NerveSpinal nerve
Intercostal nerve 9
Nervus intercostalis IX sinistra
- Paired structure: one on the left and one on the right side of the body.
Roots
T9 anterior ramus.
Course
Ninth space's groove toward the umbilicus's band.
Motor supply
Ninth intercostals and abdominal wall slips.
Sensory supply
T9 dermatome — above the umbilicus.
Clinical relevance
Abdominal wall pain of intercostal origin (thoracolumbar, anterior cutaneous entrapment) mimics visceral disease — Carnett's sign (pain on tensing the wall) separates it.
Educational anatomy reference, not medical advice. About this content.