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Patellar and hamstring autografts are associated with different jump task loading asymmetries after ACL
Joshua J Miles1,2, Enda King1,3, Éanna Cian Falvey1,4
1Sports Medicine Research Department, Sports Surgery Clinic, Dublin, Ireland.
Scandinavian Journal of Medicine & Science in Sports
|April 30, 2019
Summary
Athletes undergoing anterior cruciate ligament reconstruction (ACLR) with bone-patellar-tendon-bone (BPTB) grafts show greater limb loading differences than those with hamstring tendon (HT) grafts 9 months post-surgery. These asymmetries may increase contralateral knee injury risk.
Area of Science:
- Orthopedics
- Sports Medicine
- Biomechanics
Background:
- Athletes with anterior cruciate ligament reconstruction (ACLR) face higher re-injury rates, particularly to the contralateral limb.
- Graft type, specifically bone-patellar-tendon-bone (BPTB) versus hamstring tendon (HT) autografts, may influence these re-injury rates due to altered biomechanics.
- Lower-limb loading asymmetries are suspected to play a role in the increased risk of contralateral injury post-ACLR.
Purpose of the Study:
- To compare countermovement jump (CMJ) phase-specific impulse asymmetries between athletes with BPTB and HT autografts 9 months post-ACLR.
- To determine the relationship between these impulse asymmetries and isokinetic strength asymmetries.
- To inform rehabilitation strategies by understanding graft-specific biomechanical differences.
Main Methods:
- Bilateral countermovement jumps (CMJs) were analyzed in male field sport athletes 9 months post-ACLR, divided into BPTB (n=22) and HT (n=22) autograft groups.
- An uninjured control group (n=22) was included for comparison.
- Phase-specific impulse asymmetries were calculated and compared between groups. Linear regression analyzed the association between impulse and isokinetic strength asymmetries.
Main Results:
- Athletes with BPTB autografts exhibited significantly greater impulse asymmetries during both the eccentric and concentric phases of the CMJ compared to HT autograft athletes.
- Isokinetic knee extensor strength asymmetry was a significant predictor of concentric impulse asymmetry in both BPTB and HT groups.
- No significant relationship was found between strength asymmetry and eccentric impulse asymmetry.
Conclusions:
- Bone-patellar-tendon-bone (BPTB) autografts are associated with greater lower-limb loading asymmetries 9 months after anterior cruciate ligament reconstruction (ACLR) compared to hamstring tendon (HT) autografts.
- These graft-specific loading asymmetries may contribute to the observed higher rates of contralateral anterior cruciate ligament (ACL) injuries in BPTB athletes.
- Rehabilitation programs should consider targeting these graft-specific loading asymmetries before athletes return to play (RTP).
Keywords:
IKDCbiomechanicscountermovement jumpground reaction forceimpulseisokinetic dynamometryphase-specificMore Related Videos
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