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

This study included 527 patients (178 female and 349 male) with unilateral anterior cruciate ligament (ACL) rupture who underwent arthroscopic ACL rec onstruction using bone-patellar tendon-bone autograft and interference scre w fixation. The follow-up examination was performed by independent observer s 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 subs core was 22 (0-25) points and the. Lysholm pain subscore was 19 (0-25) poin ts. 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) evaluatio n 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 we re recorded between the IKDC evaluation system and the Lysholm score (rho = 0.66), the patients' subjective evaluation (rho = 0.53), the Tegner activi ty level (rho = 0.34), all the laxity tests (rho greater than or equal to 0 .34) and the one-leg-hop test (rho = 0.28). The resumption of sporting acti vities and work as evaluated by the Tegner activity level correlated with t he patients' subjective evaluation (rho = 0.34) but did not correlate with the laxity tests, i.e., the manual Lachman test (rho = -0.06) and the total and anterior KT-1000 tests (rho = -0.06). Furthermore, none of the laxity tests correlated with the functional tests or the patients' subjective eval uation. We conclude that the IKDC evaluation system is a reliable and usefu l tool for evaluating the post-operative outcome after an ACL reconstructio n.