Change in meniscal strain with anterior cruciate ligament injury and afterreconstruction

Meniscal injury has been well documented in association with injury to the anterior cruciate ligament. The purpose of this study was to evaluate the e ffect of anterior cruciate ligament transection and reconstruction on menis cal strain. Four differential variable reluctance transducer strain gauges were placed in the medial and lateral menisci of nine cadaveric knees. Each specimen was mounted to a six-degree-of-freedom knee testing device. Testi ng was conducted with the knee fully extended and at 45 degrees and 90 degr ees of flexion, both with and without applied axial load. At each angle of flexion, an anterior and posterior tibial load was applied. Next, the anter ior cruciate ligament was transected and the testing sequence was repeated. Finally, the ligament was reconstructed using a central one-third patellar tendon graft and the testing sequence was repeated. The results demonstrat ed statistically significant increases in meniscal strain in ligament-trans ected knees compared with intact specimens. A reduction in meniscal strain to a level similar to that detected in the ligament-intact knees was observ ed after anterior cruciate ligament reconstruction, These results have impo rtant clinical implications regarding the potentially deleterious effect of the anterior cruciate ligament-deficient knee on meniscal strain and the p otential benefit of anterior cruciate ligament reconstruction.