Confidence to Return to Play After Anterior Cruciate Ligament Reconstruction Is Influenced by Quadriceps Strength Symmetry and Injury Mechanism.

Abstract

Although the restoration of quadriceps strength symmetry is a primary rehabilitation goal after anterior cruciate ligament reconstruction (ACLR), little is known about the potential relationship between quadriceps strength symmetry and psychological readiness to return to play (RTP). Quadriceps strength symmetry will be associated with psychological readiness to RTP after ACLR. Secondarily, injury mechanism will influence the association between quadriceps strength and psychological readiness to RTP. Retrospective cohort. Level 3 (cohort study). A total of 78 female patients completed strength testing and the Injury-Psychological Readiness to Return to Sport (I-PRRS) scale at an outpatient clinical facility as part of return to sport testing after ACLR. Linear regression analysis was used to assess the relationship between the I-PRRS and the independent variables of interest (quadriceps strength symmetry and injury mechanism). For all patients combined, a significant symmetry × mechanism interaction was found. When split by injury mechanism, a significant linear relationship was found between quadriceps strength symmetry and the I-PRRS score in patients who experienced a noncontact injury (n = 55; P = 0.01; R2 = 0.24). No such relationship was found for those who experienced a contact injury (n = 23; P = 0.97; R2 = 0.01). Greater quadriceps strength symmetry was associated with greater psychological readiness to RTP in female athletes after ACLR. This relationship, however, was present only in those who experienced a noncontact injury. Clinicians should consider both the physical and the psychological factors in assessing a patient's readiness to RTP. This may be particularly important for those who have experienced an ACL tear through a noncontact mechanism.