Ulna
Key info
- Ulna is medial of forearm.
- Longer bone out of the radius and ulna
- It has a shaft and two ends, of which the superior is the larger, presenting as a hooklike
projection for articulation with the trochlea of the humerus.
- The smaller rounded distal end is the head of the ulna, however it does not articulate
directly with the carpus. The ulna articulates laterally at each end with the radius.
Palpation
- @ proximal and posterior aspect of the elbow, olecranon oputline can be palpated and
identified; in Fl, it forms the ‘point’ of the elbow.
- Running downwards from this point, the posterior border can be palpated throughout its
length.
- At the lower end, the neck, head and styloid process can all be palpated with the styloid
process being the most posterior.
- When the forearm is fully pronated, the rounded head of the ulna is prominent on the back
of the wrist.
Radius
Key info
- Lies lateral to the ulna
- Shorter then ulna
- It articulates proximally with the capitulum of the humerus, distally with the scaphoid and
lunate of the proximal row of the carpus, and at each end with the ulna.
- It has a shaft and two ends, the inferior being the larger.
Palpation
- The radial head can be palpated within a ‘dimple’ on the posterolateral aspect of the elbow,
particularly when the elbow joint is extended as it overhangs the capitulum; it can be felt rotating
during pronation + supination.
- Shaft can be palpated on lateral distal end of forearm
Key info
- Ulna is medial of forearm.
- Longer bone out of the radius and ulna
- It has a shaft and two ends, of which the superior is the larger, presenting as a hooklike
projection for articulation with the trochlea of the humerus.
- The smaller rounded distal end is the head of the ulna, however it does not articulate
directly with the carpus. The ulna articulates laterally at each end with the radius.
Palpation
- @ proximal and posterior aspect of the elbow, olecranon oputline can be palpated and
identified; in Fl, it forms the ‘point’ of the elbow.
- Running downwards from this point, the posterior border can be palpated throughout its
length.
- At the lower end, the neck, head and styloid process can all be palpated with the styloid
process being the most posterior.
- When the forearm is fully pronated, the rounded head of the ulna is prominent on the back
of the wrist.
Radius
Key info
- Lies lateral to the ulna
- Shorter then ulna
- It articulates proximally with the capitulum of the humerus, distally with the scaphoid and
lunate of the proximal row of the carpus, and at each end with the ulna.
- It has a shaft and two ends, the inferior being the larger.
Palpation
- The radial head can be palpated within a ‘dimple’ on the posterolateral aspect of the elbow,
particularly when the elbow joint is extended as it overhangs the capitulum; it can be felt rotating
during pronation + supination.
- Shaft can be palpated on lateral distal end of forearm
