Inner oblique abdominal muscle

Inner oblique abdominal muscle , vol. Obliquus Intemus Abdominis , - a wide flat muscle, is located inward from the external oblique abdominal muscle, in the anterolateral section of the abdominal wall. It starts from the outer 2/3 of the inguinal ligament, the intermediate line of the iliac crest and from the fasciae thoracolumbalis (at the junction of two fascia leaves).

The bundles of the internal oblique muscle fan out in a fanlike manner, mainly in an oblique direction from below and from behind, upward and anteriorly; The lower tufts go almost horizontally and obliquely down and forward. From them, thin beams descending along the course of the spermatic cord are separated; They are part of the. Mice, raising the testicle, from. Cremaster . The posterior fasciculi of the internal oblique muscle have an almost vertical direction and are attached to the outer surface of three or four lower ribs.

The remaining bundles, not reaching the lateral edge of the rectus abdominis, pass into the aponeurosis, which at the outer edge of this muscle is divided into 7 leaves going in front and behind this muscle, and participates in the formation of its vagina. In this case aponeurosis m. Oblique interni abdominis constitutes the upper 2/3 of the posterior wall of the vagina of the rectus abdominus, to a level whose border is an arcuate line, linea Arcuata . Having reached the median line, the fascicles of anterior and posterior leaves intertwine with bundles of the same name on the opposite side, participate in the formations of the white abdominal line (see "Vagina of the rectus abdominis").

Function: is the abdominal muscle; Cutting on one side, rotates the trunk in its direction.

Innervation: nn. Intercoslales (Th _vlll -Th _xll ), N. Iliohypogastrics (Th _xll -L _l ), n. Ilioinguinalis.

Blood supply: aa. Intercostales posteriores, epigastrica inferior, epigastrica superior, musculophrenica.