University:
Western Sydney University
Course:
MEDI 2003 | Clinical Sciences 2
Academic year:

2024
Views:

268

Pages:

4
Author:

Mariam A. A.

Nerve supply of the Abdomen Nerves Origin Thoracoabdominal (T7T11) Continuation of lower (7th–11th) intercostal nerves distal to costal margin T7-T9 Subcostal (anterior ramus of T12) Course Run between second and third layers of abdominal muscles; branches enter subcutaneous tissue as lateral cutaneous branches of T10–T11 (in anterior axillary line) and anterior cutaneous branches of T7–T11 (parasternal line) 7th–9th intercostal Anterior divisions continue across nerves (anterior rami costal margin in subcutaneous of spinal nerves T7– tissue T9) Spinal nerve T12 Runs along inferior border of 12th rib; then passes onto subumbilical abdominal wall between second and third layers of abdominal muscles Iliohypogastric (L1) As superior terminal branch of anterior ramus of spinal nerve L1 Ilio-inguinal (L1) As inferior terminal branch of anterior ramus of spinal nerve L1 Distribution muscles of anterolateral abdominal wall and overlying skin kin of right and hypochondriac regions left Muscles of anterolateral abdominal wall (including most inferior slip of external oblique) and overlying skin, superior to iliac crest and inferior to umbilicus Skin overlying iliac crest, upper inguinal, and hypogastric regions; internal oblique and transversus abdominis muscles Pierces transversus abdominis muscle to course between second and third layers of abdominal muscles; branches pierce external oblique aponeuroses of most inferior abdominal wall Passes between second and third Skin of lower inguinal region, layers of abdominal muscles; then mons pubis, anterior scrotum traverses inguinal canal or labium majus, and adjacent medial thigh; inferior most internal oblique and transversus abdominis Neurovascular plane • Thoraco-abdominal nerves - Distal abdominal parts of the anterior rami of the inferior 6 thoracic nerves (T7-T11) - They are former inferior intercostal nerves distal to the costal margin • The lateral cutaneous branches pierce aponeurosis -> travel behind rectus abdominus muscle then pierce rectus sheath to end in anterior cutaneous branches