Can the gracilis be used to replace the anterior cruciate ligament in the knee? A cadaver study

Purpose: The purpose of this study was to evaluate whether a four-strand gracilis-only graft can be used in anterior cruciate ligament (ACL) reconstruction.

Study design: Cadaver study.

Methods: This study involved 16 cadaver knees. The length and diameter of the native ACL were measured in each one. The same measurements were performed on a four-strand graft of the gracilis only, the semitendinosus only and both tendons. Student's t-test was used to compare the various conditions.

Results: The average diameter of the G4 construct was 0.07 mm greater (1%) than the native ACL (p=0.044). The average cross-sectional area of the G4 construct was 1.2 mm(2) greater (3.9%) than the native ACL (p=0.049). The G4 was on average 38.9 mm longer than the intra-articular portion of the ACL (p<0.001).

Conclusion: A four-strand gracilis construct meets the anatomical specifications for use as an ACL reconstruction graft. By using the gracilis only, the morbidity associated with harvesting the gracilis and semitendinosus tendons should be reduced. Further studies must be performed to compare the biomechanical properties of this graft with other graft types and also to evaluate how this four-strand gracilis graft behaves in a clinical setting.