Thoracic limb muscle theory

Question 1

Thoracic limb is divided into muscles of:

Answer 1

Divides into:
- the shoulder joint
- the elbow joint
- the radioulnar joints
- the carpal joint
- the digits

Question 2

What are the intrinsic muscles of the thoracic limb responsible for?

Answer 2

The intrinsic muscles of the thoracic limb are responsible for the movements of the separate parts of the limb, together with the joints and ligaments

• major function is the extension and flexion of the joints

Question 3

Muscles of the shoulder joint, where do they originate and end, what do they do and how are they divided?

Answer 3

• take origin from the scapula and end on the humerus

They flex, extend or act as ligaments to brace certain hinge joints

Divided into:
Lateral shoulder muscles can be divided into
- supraspinatus
- infraspinatus
- deltoideus
- teres minor

Medial shoulder muscles are divided into
- teres major
- articularis humeri
- subscapularis
- coracobrachialis

Question 4

Muscles of the elbow joint where does it start, where does it bridge and how does it divide?

Answer 4

• Start from the scapula or humerus and bridge the shoulder and elbow joint or just the elbow joint.

Divides into:
- brachialis
- biceps brachii
- triceps brachii
- anconeus
- tensor fasciae antebrachii

Question 5

Muscles of the radiounar joints what are the differences between species and how does it divide?

Answer 5

• muscles that are well developed and functional only in carnivores. Vestigial or missing in other domestic animals due to reduced or lost capability for these movements.

Divides into:
Supinators of the forearm:
- brachioradialis
- supinator

pronators of the forearm
- pronator teres
- pronator quadratus

Question 6

Muscles of the carpal joint where do they start and end, what do they act as and how do they divide?

Answer 6

• cover the antebrachial skeleton, start around the elbow joint/humerus and end around the carpus/metacarpus
• mainly act as flexors or extenders

Divided into:
- extensor carpi radialis
- extensor carpi ulnaris
- flexor carpi radialis
- flexor carpi ulnaris

Question 7

Muscles of the digits where do they start and go and how do they divide?

Answer 7

• cover the antebrachial skeleton and span several joints, start around the elbow joint from the humerus and run along the carpus to the different parts of the digits

Divide into:
- extensor digitorum communis
- extensor digitorum lateralis
- abductor pollicis longus
- extensor digiti 1 et 2

Question 8

Short digital muscles how do they differ in species and how are they divided?

Answer 8

• different in species based on number, structure and function

Divided into:
- mm. interossei
- mm. lumbricales
- flexor digitorum brevis