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Harvesting of Peroneus Longus Tendon Autograft
Published on: September 2, 2025
Medial hamstring muscle activation patterns are affected 1-6 years after ACL reconstruction using hamstring autograft
Stefán Magni Arnason1, Bjartmar Birnir, Tómas Emil Guðmundsson
1Department of Physical Therapy, School of Health Sciences, University of Iceland, Saemundargata 2, 101, Reykjavik, Iceland.
Summary
Anterior cruciate ligament reconstruction (ACLR) using hamstring-gracilis (HG) autografts alters hamstring muscle activation. Post-surgery rehabilitation should target medial hamstring (MH) strengthening for improved outcomes.
Area of Science:
- Orthopedics
- Sports Medicine
- Biomechanics
Background:
- Anterior cruciate ligament reconstruction (ACLR) often uses semitendinosus and gracilis (HG) autografts.
- Morphological changes in hamstring muscles post-ACLR are known, but activation patterns require further study.
Purpose of the Study:
- To investigate hamstring muscle activation differences between athletes post-ACLR and healthy controls.
- To compare medial (MH) and lateral (LH) hamstring activation during specific exercises.
Main Methods:
- Surface electromyography (EMG) measured hamstring muscle activation in 18 ACLR athletes and 18 controls.
- Activation was recorded during Nordic Hamstring (NH) and TRX hamstring curl (TRX) exercises.
Main Results:
- Lateral hamstring (LH) activation showed significant interlimb differences during the TRX exercise but not the NH exercise.
- Medial hamstring (MH) activation displayed group and exercise-dependent differences between limbs post-ACLR.
- Control participants showed consistent limb preference, while ACLR participants exhibited varied MH activation patterns.
Conclusions:
- Athletes post-ACLR using HG autografts demonstrate altered hamstring muscle activation patterns.
- Post-operative rehabilitation should focus on targeted medial hamstring (MH) activation and strengthening.
