RADIUS AND ULNA
Q.1 How will you determine the side to which the radius belongs?
- Upper end: Narrow and has a disc-shaped head
- Lower end: Wide, smooth anteriorly and ridges and grooves on the posterior aspect.
- Shaft: Convex laterally and concave forwards in the lower part. The medial border is sharp.
Q.2 Where the biceps brachii is inserted?
- Into rough posterior part of radial tuberosity.
Q.3 What structures are related to the posterior aspect of the lower end of the radius?
- The groove behind the medial part of lower end lodges tendons of extensor digitorum and extensor indicis.
- The oblique groove medial to dorsal tubercle lodges tendon of extensor pollicis longus.
- The groove lateral to dorsal tubercle lodges tendons of extensor carpi radialis longus and brevis.
- The lateral aspect is crossed by tendons of abductor pollicis longus and extensor pollicis brevis.
Q.4 How will you determine the side to which ulna belongs?
- The upper end is hook-like, with its concavity directed forwards.
- The lateral border of the shaft is sharp.
Q.5 Name the structures attached to the medial surface of the olecranon process.
- Origin of ulnar head of flexor carpi ulnaris.
- Posterior and oblique bands of ulnar collateral ligaments.
Lower part: Upper fibres of flexor digitorum profundus.
Q.6 Name the structures attached to the anterior surface of the coronoid process.
Whole of surface: Insertion to brachialis.
- Ulnar head of pronator teres,
- Ulnar head of flexor pollicis longus,
- Humeroulnar head of flexor digitorum superficialis,
- Anterior and oblique bands of ulnar collateral ligament.
Q.7 What are the flexor muscles in front of the forearm?
The flexor muscles in front of the forearm can be divided into three layers
- Deep layer – Flexor digitorum profundus – Flexor pallicis longus
- Intermediate layer – Flexor digitorum superficialis
- Superficial layer – Pronator teres – Flexor carpi radialis – Flexor carpi ulnaris
Q.8 Name the muscles arising from the aponeurosis of the posterior border of the shaft of the ulna.
- Flexor digitorum profundus,
- Flexor carpi ulnaris and
- Extensor carpi ulnaris.
Q.9 What are the muscles arising from the lateral part of the posterior surface?
From above downwards:
- Abductor pollicis longus
- Extensor pollicis longus
- Extensor indicis
Q.10 What is Colle’s fracture?
In adults, fall on the outstretched hand causes fracture of radius about one inch proximal to wrist joint and distal fragment is impacted dorsally and laterally.
Q.11 What is ‘Students’ elbow or ‘Miner’s elbow?
Inflammation of subcutaneous bursa present over olecranon due to repeated trauma. Commonly seen in miners and students.