Which nerve arrangement correctly describes the innervation of the internal oblique muscle?

Which nerve arrangement correctly describes the innervation of the internal oblique muscle?

• A. Iliohypogastric nerve
• B. Ilioinguinal nerve
• C. Subcostal nerve
• D. Iliohypogastric nerve and ilioinguinal nerve

Answer: (D)

The internal oblique is innervated by nerves that supply the lower anterior abdominal wall, with two key contributors in this region: the iliohypogastric nerve and the ilioinguinal nerve. Both originate from the L1 ventral ramus and travel in the abdominal wall to give motor branches to the internal oblique (as well as to the transversus abdominis). Because each of these nerves provides direct motor input to this muscle, describing its innervation as coming from both iliohypogastric and ilioinguinal nerves best reflects the actual pattern of innervation in clinical anatomy. The subcostal nerve does contribute to the abdominal wall muscles in part, but the combination of iliohypogastric and ilioinguinal nerves more accurately represents the primary motor supply to the internal oblique.

The internal oblique is innervated by nerves that supply the lower anterior abdominal wall, with two key contributors in this region: the iliohypogastric nerve and the ilioinguinal nerve. Both originate from the L1 ventral ramus and travel in the abdominal wall to give motor branches to the internal oblique (as well as to the transversus abdominis). Because each of these nerves provides direct motor input to this muscle, describing its innervation as coming from both iliohypogastric and ilioinguinal nerves best reflects the actual pattern of innervation in clinical anatomy. The subcostal nerve does contribute to the abdominal wall muscles in part, but the combination of iliohypogastric and ilioinguinal nerves more accurately represents the primary motor supply to the internal oblique.