M edial lumbricals
A dductor pollicis
F lexor digitorum profundus/Flexor digiti minimi
I nterossei
A bductor digiti minimi and opponens
Innervates all intrinsic muscles of the hand (EXCEPT 2: thenar muscles & first two lumbricals – supplied by median nerve)
Pronator teres is innervated by the median nerve. Palmaris brevis is innervated by the ulnar nerve
Ulnar nerve
Origin
Branches
- C8, T1
Supplies (no muscles in the upper arm)
- Flexor carpi ulnaris
- Flexor digitorum profundus
- Flexor digiti minimi
- Abductor digiti minimi
- Opponens digiti minimi
- Adductor pollicis
- Interossei muscle
- Third and fourth lumbricals
- Palmaris brevis
Path
- Posteromedial aspect of upper arm to flexor compartment of forearm, then along the ulnar. Passes beneath the flexor carpi ulnaris muscle, then superficially over the flexor retinaculum into the palm of the hand.
 | |
| Image sourced from Wikipedia | |
Branches
| Branch | Supplies |
|---|---|
| Muscular branch | Flexor carpi ulnaris Medial half of the flexor digitorum profundus |
| Palmar cutaneous branch (Arises near the middle of the forearm) | Skin on the medial part of the palm |
| Dorsal cutaneous branch | Dorsal surface of the medial part of the hand |
| Superficial branch | Cutaneous fibres to the anterior surfaces of the medial one and one-half digits |
| Deep branch | Hypothenar muscles All the interosseous muscles Third and fourth lumbricals Adductor pollicis Medial head of the flexor pollicis brevis |
Effects of injury
| Damage at the wrist |
|
| Damage at the elbow |
|
