The abdominal wall is constructed from a discontinuous skeletal framework (xiphoid process, costal margin, 11th and 12th ribs, lumbar vertebrae L1–L5 with intervertebral discs, iliac wings, and superior sacrum) bridged by muscular components that fill the gaps between skeletal landmarks. These muscles are organized into a posterior group (quadratus lumborum, psoas major, psoas minor, iliacus) and an anterolateral group, the latter subdivided into flat muscles (three paired layers, including the external abdominal oblique with its aponeurosis) and vertically oriented muscles (rectus abdominis, divided by tendinous intersections and bounded by the linea semilunaris and linea alba, plus the variably present pyramidalis). This is a topic in gross human anatomy concerned with regional musculoskeletal structure of the trunk.
The abdominal wall is constructed from a discontinuous skeletal framework (xiphoid process, costal margin, 11th and 12th ribs, lumbar vertebrae L1–L5 with intervertebral discs, iliac wings, and super…