Title: Short: The ACL SNNAP Trial: Anterior Cruciate Ligament Surgery Necessity in Non Acute Patients Long: Comparison of the clinical and cost effectiveness of two management strategies for non-acute Anterior Cruciate Ligament (ACL) injury: Rehabilitation versus surgical Reconstruction
Funder: Department of Health and Social Care

Abstract: Background Rupture of the Anterior Cruciate Ligament (ACL) is common but the resulting disability can be variable. Some patients recover and cope fine without their ACL. Others do not recover as well and continue to have episodes of knee instability/giving way affecting daily activities, work and recreation. It is often thought that these patients require surgery (ACL reconstruction) to stabilise the knee. In the NHS it is estimated at least 14,000 primary ACL reconstructions are performed each year) but other evidence suggests the frequency may be much greater (possibly up to 40,000 pa). Based on the conservative estimates the costs of ACLR to the NHS will be approximately £60 million for 2015 (each operation and post op care = £3800). The effect of the injury is variable - being neither consistent nor predictable. This means that clinical management varies from surgeon to surgeon and from hospital to hospital. Some surgeons feel that patients should always undergo surgery (ACL reconstruction), and as soon as possible after being diagnosed. The rationale is that by surgically stabilising an unstable knee, further internal damage (of the cartilage) can be prevented and improve a patient’s long term outcome. Conversely some surgeons feel that a period of rehabilitation (exercises) should always be prescribed as it may be possible to avoid an operation altogether. Recent work in Scandinavia (Frobell et al, 2010) has shown that rehabilitation of patients with acute ACL can reduce the number of surgical reconstructions by 50% without compromising outcome. Unfortunately, because these patients were recently injured (acute) the results cannot be extrapolated to the NHS. NHS patients are not routinely seen within the acute phase and clinical management plans are often initiated between 4 and 12 months after the initial injury. The delay introduces an element of screening and self-selection. Those patients that are likely to “cope” without their ligament and benefit from remedial exercises are likely to be already doing so and will not present to secondary care. The benefits for either management approach are uncertain and therefore a new study is required to discover the best treatment option. Aims To determine, in patients with non-acute Anterior Cruciate Ligament Deficiency (ACLD), whether non-surgical treatment (with the option for later ACL reconstruction if required) is more effective than surgical ACL reconstruction as measured by the Knee Injury and Osteoarthritis Outcome Score [KOOS4] at 18 months from randomisation. Method Design: Multi-centre superiority 2 arm parallel group design RCT with 1:1 allocation. Setting: 320 patients recruited from 20 NHS orthopaedic units over 2 years. Target population: Patients >18yrs with symptomatic ACLD confirmed using clinical assessment and MRI scan. Health technologies assessed: Comparison of two routine NHS management strategies for patients with non-acute ACLD knees: a) non-surgical management [Rehabilitation] b) surgical management [Reconstruction]. Outcomes: Primary: KOOS4 score at 18 months post randomisation. The score is derived from 4 of the 5 KOOS subscales; pain, symptoms, difficulty in sports and recreational activities, and knee related quality of life. Secondary: return to sport/activity, complications, patient satisfaction, expectations of activity, generic health related quality of life (EQ-5D-5L), and health care, non-health care, and productivity costs for both management strategies to 18 months. Inclusion Criteria: Patients >18yrs with symptomatic ACL deficiency confirmed by clinical assessment and MRI scan. Exclusion Criteria: Less than 4 months since injury, previous knee surgery to study (index) knee (except diagnostic arthroscopy), meniscal pathology sufficiently symptomatic to require surgery i.e. locked knee, large bucket handle tear, knee joint status arthritic (grade 3 or 4 on the Kellgren and Lawrence scale), grade 3 MCL/LCL injury, PCL/PLC injury, inflammatory arthropathy, pregnancy. An internal recruitment pilot is planned. Progression criteria are a minimum of 25 patients within 6 months and 94 patients within 1 year of starting recruitment.

Lay abstract: The aim is to determine the best treatment for people rupturing an important knee ligament, the Anterior Cruciate Ligament (ACL). This common injury causes physical giving way of the knee and/or sensations of it being wobbly (instability). The instability is often serious enough to affect day to day activities, work and recreation. There are two main NHS treatment options for this problem, non-surgical treatment using physiotherapy or an operation to replace the ligament (ACL reconstruction). A special review (Cochrane) of existing research confirmed there are virtually no studies to show which management strategy is best. This lack of research means that treatment varies between surgeons and hospitals. Some doctors feel that all patients should undergo surgery and as soon as possible to stabilise the joint, prevent buckling and stop any further damage. At least 13,941 of these operations were performed in the UK last year (although other records suggest a figure closer to 50,000). The costs of ACL surgery to the NHS amount to about £60 million per year. Others feel that blanket referral for operative treatment is controversial as surgery may not always be necessary. It is known that a stable knee can be achieved in many patients by using physiotherapy exercises. Some therefore feel that a rehabilitation programme should always be tried first before considering surgery. We do have evidence (a single Scandinavian study) to show that a rehabilitation strategy can be successful. Up to 50% of newly injured ACL patients were found to achieve good function and avoid surgery by first trying physiotherapy. However, this study involved newly injured patients only and not those with longer-standing injury (non-acute) often seen in the NHS. As a consequence this research has not changed practice in the UK. The preferred management remains surgery, with 80% of injured patients undergoing ACL reconstruction. Overall, NHS treatment for the ACL injured knee is very mixed and poorly justified. Surgery can be successful but it could be argued that all NHS patients should be first prescribed physiotherapy to potentially avoid surgery. As the relative benefit for each management strategy is unknown, a study is needed to show which is best. A clinical trial of 320 ACL injured patients from 20 NHS hospitals will compare these two treatment strategies for non-acute ACL injury. Participants will be randomly allocated by chance (like tossing a coin) to have treatment consisting of either a) Rehabilitation (and later surgery only if needed), b) surgery [ACL Reconstruction]. Patients will have been injured at least 4 months before with rupture shown by clinical assessment and/or a special scan (MRI). Questionnaires will assess the benefits of each treatment 18 months later. We will also consider the costs of each strategy. Patients have been involved in designing this study and developing the research question and study objectives. The findings, when published, will likely change NHS practice. The study could show that prior physiotherapy is useful leading to fewer operations and potentially saving the NHS up to £21 million per year. Alternatively, significant savings would also be achieved by cutting out unnecessary physiotherapy should the study reveal that a rehabilitation strategy is ineffective in patients with longer-standing injury. Regardless of any savings, the study will allow patients to be provided with the best clinical care.

Research activity codes: 7.3 MANAGEMENT AND DECISION MAKING
Health categories: INJURIES AND ACCIDENTS;MUSCULOSKELETAL