- See: Forearm Extensors:
- Anatomy:
- origin: common extensor tendon off lateral epicondyle;
- insertion: tendon of extensor digitorum at proximal phalanx of little finger & into dorsal expansion of finger extensor tendons;
- action:
- extends proximal phalanx of little finger at MP joint & assists wrist extension;
- extends the middle and distal phalanges especially when proximal phalanx is held in flexion;
- nerve supply: posterior interosseous branch of deep radial nerve (C6, C7, C8);
- synergists: extensor digitorum;
- Tunnel V:
- extensor digiti minimi lies over radioulnar articulation & may be the first tendon to be involved in RA;
- overlies the distal ends of the radioulnar articulation on the dorsum of wrist, contains extensor digitorum minimi;
- tunnel is palpable as slight indentation just lateral to the ulnar styloid process;
- to palpate extensor digiti minimi, have pt rest his palm upon table and raise the little finger;
- this tendon can move independently;
- extensor digiti minimi lies over radioulnar articulation & may become involved in RA of the joint;
- it may be subject to attrition, either from friction due to dorsal dislocation of the ulnar head or from synovitis
Extensor digiti minimi tendon transfer to prevent recurrent ulnar drift.