Graft force-setting technique in reconstruction of the anterior cruciate ligament

The objective of this work was to present a method for controlling the mechanical state of the knee during graft fixation in an ACL reconstruction; that is, adjusting the unloaded length of the graft at the time of fixation so that the force-carrying characteristics of the graft match that of the intact ACL, when the normal and recon structed knees are subjected to the same external load. To demonstrate the new method, an experimental knee testing system was used to measure ligament and graft forces with buckle transducers, as external loads were applied to five fresh knee specimens with a pneumatic load apparatus. ACL and collateral ligament force data were collected as anteriorly directed loads of 90 N (20 pounds) were applied at 0°, 30°, 60°, and 90° of flexion in the normal intact knee and the same knee following ACL excision. A composite graft was prepared, con sisting of distally based semitendinosus and gracilis autogenous tissue augmented with the Kennedy Liga ment Augmentation Device. Femoral fix...