Summary

The results showed the effectiveness and safety of simultaneous ACL and PCL reconstruction using ‘hybrid’ tendon autografts for combined ligamentous injuries. The most important finding of the present study was that there were no significant differences in the postoperative knee stability and clinical outcomes between that bicruciate reconstruction and bicruciate and collateral ligament reconstruc

Abstract

Introduction

Several procedures for combined rupture of both anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) in multiple knee ligament injuries have been reported. However, the clinical outcome of these treatments remains controversial. We have treated the multiple knee ligament injuries with combined ACL and PCL tears using ‘hybrid’ tendon autografts. Biomechanical studies have established that injuries to the posteromedial corner (PMC) or the posterolateral corner (PLC) of the knee worsen the deleterious effects of tears in both cruciate ligaments. We have proposed the following hypothesis: postoperative knee stability and clinical outcomes that underwent simultaneous ACL and PCL reconstruction may be significantly better from that underwent bicruciate and collateral ligament reconstructions. The purpose of this study was to test this hypothesis.

Methods

A retrospective study was conducted with forty-one patients (41 knees) who sustained unilateral multiple knee ligament injuries with both combined ACL and PCL tears. Five of 41 patients were surgically treated during the acute phase (< 3weeks after injury), and the remaining 36 patients were treated in the chronic phase (> 3weeks after injury). In the acute phase, the two-stage procedure was selected. First, we performed primary repair of the grade III PMC or PLC. Simultaneous ACL and PCL reconstruction were performed in the second stage. In the chronic phase, simultaneous ACL, PCL, and/or PMC or PLC reconstructions were performed. 15 knees required both simultaneous ACL and PCL reconstruction, and the others had the following additional ligament reconstruction; 14 knees required PMC reconstruction, and 8 knees required PLC reconstruction. Then, we divided into the two groups based on surgical procedures: In group I, 19 patients underwent only bicruciate reconstruction. In group II, 22 patients underwent bicruciate and PMC or PLC reconstructions. The patients were examined at more than 2 years after surgery. Statistical analyses were made using the paired t-test, the Mann-Whitney U test and the Chi square test. The significance level was set at p=0.05.
RESULT:
No patients showed a loss of knee extension more than 5°, while 4 patients in the group II revealed a loss of flexion more than 15°. The side-to-side difference in the total anteroposterior (A-P) translation measured at 20° and 70° of the knee flexion showed 1.9 ± 2.0 mm (group I: 1.9 ± 2.8 mm, group II: 2.0 ± 1.9 mm) and 2.5 ± 2.6 mm (group I: 1.8 ± 0.8 mm, group II: 2.7 ± 2.8 mm), respectively. A-P, varus and valgus stress radiographs showed no significant differences in comparison with that of the uninjured knee. The Lysholm score and Knee Injury and Osteoarthritis Outcome Score (KOOS) improved significantly (p<0.001) in both groups. In the International Knee Documentation Committee (IKDC) evaluation, 19 knees (group I: 10, group II: 9), 17 (group I: 9, group II: 8), and 5 (group II: 5) were graded as A, B, and C, respectively. There were no significant differences in the clinical results between the two groups. 3 patients who had acute intraarticular infections in the group II were treated by arthroscopic synovectomy within 2 weeks postoperatively and performed continuous irrigation treatment without the graft removal.

Discussion

The most important finding of the present study was that there were no significant differences in the postoperative knee stability and clinical outcomes between bicruciate reconstruction and bicruciate and collateral ligament reconstruction groups. The Lysholm overall clinical scores were favorable, and the postoperative knee stability was good without loss of knee extension more than 5°. But according to the IKDC rating, five patients were nearly abnormal. One important factor contributing to the unfavorable IKDC rating in some patientswas knee contracture that had already existed before surgery. This result indicated that the initial treatment and rehabilitation in the acute stage after injury are of importance for the following surgery.