The CAM-P-OS study protocol: a prospective randomized multicenter trial evaluating an active controlled motion device in the rehabilitation of surgically treated, isolated ankle fractures of Weber types B and C.

Abstract

Background: Displaced ankle fractures classified as Weber types B and C are common across all age groups. The standard treatment involves open reduction and internal fixation, followed by a rehabilitation program that includes 6 weeks of partial weightbearing. During this period, both passive and active range-of-motion exercises are performed under the supervision of a physiotherapist. Recently, a new device has become available, allowing active controlled motion of the ankle joint at home on top of the normal rehabilitation protocol. The purpose of this controlled randomized trial was to evaluate the superiority of this device as a supplement in standard rehabilitation protocols after distal fibular fractures.

Methods: This prospective controlled multicenter trial will include a minimum of 58 patients who have undergone surgical treatment for isolated distal fibular fractures of Weber types B and C. These patients will be randomized into 2 groups: Group 1 will undergo a standardized rehabilitation protocol with active and passive physiotherapy under partial weightbearing for 6 weeks with the active controlled motion device at home on top. Group 2 will receive the same rehabilitation without the device. Three German hospitals with different levels of care and 6 rehabilitation centers are involved in this study. The estimated study duration of 12 months started in October 2024. The follow-up will last 6 months after the recruitment of the last patient. The following assessments are performed: baseline after surgery; after 6 weeks; at 3 and 6 months; and with check-in calls after 2 and 4 weeks. The evaluation of effectiveness is based on FAOS, NRS, and SF-36 scores; changes in employment during the study; return-to-work; return-to-sports; and time-to-unrestricted weightbearing.

Discussion: This trial aims to collect valid data to determine whether the use of an active controlled motion device as a supplement to a standardized physiotherapy protocol after surgical treatment of ankle fractures leads to significantly improved outcomes. After evaluation of the results by the German Joint Federal Committee, a final assessment is made to make this device part of a future treatment protocol in the aftercare of surgically treated distal fibular fractures of Weber types B and C.

Trial registration: The trial is registered in the International Clinical Trials Registry Platform of the World Health Organization with the Main-ID DRKS00034202 on July 22nd, 2024 ( https://trialsearch.who.int/Trial2.aspx ?TrialID=DRKS00034202).