is also known that around 15% of patients do not report a good outcome from their knee replacement and have continuing pain and mobility problems which limit or prevent them from being able to do the activities they would like to be able to do after their knee replacement. It is thought that factors such as the amount of pain and limitation of balance and muscle strength may contribute to poorer outcome. Currently it is normal practice for patients to receive a short course (between 4-6 sessions) of post-operative physiotherapy after their surgery. This is usually delivered in a physiotherapy out-patient clinic setting. Previous research has shown that this short course of physiotherapy is not needed by all patients to help them recover after their operation. Given the increasing number of knee replacements, the relative limited physiotherapy resource available and the increasing age and frailty of patients receiving joint replacements, it is important that we concentrate our rehabilitation resources on those patients who most need help to avoid poor outcome. We plan to run a study in two stages. In the first we aim to identify patients at risk of poor outcome using 2 methods: 1. We will systematically review the literature and use expert opinion from an online survey of rehabilitation clinicians to identify factors associated with poor outcome after knee arthroplasty. 2. We will examine data from a large study cohort of patients from the COAST study - a NIHR funded study to assess outcome following lower limb joint arthroplasty. We will analyse all the information obtained both before people have their joint replacements and the information about their outcomes and 12 months after joint replacement. Using these sources of information we will develop a screening tool that will help us to identify those patients who are most at risk of poor outcome i.e. those patients who are most likely to have continuing pain and mobility problems and who are limited or unable to return to doing the activities they would like to be able to after their joint replacement. Secondly, we will develop and test a multidisciplinary rehabilitation exercise intervention designed to improve both the function of ‘at risk’ patients, but also their participation in activities. We aim to deliver this intervention in patients’ own homes in order to make it accessible to those without good social support or those with physical or mental frailty. In order to make the intervention affordable to the NHS, we will use a combination of qualified physiotherapists, occupational therapists and rehabilitation assistants to deliver the intervention. The use of rehabilitation assistants to supervise and facilitate exercise under the guidance of qualified staff will be piloted to test the skills required to implement an exercise based programme that is affordable. This approach has been used successfully in other trials of therapy such as after hip fracture and in speech therapy after stroke. We will compare this new intervention with normal care as is currently provided. Both arms of the trial will receive the same treatment whilst in hospital and the same advice about exercise on discharge. Those in the normal care arm would receive standard post-operative care which may include out-patient physiotherapy; those in the intervention arm will receive a home based exercise programme. We will measure patients’ progress at 6 months, 12 months and 24 (Approx only 326 participants will have 24 month data collected) months after their surgery. We will use a number of established outcome measures to assess whether this new intervention improves patient’s functional abilities, quality of life, their level of functional ability and their taking part in social activities. We will use information from diaries kept by patients about their visits to their GP, District nurse, physiotherapy, occupational therapy, any hospital visits and medication and equipment to perform an economic analysis about the costs and benefits of the new intervention compared to usual care. To find out what makes the proposed intervention acceptable and patients willing to participate and adhere to the treatment programme it is important to ask people about their experiences of taking part. This is called ‘qualitative research’ and is widely used to improve the quality of health care that we provide. Understanding why patients and their carers make decisions about their health care, and particularly about the ease or burden of exercise is important if we are to devise acceptable and effective treatment programmes. We will do this by interviewing patients, carers and therapists to gain their perspectives about our intervention. Patients will be asked to voluntarily participate in the study and may withdraw at any time. We do not foresee any ethical concerns with our proposal. As a team, we have considerable expertise in conducting trials of complex rehabilitation interventions. We have previously conducted trials with patients with hip replacements, osteoarthritis of the knee, back surgery, back pain and hand arthritis. We have costed the trial prudently to enable the objectives of the study to be met in the timescale proposed, whilst being aware of the cost to the public purse of such research.

Research activity codes: 5.7 PHYSICAL;6.7 PHYSICAL
Health categories: MUSCULOSKELETAL