OVERVIEW
- The elbow serves to position the hand in space.
- The muscles acting here are often denervated in brachial plexus and proximal peripheral nerve injury patterns.
- With dysfunction at the elbow, the upper extremity cannot be properly positioned in space to perform normal functions even if normal hand or other distal function is preserved.
- Restoration of elbow movement must be a priority in peripheral nerve injury patients.
Structures of the Elbow
- Bones:
- Humerus
- Radius
- Ulna
- The elbow joint is a hinge joint.
Movements of the Elbow
- Flexion and extension are movements about a coronal axis.
Muscles of the Elbow (with detailed examination links)
| Muscle Name | Innervation | Basic Action |
|---|---|---|
| Biceps brachii | Musculocutaneous nerve | Elbow flexion, forearm supination. |
| Brachialis | Musculocutaneous nerve | Elbow flexion. |
| Brachioradialis | Radial nerve | Can assist in elbow flexion (with forearm in neutral position). |
| Triceps brachii | Radial nerve | Elbow extension. |
| Anconeus | Radial nerve | Elbow extension. |
| Extensor carpi radialis longus | Radial nerve | Extends the wrist (weak assistance in elbow flexion). |
| Pronator teres | Median nerve | Pronates the forearm (weak assistance in elbow flexion). |
Italics — Muscles that assist or may assist but are not the primary action of elbow joint flexion and extension. These include muscles that cross the elbow joint.