Analysis of subjective, objective and functional examination tests after anterior cruciate ligament reconstruction A follow-up of 527 patients

Abstract

This study included 527 patients (178 female and 349 male) with unilateral anterior cruciate ligament (ACL) rupture who underwent arthroscopic ACL reconstruction using bone-patellar tendon-bone autograft and interference screw fixation. The follow-up examination was performed by independent observers at a median of 38 (21–68) months after the index operation. At the follow-up, the Lysholm score was 86 (14–100) points, the Lysholm instability subscore was 22 (0–25) points and the Lysholm pain subscore was 19 (0–25) points. The Tegner activity level was 6 (1–10). The one-leg-hop test was 91 (0–167)% of the non-injured knee. The difference in the anterior side-to-side laxity as measured with the KT-1000 arthrometer at 89 Newton (N) was 1.5 (–5–13) mm and the total KT-1000 side-to-side difference at 89 N was 2 (–7–11) mm. Using the International Knee Documentation Committee (IKDC) evaluation system, 177 (33.6%) patients were classified as normal (group A), 211 (40%) as nearly normal (group B), 109 (20.7%) as abnormal (group C) and 30 (5.7%) as severely abnormal (group D). The highest correlation coefficients were recorded between the IKDC evaluation system and the Lysholm score (ρ = 0.66), the patients’ subjective evaluation (ρ = 0.53), the Tegner activity level (ρ = 0.34), all the laxity tests (ρ≥ 0.34) and the one-leg-hop test (ρ = 0.28). The resumption of sporting activities and work as evaluated by the Tegner activity level correlated with the patients’ subjective evaluation (ρ = 0.34) but did not correlate with the laxity tests, i.e., the manual Lachman test (ρ = –0.06) and the total and anterior KT-1000 tests (ρ = –0.06). Furthermore, none of the laxity tests correlated with the functional tests or the patients’ subjective evaluation. We conclude that the IKDC evaluation system is a reliable and useful tool for evaluating the post-operative outcome after an ACL reconstruction.