Arm and Forearm Flashcards
Describe some features of the arm
4 muscles
2 fascial compartments
3 large nerves
LARGE MEDIAL neurovascular bundle
State the muscles in the anterior arm
Biceps brachii
Coracobrachialis
Brachialis
Describe a feature of the biceps brachii
2 heads - Long head + Short head
Where do the heads of the biceps brachii attach ?
Short head attaches to the coracoid process of the scapula
Long head attaches to the supraglenoid tubercle of the scapula
Where do the heads of the biceps brachii insert ?
The 2 heads insert into the forearm via 2 different things :
- Radial tuberosity
- Bicipital Aponeurosis
State the innervation of the biceps brachii muscle
Musculocutaneous nerve
C5,6,7 (MAINLY C6)
State the movement of the biceps brachii
Supination - then flexion (synergist in elbow flexion)
Short head associated with stability
Describe features of the coracobrachialis
Goes from the coracoid process to the arm.
Runs alongside the short head of biceps
Where does the coracobrachialis attach ?
The coracoid process of the scapula
State the innervation of the coracobrachialis muscle
Musculocutaneous nerve
C5,6,7 (MAINLY C6)
State the movement of the coracobrachialis muscle
Flexion, adduction at GH joint
Associated with stability
State the movement of the brachialis muscle
Prime mover in elbow flexion.
State the attachment of the brachialis muscle
The anterior surface of the humerus
State the insertion of the brachialis muscle
The coronoid process of the ulna
State the innervation of the brachialis muscle
Musculocutaneous nerve
C5,6
What does the musculocutaneous nerve become in the forearm ?
It becomes the lateral cutaneous nerve of the forearm.
What is the biceps reflex ?
Deep tendon reflex
Afferents from muscle spindles
Efferent alpha motor neurons
Function of the biceps reflex test
Tests C5 and C6 spinal segments
Elicits a flexion jerk
State the muscle(s) in the posterior arm
Triceps brachii (has 3 heads)
- Long head
- Lateral head
- Medial head
Where do the heads of the triceps brachii insert ?
All 3 heads come together and insert onto the olecranon process of the ulna.
State the innervation of the triceps brachii
The radial nerve
C6,7,8 (MAINLY C7 and 8)
Describe the movements associated with the triceps brachii
Extensor of the elbow
Long head - shoulder extension (associated with stability)
What nerve supplies the anterior arm compartment ?
Musculocutaneous nerve
What nerve supplies the posterior arm compartment ?
Radial nerve
What happens due to damage of the radial nerve ?
Paralysis in the muscles of the posterior forearm.
- Wrist drop (floppy wrist)
Function of the triceps reflex test
Tests C6 and C7 (C8) spinal segments
Elicit an extension jerk
State features of the cubital fossa
Area anterior to the elbow
Borders
Roof
Floor
Contents
State the borders of the cubital fossa
Pronator teres
Brachioradialis
Line between the lateral and medial epicondyles
(this forms a triangle called the cubital fossa)
State the roof of the cubital fossa
Bicipital aponeurosis