Musculoskeletal Tissue Asymmetries Following Anterior Cruciate Ligament Reconstruction

OBJECTIVE: To compare musculoskeletal tissue asymmetries between those who had undergone anterior cruciate ligament reconstruction (ACLR) and nonsurgical controls, and to evaluate the influence of sex on asymmetries and perceptions of knee function in ACLR patients. DESIGN: Cross-sectional cohort analysis. METHODS: Individuals (female, n = 11; male, n = 11) with a history of ACLR and matched controls (female, n = 10; male, n = 9) completed dual-energy x-ray absorptiometry scans to measure lower-body bone mineral content (BMC), total body fat percent (Fat%), and lean mass (LM). Perceptions of knee function were captured via the International Knee Documentation Committee (IKDC) instrument and interlimb asymmetry indices (AI%) were calculated for each dual-energy x-ray absorptiometry outcome. Surgical groups and sexes were compared using independent t tests ( P<.05) and Cohen’s effect sizes ( d). Additionally, Pearson’s correlation coefficients evaluated the association between AI% and IKDC scores. RESULTS: The ACLR group showed greater lower-body asymmetries, specifically less BMC and LM and greater Fat% in the ACLR limb ( P≤.044, d = 0.63-0.87). ACLR group sex comparisons found that females had lower IKDC scores, greater asymmetries for BMC and LM ( P≤.027, d = 0.40-0.74), and these asymmetries were negatively correlated with IKDC scores (all r≥0.755, P≤.007) while males demonstrated no such correlations. CONCLUSIONS: Individuals with a history of ACLR had persistent musculoskeletal tissue asymmetries that favored the nonsurgical leg. The asymmetries were greater in female versus male patients and were associated with lower perceptions of knee function. Thus, musculoskeletal imaging may provide complementary information to the current standard of care during ACLR rehabilitation. JOSPT Open 2025;3(1):59-68. Epub 28 October 2024. doi:10.2519/josptopen.2024.1242