The rectus femoris tendon demonstrates comparable ultimate stress to the patellar tendon: A paired biomechanical...

The objective of this study was to compare the ultimate tissue strength of the rectus femoris (RF) and patellar tendons using paired soft-tissue grafts obtained from fresh organ donors, simulating clinical graft preparation.

Fourteen paired RF and patellar tendon (PT) grafts were harvested from seven organ donors and tested within 12 h postmortem. The RF was folded and mounted as a double-stranded graft to simulate its clinical use. All grafts underwent uniaxial tensile testing using a standardised protocol. Primary outcomes included ultimate stress (MPa), load to failure (N) and elongation at failure (%). Data distribution was assessed with the Shapiro-Wilk test, and paired t-tests or Wilcoxon signed-rank tests were applied accordingly. A post hoc power analysis was conducted to determine the minimum detectable difference in stress with the given sample size.

Ultimate stress did not differ significantly between RF and PT grafts (46.4 ± 10.5 MPa vs. 52.9 ± 9.7 MPa, p = 0.184). RF grafts showed significantly lower load to failure (885.9 ± 52.3 N vs. 1278.7 ± 207.5 N, p < 0.001) and greater elongation (1.2 ± 0.2% vs. 0.2 ± 0.1%, p < 0.001).

This study found that the double-stranded RF tendon exhibits ultimate tissue strength comparable to the patellar tendon, despite differences in load to failure and elongation. These results highlight the RF as a biomechanically viable graft option that merits further investigation. Given its consistent dimensions and soft-tissue-only harvest, the RF tendon represents a reproducible and potentially less invasive alternative for knee ligament reconstruction.

N/A.