Summary

Partial-thickness quadriceps tendon grafts is significantly lower ultimate load and stiffness that other potential ACL grafts where as a full-thickness quadriceps tendon allografts with bone plugs were comparable to bone-patellar tendon-bone grafts and possessed the ultimate tensile force and stiffness needed to be a viable ACLR graft choice.

Abstract

Background

Despite increasing interest in utilizing quadriceps tendon grafts in anterior cruciate ligament reconstruction (ACLR), data on the optimal quadriceps graft thickness is limited. It is important that the grafts being utilized in this procedure have comparable biomechanical properties to the native anterior cruciate ligament (ACL).

Purpose

To characterize the mechanical properties for the quadriceps tendon, comparing full-thickness QT grafts with and without bone-plugs to a partial-thickness QT graft, and comparing the three QT grafts to 4-stranded ST (4-SST) and BTB grafts and one experimental graft, RF
Study Design: Controlled Laboratory Study

Methods

Forty-eight (N=48) young cadaveric grafts were utilized (mean age 32 ? 6 years), with N=8 specimens in each of the following groups; 1) full-thickness quadriceps tendon with bone, 2) full-thickness quadriceps tendon without bone, 3) partial-thickness quadriceps tendon without bone, 4) bone-patellar tendon-bone, 5) double rectus femoris, and 6) quadrupled semitendinosus tendon. Each specimen was harvested and rigidly fixed in custom clamps to a dynamic tensile testing machine for biomechanical evaluation. Graft ultimate load and stiffness were recorded. Independent groups one-factor ANOVAs and Tukey’s pairwise comparisons were performed for statistical analyses.

Results

Full-thickness quadriceps tendon with bone and semitendinosus tendon grafts demonstrated similar ultimate loads to bone-patellar tendon-bone grafts (p = 0.331 and p = 0.975, respectively). Furthermore, no significant differences were observed between the ultimate loads of full-thickness vs. partial-thickness quadriceps tendon grafts without bone (p = 0.460) or between full-thickness quadriceps grafts with vs. without bone (p = 0.613). However, full-thickness quadriceps tendon grafts with bone had significantly greater ultimate loads than partial-thickness quadriceps tendon grafts without bone (p = 0.0169).

Conclusions

Full thickness QT grafts with bone had similar material properties to BTB and a 4-SST, whereas this study suggests that partial thickness QT or QT grafts without bone should be used with considereation.