Abstract
Background: The muscle elasticity of vastus medialis (VM) during quadriceps setting (QS) decreases after anterior cruciate ligament reconstruction (ACLR). However, the recovery process of VM muscle elasticity during QS is unknown. In addition, it is unknown what the factor contributing to the VM muscle elasticity during QS at 4 weeks after surgery.
Objective: The purpose of this study was to investigate the chronological changes in VM muscle elasticity during QS before and immediately after ACLR and its relationship, using shear wave elastography (SWE).
Methods: In 19 knees of 19 patients who underwent ACLR, the muscle elasticity of the VM during QS was measured using SWE on both the unaffected side and the affected side a three time points: before surgery and at 2 days and 4 weeks after surgery. Multiple comparison and multiple regression analyses were performed.
Results: VM muscle elasticity during QS of the affected side was lowest at 2 days after surgery. In addition, VM muscle elasticity during QS at 2 days after surgery on the affected side was selected as an independent variable associated with VM muscle elasticity during QS at 4 weeks after surgery on the affected side.
Conclusion: These results suggest that VM muscle elasticity during QS at 2 days after surgery may be useful for predicting VM muscle elasticity during QS at 4 weeks after surgery following ACLR.
