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Author Spotlight: Implementing the Enhanced Recovery After Surgery Concept in Rehabilitation Following Anterior Cruciate Ligament Reconstruction
Published on: March 1, 2024
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Relationship between pre- and post-operative isokinetic strength after ACL reconstruction using hamstring autograft
J Riesterer1, M Mauch1, J Paul1
1Rennbahnklinik, Muttenz, Basel, Switzerland.
BMC Sports Science, Medicine & Rehabilitation
|December 9, 2020
Summary
Preoperative thigh muscle strength significantly impacts recovery after anterior cruciate ligament reconstruction (ACLR). Stronger preoperative quadriceps and hamstring muscles correlate with better outcomes, highlighting the need for pre-surgery strengthening programs.
Area of Science:
- Orthopedic Surgery
- Sports Medicine
- Rehabilitation Science
Background:
- Anterior cruciate ligament (ACL) ruptures are common in athletes, necessitating effective rehabilitation for return to sports (RTS).
- Persistent thigh muscle weakness post-ACL reconstruction (ACLR) can impede RTS and increase secondary injury risk.
- Understanding the role of preoperative muscle strength is crucial for optimizing patient outcomes.
Purpose of the Study:
- To compare thigh muscle strength before and after ACL reconstruction (ACLR).
- To investigate the correlation between preoperative and postoperative muscle strength.
- To emphasize the importance of preoperative muscle status and patient coaching.
Main Methods:
- Retrospective analysis of 80 patients undergoing primary, isolated ACLR with hamstring autografts.
- Bilateral isokinetic concentric strength measurements (60°/s) performed preoperatively and six months postoperatively.
- Primary outcomes included maximal knee extension/flexion torque, hamstrings-to-quadriceps (H/Q) ratio, and limb symmetry indices (LSI).
Main Results:
- Significant increases in maximal knee extension and flexion torque were observed in both operated and unaffected legs post-rehabilitation.
- The hamstrings-to-quadriceps (H/Q) ratio remained statistically unchanged.
- Limb symmetry index (LSI) for knee extension strength improved significantly, while flexion strength LSI showed no significant change. Strong positive correlations were found between pre- and post-operative strength for both knee extension and flexion.
Conclusions:
- Preoperative knee extension and flexion strength are strong predictors of postoperative strength performance after ACLR.
- Preoperative deficits in quadriceps and hamstring strength negatively impact functional outcomes following ACLR.
- Intensive preoperative screening and targeted strengthening are essential for maximizing leg strength before ACLR to improve recovery.
