The ulnar n. is formed from spinal roots C8 and T1. It innervates the following muscles: Flexor carpi ulnaris, Flexor digitorum profundus, Palmaris brevis, Adductor pollicis, Flexor pollicis longus, Interossei, Abductor digiti minimi, Opponens digiti minimi, Flexor digiti minimi, Lumbricales 3 & 4, and the Interossei.