Revision anterior cruciate ligament reconstruction: Three- to nine-year follow-up

Purpose: With the increasing number of primary anterior cruciate ligament (ACL) reconstructions, revisions are more frequent. The literature quotes inferior results for revision cases when compared with primary ACL reconstruction. The purpose of the study was to review our institution's experience with revision ACL reconstruction. Type of study: Retrospective case series. Methods: Thirty-five revision cases were performed between 1993 and 1999. Twenty-nine were available for follow-up. Subjective scores were calculated for Lysholm, Tegner, and International Knee Documentation Committee (IKDC) forms. Objective IKDC scores were determined. KT-1000 measurements were performed as well as isokinetic strength testing of quadriceps and hamstrings. Plain film radiographs were obtained to assess degenerative changes. Results: The average patient age at time of revision was 30.2 years, the average time to revision was 56 months, the follow-up from last revision was 67 months. Twenty-two patients had bone-patellar tendon-bone (BPTB) allograft, 6 had contralateral BPTB autograft, and 1 patient had Achilles allograft. Overall, KT-1000 measurement showed an average of 2.78 mm side-to-side difference of displacement. The allograft versus the autograft group was 3.21 mm versus 1.33 mm, respectively. Prerevision data were unavailable. However, all patients had a positive pivot-shift test before revision. Average postrevision Lysholm, Tegner, and subjective IKDC scores were 86.6, 11.86, and 85.86, respectively. Concerning the IKDC objective scores, 15 patients had an A score, 8 had a B score, and 4 had a C score. All 29 patients available for follow-up reported that they would have the surgery again. The average strength of quadriceps and hamstrings ranged from 82% to 88% of uninvolved side. Conclusions: This study provides long-term follow-up with good results for revision ACL reconstruction. Attention to principles when performing revision ACL surgery is critical to provide satisfactory results. Level of evidence: Level IV.