Central quadriceps tendon for anterior cruciate ligament reconstruction. Part I: Morphometric and biomechanical evaluation.

We examined the anatomic and biomechanical adequacy of the central quadriceps tendon as an alternative graft source for anterior cruciate ligament reconstruction. Morphometry was performed on 15 preserved and 6 fresh-frozen specimens. Biomechanical testing was performed on the six fresh-frozen specimens. We initially used a triple suture through the tendon construction, and then clamping directly on the tendon. Morphometry yielded the following measurements: length, 6.1 +/- 1.0 cm; width, 2.7 cm (range, 2.1 to 3.7); and thickness, 7 mm (range, 6.4 to 7.8). The thickness was 1.8 times that of the patellar tendon. Biomechanical testing showed that suture failure occurred at 692 +/- 181 N, and tendon failure occurred at 1075 +/- 449 N. The load to tendon failure was 1.36 times that of a comparable-width patellar tendon graft, although the difference was not statistically significant. The failure mode was primarily through partial or complete tendinous avulsion, with only one specimen failing at midsubstance. These findings show the central quadriceps graft is of sufficient size and strength to be used for anterior cruciate ligament reconstruction.