Adolescent Females With Concomitant Anterior Cruciate Ligament (Acl) and Meniscus Injury Have a Worse Jump Landing Strategy After Return to Activity Clearance Than Those With Isolated Acl Reconstruction

Meniscus injuries often accompany ACL tears, and can lead to many future concerns including an earlier onset of knee osteoarthritis. Meniscus injuries can impact joint load absorption, potentially leading to different landing strategies. In the adult population it has been shown that ten months after surgery there are no differences in jump performance between patients with concomitant meniscus and ACL injury and isolated ACL injury. However, the impact of concomitant injury on landing strategies and whether it is replicated in adolescent patients is still unclear. Considering that young females are among the highest risk for poor landing mechanics and associated ACL injury, we aimed to identify if jump outcomes differ between female patients who had a concomitant meniscus injury versus an isolated ACL injury after they were cleared post-operatively to return to activity (RTA). We conducted a cross-sectional analysis of 30 female adolescent patients who underwent to ACL reconstruction surgery (ACLR). Patients were classified as a concomitant group (meniscus and ACL injury) or an isolated group (only ACL injury). All participants were released by the attending surgeon to return to activity, and performed five trials of countermovement jump on two force plates (Bertec Corp., USA, 1000 Hz). The outcomes measured were the peak of ground reaction force (GRFp) and impulse during the propulsion phase, GRFp and absorption rate (GRFp/time to peak) during the landing phase, and jump height. Data were normalized to the participant's body weight or height. Mann-Whitney U, Independent t-tests, or chi-square tests were used to compare groups for demographic characteristics. A MANOVA was used to identify the difference between groups (isolated vs. concomitant injury). Seventy-seven percent of the patients presented a concomitant meniscus and ACL injury. There was no difference between groups for demographic characteristics, autograft type, or time since surgery (Table 1). The concomitant injury group presented lower GRFp and higher time to GRFp in the injured leg than the isolated injury group (Figure 1A-B). The absorption rate was lower in both legs for the concomitant injury group (Figure 1C-D). Female adolescent patients with a concomitant meniscus and ACL injury present a worse strategy in jump landing than those with isolated ACL injury 9 months post-ACLR. Concomitant meniscus and ACL injury lead to longer landing compensations, which suggests a protective mechanism in favour of the injured leg after ACLR. Therefore, the rehabilitation process and RTA clearance may take longer and require special attention to the landing strategy for those patients who have had surgery for concomitant injury. For any figures or tables, please contact the authors directly.