Comparison of Remnant Preserved versus Conventional Anterior Cruciate Ligament Reconstruction

Abstract

PURPOSE: Surgical reconstruction of the anterior cruciate ligament (ACL) may reduces knee instability. It has been suggested that the lack of full recovery of knee function following ACL reconstruction is partially the result of a sensory deficit. The remnant preserving technique was developed to preserve the prorioception and to enhance the revasularzation of the reconstructed ACL. Therefore, the purpose of this study was to analyze the clinical results of comparing the remnant preserving technique with the conventional ACL reconstruction. METHODS: We have tested 40 patients ACL reconstruction by auto graft-hamstring tendon, by dividing the subjects into 2 different groups; Trial group (preservation of remnant, Group 1) and control group (no remnant, Group 2). We measured concentric peak torque measurements of the knee extensors and flexors at 60°/sec and 180°/sec on an Isokinetic dynamometry. Proprioceptive functions has been assessed using Joint position sense (JPS) and threshold to detection of passive motion (TDPM). Dynamic postural stability was measured as a stability index in the anterior-posterior and medial-lateral planes with the Biodex Stability System. All tests were measured postoperative 1year. For statistical analysis, we used an independent-sample t test and Pearson correlation and found the results to be statistically significant at p<.05. RESULTS: A significant difference was detected in proprioception. we found significant difference between the group 1 and group 2 for Joint position sense (1.79±0.63° vs 3.14±0.95°. p=0.012) and threshold to detect passive motion (1.73±0.68° vs 2.73±1.15°. p=0.007). In dynamic postural stability test, group 1 showed a significantly improved instability of 10.7±8.5% whereas group 2 resulted that of 17.5±8.8%(p=0.037). But, we found no significant difference between the groups for the test results of knee strength. CONCLUSIONS: We thought that the presence of the proprioceptive nerve fibers in the remnant of the ACL may provide a source for the reinnervation of the graft and restoration of normal proprioception. Therefore, preservation of the remnant ACL reconstruction is helpful in preserving the proprioception and function to stabilize the knee.