Intratendinous Normal Saline Injection of Quadriceps and Patellar Tendon Allografts Does Not Reduce Mechanical Strength at Time Zero

Abstract

Purpose

To evaluate the tensile strength of human cadaveric quadriceps tendon (QT) and bone–patellar tendon–bone (BTB) allografts augmented by intratendinous saline injection.

Methods

Thirty-three QT and 14 BTB allografts harvested from fresh-frozen human cadaveric knees were tested using a servohydraulic test system. One half of all grafts were injected with 2 mL of intratendinous 0.9% saline, acting as a substitute for PRP, whereas the other half were soaked in saline as a control. Tensile testing was then performed and the ultimate load at failure (N) was measured. Statistical analysis, including descriptive, analysis of variance, and post hoc Tukey analysis, was performed. A P value less than .05 was considered significant.

Results

The mean ultimate load at failure was not significantly different for treated QT grafts and control QT grafts (330 ± 179 N vs 291 ± 195 N, P = .94). The mean ultimate load at failure was also not significantly different for treated BTB grafts and control BTB specimens (553 ± 195 N vs 656 ± 242 N, P = .76).

Conclusions

Intratendinous normal saline injection compared with passive normal saline exposure was not associated with any significant differences in ultimate load at failure for quadriceps and patellar tendon allografts at time zero.

Clinical Relevance

Graft rupture is a feared complication of anterior cruciate ligament reconstruction. The current study may provide surgeons with added confidence that intratendinous therapeutic injections of nonviscous substances do not significantly impair the tensile strength of QT and BTB allografts used in ACL reconstruction at time zero.