Motor Imagery to Facilitate Sensorimotor Re-Learning (MOTIFS: More Learning) After Anterior Cruciate Ligament Injury: A Randomized Controlled Trial Protocol

Introduction: Treatment after Anterior Cruciate Ligament (ACL) injury includes physical therapist supervised neuromuscular training, with or without surgical reconstruction, aiming to improve patient-reported outcomes and muscle function. Despite this treatment, sensorimotor deficiencies persist, possibly constituting a contributing factor for risk of re-injury, early-onset osteoarthritis, and a lower rate of return to sport. Central nervous system (CNS) reorganization may be an underlying mechanism for the sensorimotor deficiency. Integrating a form of mental training, Dynamic Motor Imagery (DMI), into neuromuscular training represents an appealing approach to including the CNS in rehabilitation. We hypothesize that 12 weeks of our novel training method, called MOTor Imagery to Facilitate Sensorimotor relearning (MOTIFS), will improve muscle function and patient-reported outcomes to a greater extent than current neuromuscular training.
Methods: This is a protocol for a 1:1 single assessor-blinded adaptive cluster-randomized controlled trial. Eighty-eight athletes in soccer, handball, basketball, and floorball with ACL injury with a goal of returning to sport, and who are currently undergoing physical-therapist supervised rehabilitation including single-leg hop training will undergo a 12-week intervention. Physical therapy clinics in Skåne County, Sweden will be randomized to administer either the MOTIFS training or care-as-usual. The MOTIFS model was developed by the authors in order to integrate Dynamic Motor Imagery (DMI) into neuromuscular training. The primary outcomes will be between-groups change from baseline to 12 weeks in relative within-subjects change in hop performance on the injured leg in a side-hop task and the ACL Return to Sport after Injury Scale (ACL-RSI). Secondary outcomes include evaluating muscle function with a hop test battery and assessment of postural orientation errors, as well as patient-reported outcomes such as knee-related quality of life, physical activity enjoyment, and perceived stress. At 12-month follow-up, patient-reported outcomes will once again be assessed. A sub-group will undergo phenomenological interviews upon completion of the intervention to gain further insight into the patient’s experience of the rehabilitation process.
Ethics and Dissemination: Results will be published in a peer-reviewed journal, popular-science articles and at international conferences. The study was approved by the Regional Ethical Review Board in Lund, Sweden (Dnr 2016/413).
Study registered on ClinicalTrials.gov (Identifier: NCT03473821)