Sex differences in rectus femorus morphology across different knee flexion positions.

Authors:  Myers H, Davis A, Lazicki R, Martinez C, Black D, Butler R

Quadriceps function is an important outcome following lower extremity injury and surgery. Measurements of quadriceps function are particularly helpful initially post-surgery, however traditional quadriceps strength measures like isokinetic testing are contraindicated during this time period. Inclusion of dynamic musculoskeletal ultrasound imaging in the clinical setting has been beneficial in understanding quadriceps activation specifically RF contraction (RF); however, there is a paucity of literature in this area. The purpose of the current study was to describe the cross sectional area (CSA) of the RF across varying knee flexion angles. The authors found that RF CSA is dependent on knee flexion angle in both males and females. As a result, the assessment of RF CSA should be conducted in a standardized position if this variable is to be utilized as a meaningful measure of muscle size during rehabilitation.

Abstract  |  Full Article (subscribers only)  |  Purchase Article