NerveSpinal nerve

Intercostal nerve 3

Latin: Nervus intercostalis III sinistra

Paired structure: one on the left and one on the right side of the body.

View the intercostal nerve 3 in 3D

Roots

T3 anterior ramus.

Course

Runs in the costal groove of the third rib between the internal intercostal and innermost layer, with the vein above and artery below (VAN), passing forward in the neurovascular plane to the sternum.

Motor supply

Intercostal muscles of the third space.

Sensory supply

The T3 dermatome — the chest wall's third band, anterior and posterior.

Clinical relevance

The intercostal block's target plane; shingles of T3 band-blisters the chest wall's third strip, and post-herpetic neuralgia can persist for months or years.

Educational anatomy reference, not medical advice. About this content.