Comparison of patient-reported and objective functional measures during the early rehabilitative phase in patients with primary versus revision ACL reconstruction

Objectives: Few studies have determined how individuals who undergo a second ACL reconstruction (ACLR) perform in terms of objective and patient-reported outcomes in the early rehabilitation period compared to individuals who undergo primary ACLR. This study investigated the difference in strength and functional outcomes 3-5 months postoperatively in revision ACLR patients compared to primary ACLR patients. Design: Cross-Sectional Retrospective Chart Review. Setting: Single university-based orthopaedic practice. Participants: 143 patients who underwent ACLR (121 primary, 22 revision) Main outcome measures: Isokinetic knee extension and flexion strength at 60 degrees/s and 180 degrees/s, the IKDC, KOOS, and ACL-RSI 4.2 +/- 0.7 months after ACLR. Results: After controlling for age, sex, graft source, and time since surgery, there were no significant group differences for ACL-RSI (p = 0.771), IKDC (p = 0.950), and KOOS subscale scores (p = 0.335-0.740). Similarly, there were no significant group differences in isokinetic knee extension peak torque at 60 degrees/s and 180 degrees/s (p = 0.155, p = 0.147) and knee flexion peak torque 60 degrees/s and 180 degrees/s (p = 0.279, p = 0.325). Group LSIs were comparable for isokinetic knee extension and knee flexion. Conclusion: Three to five months postoperatively, revision ACLR patients performed similarly in terms of thigh strength, limb symmetry, and patient-reported function compared to primary ACLR patients.