Journal of biomechanics
-
Journal of biomechanics · Mar 2001
Architecture of the rectus abdominis, quadratus lumborum, and erector spinae.
Quantitative descriptions of muscle architecture are needed to characterize the force-generating capabilities of muscles. This study reports the architecture of three major trunk muscles: the rectus abdominis, quadratus lumborum, and three columns of the erector spinae (spinalis thoracis, longissimus thoracis and iliocostalis lumborum). Musculotendon lengths, muscle lengths, fascicle lengths, sarcomere lengths, pennation angles, and muscle masses were measured in five cadavers. ⋯ The proximal portion of the quadratus lumborum had a mean optimal fascicle length of 8.5 (1.5)cm and the distal segment of this muscle had a mean optimal fascicle length of 5.6 (0.9)cm. The physiologic cross-sectional area of the rectus abdominis was 2.6 (0.9)cm(2), the combined physiologic cross-sectional area of the erector spinae was 11.6 (1.8)cm(2), and the physiologic cross-sectional area of the quadratus lumborum was 2.8 (0.5)cm(2). These data provide the basis for estimation of the force-generating potential of these muscles.