Isolated gracilis tendon harvesting is not associated with loss of strength and maintains good functional outcome

Purpose The gracilis tendon is a commonly used autologous graft. Most information on knee function and outcomes after its harvest is related to both semitendinosus- and gracilis tendon harvest. Therefore this study analyzed the effect of isolated gracilis tendon harvest from healthy, uninjured knees on thigh muscle strength and patient reported outcome measures (PROMs). Methods Stabilization of the acromioclavicular joint because of chronic instability was performed with autologous gracilis tendon in 12 patients. After a mean of 44 +/- 25 months after surgery, isokinetic peak-torque measurements of specific functions of the gracilis muscle were performed: knee flexion in a sitting position (flexion angles 0-90 degrees) and in prone position (flexion angles > 70 degrees), internal tibial rotation and hip adduction. The contralateral limb was control. Knee specific PROMs were collected including IKDC-2000 subjective evaluation form, Lysholm score, the Marx Activity Rating Scale and SF-36 health survey. Results No significant side-to-side differences were found regarding torque measurements. Excellent results were shown regarding the PROMs, which even in terms of IKDC-2000 (97 vs. 82 points, p = 0.001) exceeded significantly the age- and gender matched reference-data. Conclusion Isolated gracilis tendon harvesting was not associated with loss of strength in knee flexion, internal tibial rotation and thigh adduction. Additionally, good functional outcome as well as excellent knee-specific subjective outcome was found.