Anterior Cruciate Ligament Reconstruction with Hamstring Tendons Has no Deleterious Effect on Hip Extension Strength.

Background: Hamstring tendons are secondary hip extensors. Their harvest for graft in anterior cruciate ligament (ACL) reconstruction may create deleterious effect on hip extension strength. This is of particular importance in sports that need powerful hip extension force like climbing and sprinting. Due to scarcity of a comprehensive study in this area, we designed this prospective study to evaluate hip extension strength following ACL reconstruction using different types of grafts.

Methods: Fifty eight patients were enrolled in this prospective non-randomized case control study to compare isokinetic hip extension strength following ACL reconstruction with different graft types. Twenty patients in group A (both Semitendinosus and Gracilis tendons autograft (ST-G)), 14 patients in group B (Tibialis Posterior tendon allograft (Allograft)), 12 patients in group C (bone-patellar tendon-bone autograft (BPTB)) and 12 patients in group D (only semitendinosus autograft (ST)) were studied. Hip extension strength was tested post-operatively at three- and six-month periods using a Biodex isokinetic testing machine at a speed of 30 degree per second in operated (cases) and non-operated (controls) limbs.

Results: There was a significant increase in hip extension force between three and six month intervals in all four groups and in both operated (case) and non-operated (control) limbs ( P<0.05 , 95% CI). However, there was more increase in case limbs in comparison to control limbs. There was no significant difference in hip extension strength among all four groups (both in case and control limbs) in the third- and the sixth-month post-operative tests.

Conclusion: Graft type had no effect on hip extension strength following ACL reconstruction, and the harvest of one or both hamstrings had no deleterious effect on hip extension force.

Level of evidence: III.