Inferior Outcomes after Subsequent Revision or Contralateral ACL Reconstruction: A Cross-Sectional Study

Outcomes after revision anterior cruciate ligament (ACL) reconstruction (ACLR) have been reported as inferior to those after primary reconstruction, but evidence comparing revision and contralateral ACLR in physical activity and patient-reported outcomes (PROs) during early rehabilitation remains limited.

To describe and compare rates of return to preinjury physical activity, muscle strength, and PROs between 12 and 24 months of rehabilitation in patients after primary, revision, and contralateral ACLR.

Cohort study; Level of evidence, 3.

Patients from a rehabilitation registry who underwent ACLR were included in this cross-sectional study. They were categorized into groups, defined as primary (n = 1317), revision (n = 111), or contralateral (n = 80) ACLR. Return to physical activity was assessed using the Tegner activity scale. Muscle function was measured via isokinetic strength testing. PROs were evaluated using different questionnaires. Outcomes were compared across groups at 12, 18, and 24 months. In addition, subgroup analysis was performed, dividing patients by sex.

At 24 months, a significantly greater proportion of patients in the primary ACLR group had returned to their preinjury physical activity level compared with both the revision and contralateral ACLR groups (43.9% vs 27.1% and 25.7%, respectively). Patients in the primary ACLR group scored higher on different questionnaires compared to the other groups at all follow-up time points. Sex-specific analysis showed significant differences among female patients in future knee self-efficacy and quality of life, favoring primary ACLR.

Revision and contralateral ACLR were associated with lower rates of return to preinjury physical activity levels and less favorable PROs between 12 and 24 months after reconstruction compared with primary ACLR. Differences in muscle strength were limited, and most statistically significant differences had small effect sizes, ranging from η² = 0.007 to 0.056 for continuous outcomes and ω = 0.122 for return to preinjury physical activity, suggesting that the clinical relevance of these findings should be interpreted cautiously.