abdominal segment muscle

An abdominal segment muscle (known in anatomical terminology as abdominal segment of trunk muscle organ) is any muscle organ that is part of the abdominal segment of the trunk. This category includes the muscles of the anterior and lateral abdominal wall, as well as the posterior abdominal muscles associated with the lumbar spine.

These muscles surround the abdominal cavity, forming the anterior wall (rectus abdominis), the lateral wall (external oblique, internal oblique, transversus abdominis), and the posterior wall (quadratus lumborum, psoas major). They attach to the ribs, lumbar vertebrae, iliac crest, and pelvis.

Abdominal segment muscles protect and compress the abdominal contents, stabilize the lumbar spine, produce trunk movement (flexion, extension, lateral bending, rotation), and assist with breathing and other activities that require regulation of intra-abdominal pressure.

Muscle strains, hernias, diastasis recti, and chronic low back pain are common conditions associated with abdominal segment muscles. Weakness or dysfunction in these muscles is a major contributor to spinal instability and postural problems.

Key groups include the anterior abdominal muscles (rectus abdominis and pyramidalis), the lateral muscles (external oblique, internal oblique, transversus abdominis), and the posterior muscles (quadratus lumborum and the lumbar portions of the erector spinae and psoas).