ACL SNNAP Trial: ACL Surgery Necessity in Non Acute Patients (ACL SNNAP)

Comparison of the Clinical and Cost Effectiveness of Two Management Strategies for Non-acute Anterior Cruciate Ligament (ACL) Injury: Rehabilitation Versus Surgical Reconstruction.

The primary objective of this study is to determine in patients with non-acute Anterior Cruciate Ligament Deficiency (ACLD) whether a strategy of non-surgical management [Rehabilitation] (with option for later ACL reconstruction, only if required) is more clinically effective and cost effective than a strategy of surgical management [Reconstruction].

The ACL SNNAP study is a pragmatic multi-centre randomised controlled trial with two-arm parallel groups and 1:1 allocation ratio to compare non-surgical management (Rehabilitation) and surgical management (Reconstruction) options for patients with a symptomatic non-acute ACL deficient knee. The objective is 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). Target sample size is 320 patients recruited from approx. 30 NHS orthopaedic units. An internal pilot will be conducted with clear progression criteria regarding recruitment. Both interventions are routine NHS treatments. Intervention content is based on a minimal set of pre-established criteria in order to ensure the integrity of the comparison while allowing for varying in practice in delivering the interventions between both surgeons and physiotherapists. This largely pragmatic approach will allow clinical management to reflect current practice and resource use within the NHS thus aiding generalisation. Other than the allocated intervention, both groups will be followed-up in the same way to exclude bias. Follow up for study purposes will be by patient self-reported questionnaire completed using an electronic data capture collection system (a postal option will also be available). The questionnaire will include the outcomes indicated in section 4 and will be completed by participants at baseline, 6, 12 and 18 months. Non-response will be minimised through use of multiple reminders such as web based, phone and text. Neither participants nor health care practitioners (surgeons and physiotherapists) can be blinded to receipt of the intervention.

Anterior Cruciate Ligament, ACL, Anterior Cruciate Ligament deficiency, ACL deficiency, ACLD, Anterior Cruciate Ligament reconstruction, ACL reconstruction, Anterior Cruciate Ligament physiotherapy, Anterior Cruciate Ligament rehabilitation, ACL physiotherapy, ACL rehabilitation, Anterior Cruciate Ligament management, ACL management

Non-surgical management [Rehabilitation] with option for later Anterior Cruciate Ligament (ACL) reconstruction, only if required.

Routine ACL rehabilitation protocols used at the participating site will be followed. As part of the site selection process, documentary evidence of the use of or willingness to adopt a rehabilitation protocol that reflects the guidelines of the mandatory aims/goals set for the study rehabilitation intervention will be required.

All surgical reconstructions will be patella tendon or hamstrings tendon depending on the surgeon's preference. All other care will be routine, including immediate post-operative care.

The score is derived from 4 of 5 subscales; pain, symptoms, difficulty in sports and recreational activities, knee related quality of life.

All 5 subscales of the KOOS will be included (the fifth scale being activities of daily living). Anterior Cruciate Ligament Quality of Life Score (ACL-QOL)

Activity level will be assessed using the Modified Tegner scale, graded from 1 (low activity levels) to 10 (professional level).

Any complications associated with undergoing ACL deficiency treatment will be recorded. This includes; for surgery group; re-admission, delayed hospital discharge, infection, unexpected poor range of movement (stiffness), excess bleeding, continued swelling, episodes of giving way, continued feeling of instability. For non-surgical group; continued swelling, episodes of giving way.

Generic quality of life (self-reported outcome measure covering 5 health domains and used to facilitate the calculation of Quality Adjusted Life Years in health economic evaluations).

Detailed resource use data on initial treatments received (surgical reconstruction or rehabilitation) and on subsequent healthcare contacts including re-operations (surgery arm), subsequent surgical reconstructions (rehabilitation arm), surgery-related complications, further rehabilitation, and primary care and other secondary care contacts out to 18 months post-randomisation. In addition, data will be collected on ability to work (e.g. sickness absences/return to work number of days off work and subjective working ability).

Inclusion Criteria: Participant is willing and able to give informed consent for participation in the study. Male or Female, aged 18 years or above. Symptomatic ACL deficiency of the native ligament1 (instability-episodes of frank giving way or feeling unstable) with ACL deficiency (either partial or complete tear) confirmed using clinical assessment and MRI scan. Exclusion Criteria: Acute phase of primary ACL injury i.e. not recovered from any acute symptoms relating to their initial ACL injury. Previous knee surgery (other than diagnostic arthroscopy or partial meniscectomy) to index knee concomitant severe injury to contra-lateral knee. Meniscal pathology with characteristics that indicate immediate surgery i.e. locked knee, large bucket handle or complex cartilage tear producing mechanical symptoms. Knee joint status of grade 3 or 4 on the Kellgren and Lawrence scale, Grade 3 MCL/LCL injury, associated PCL/PLC injury Inflammatory arthropathy. Pregnancy.

Beard DJ, Davies L, Cook JA, Stokes J, Leal J, Fletcher H, Abram S, Chegwin K, Greshon A, Jackson W, Bottomley N, Dodd M, Bourke H, Shirkey BA, Paez A, Lamb SE, Barker K, Phillips M, Brown M, Lythe V, Mirza B, Carr A, Monk P, Morgado Areia C, O'Leary S, Haddad F, Wilson C, Price A; ACL SNNAP Study Group. Rehabilitation versus surgical reconstruction for non-acute anterior cruciate ligament injury (ACL SNNAP): a pragmatic randomised controlled trial. Lancet. 2022 Aug 20;400(10352):605-615. doi: 10.1016/S0140-6736(22)01424-6.

Davies L, Cook J, Leal J, Areia CM, Shirkey B, Jackson W, Campbell H, Fletcher H, Carr A, Barker K, Lamb SE, Monk P, O'Leary S, Haddad F, Wilson C, Price A, Beard D. Comparison of the clinical and cost effectiveness of two management strategies (rehabilitation versus surgical reconstruction) for non-acute anterior cruciate ligament (ACL) injury: study protocol for the ACL SNNAP randomised controlled trial. Trials. 2020 May 14;21(1):405. doi: 10.1186/s13063-020-04298-y.