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Flashcards in The Arm & Forearm Deck (18):
0

How are the muscles of the anterior compartment of the forearm innervated?

Median nerve
Except flexor carpi ulnaris and the medial half of fdp are innervated by the ulnar nerve

1

Which muscles make up the superficial layer of the anterior forearm?

What actions do they perform?

Pronator teres - pronates the forearm
Flexor carpi radialis - flexion at the wrist and radial deviation
Palmaris longus - flexion at the wrist, tenses the palmar aponeurosis
Flexor carpi ulnaris - flexion at the wrist and ulnar deviation

2

Which muscles make up the intermediate layer?

What actions to they perform?

Flexor digitorum superficialis

Flexion of the medial for digits at the MCPJs and the proximal IPJs.
The muscle body of FDS splits in to four separate muscle bodies, each giving rise to a separate tendon

3

Which muscles make up the deep layer of the anterior forearm?

What actions do they perform?

Flexor digitorum profundus - flexion at the distal IPJ
Flexor pollicis longus - flexes the thumb
Pronator quadratus - probated the forearm

4

How is the flexor digitorum profundus innervated?

Lateral half - median nerve
Medial half - ulnar nerve

5

Why is supination a more powerful movement than pronation?

The muscles involved in supination (biceps brachii and supinator) are larger and hence stronger than the muscle involved in pronation (pronator teres and pronator quadratus)

6

Which muscles make up the superficial layer of muscles in the posterior compartment of the forearm?

What actions do they perform?

Brachioradialis - flexion at the elbow
Extensor carpi radialis longus - extension at the wrist, radial deviation
Extensor carpi radialis brevis
Extensor digitorum - extension at the MCPJs and IPJs
Extensor digiti minimi - extension of the fifth digit at the MCPJs and IPJs
Extensor carpi ulnaris - extension at the wrist and ulnar deviation

7

How are the muscles of the posterior compartment of the forearm innervated?

Radial nerve

8

Which muscles make up the deep layer of muscles in the posterior compartment of the forearm?

What actions do they perform?

Supinator - supinates the forearm
Abductor pollicis longus - abducts the thumb
Extensor pollicis brevis - extends the thumb
Extensor pollicis longus - extends the thumb
Extensor indicis - extends the second digit at the MCPJ and IPJs

9

What is meant by a Monteggia fracture dislocation?

Ulnar shaft fracture with dislocation of the radial head at the capitulum
Children FOOSH
ORIF

10

What is meant by a Galeazzi fracture dislocation?

Fracture of the distal 1/3 of radius with dislocation of the DRUJ - widening of the joint
Children FOOSH, ORIF

11

How can we assess the alignment of the elbow on an X-ray?

Radiocapitellar line
On a lateral view, draw a line through the neck of the radius to the capitulum

12

What are the articulation of the radioulnar joints?

What movements do they allow?

Proximal - head of radius with ulna
Distal - round head of ulna with radius

Pronation and supination due to articular disc

13

Which muscles make up the anterior compartment of the arm?

What actions to they perform?

Brachialis - flexion at the elbow in all positions
Biceps brachii - supination and then flexion at the elbow
Coracobrachialis - flexion at the shoulder

Innervated by the musculoskeletal nerve

14

What are the attachments of the biceps brachii?

Long head: supraglenoid tubercle
Short head: coracoid process
Tendon: tuberosity of the radius

15

Which muscles make up the posterior compartment of the arm?

What actions do they perform?

Triceps brachii - extension at the elbow and assists in stabilising the shoulder joint
Anconeus - stabilises the elbow joint and assists the triceps in extension

Innervated by the radial nerve

16

The cubital fossa is a triangular shaped area on the anterior surface of the elbow joint as a transition between arm and forearm.

What are the boundaries?

What are the contents?

Superior: imaginary epicondylar line
Lateral: medial border of brachioradialis
Medial: lateral border of pronator teres
Roof: skin and bicipital aponeurosis
Floor: brachialis and supinator

Lateral to medial: radial nerve, biceps tendon, brachial artery, median nerve

17

What happens in biceps rupture?

Traumatic in the young, tendinipathy in the elderly
Usually the long head
Popeye sign on examination
Flexion and supination still in tact due to other muscles
Hook sign positive