Elbow, Forearm and Wrist Flashcards

Question

What muscles are involved in the movement of the radio-ulnar joints?

Answer 1

SUPINATION: - supinator - biceps - EPL - ECRL PRONATION: - pronator quadratus - pronator teres - FCR - PL - brachioradialis * In the supine position, the pronator teres is stretched around the bone. It is attached to the lateral side of the shaft of the humerus. Pronator quadratus is stretched into its approximately quadrate shape. Supinator has contracted here, and has pulled the radius round so that the bones are parallel again. In the prone position, the pronator teres has contracted and has rotated the radius round, as has pronator quadratus.

Answer 2

Flexion: - FCR and FCU – important - Long flexors of thumb and fingers, (PL, APL) Extension: - ECRL, ECRB, ECU – important - Long extensors of the thumb and fingers Radial deviation (abduction): - APL - FCR - ECRL - ECRB Ulnar deviation (adduction): - ECU - FCU * If the flexor muscles work together, you’ll get straightforward flexion. ** If just one of them works, you’ll get slight deviation one way or the other. It is the combinations of activities that determine the movement. *** In order to get abduction or adduction, there is a flexor and an extensor working. Flexors work together to carry out flexion; extensors work together to carry ou

Answer 3

At the elbow, the brachial artery divides into the ulnar and radial arteries The ulnar artery branches almost immediately to give a common interosseous branch - common interosseous branch immediately branches to give anterior & posterior interosseous arteries The radial artery continues down the forearm to the wrist. The posterior interosseous artery pierces the upper part of the interosseous membrane to supply the posterior compartment. The anterior artery supplies deep structures. arteries go down to palmer arches (deep and superficial)

Answer 4

Superficial and deep systems - Cephalic vein (superficial) runs up lateral border of arm - Basilic vein (superficial) runs up the medial border of arm Basilic veins joins venae comitantes to form the axillary vein in the arm Cephalic vein joins axillary vein in the axilla Axillary vein becomes the subclavian vein at the level of the first rib Cephalic and Basilic veins arise from the dorsal venous arch of the hand Commonly connected at the cubital fossa by the median cubital vein (not always present or prominent) * Median cubital vein is commonly used in phlebotomy * When median cubital vein is absent, cephalic or basilic in the region are used to take blood ** There is the dorsal venous arch, giving the cephalic vein laterally and the basilic vein medially. The median cubital vein joins them. It is not always present, or when it’s present it may be a very small, weedy vein. When present, it is the vein of choice for routinely taking blood *** Deep drainage follows the arteries. Particularly in the more distal parts of the limb, veins accompanying the artery are often not a single vein (that’s why they’re called the venous comitantes). This is seen both anteriorly and posteriorly

Answer 5

Superficial and deep systems, running with veins Cubital lymph nodes drain the forearm (usually 3 or 4 lymph nodes, often on the medial side) Cubital lymph nodes are very important – if they are enlarged, this may indicate HIV status, they may also get inflamed is due to syphilis Axillary nodes are also draining nodes for the distal parts of the upper limb

Answer 6

C5, 6, 7 Supplies all the anterior compartment of the upper arm Sensory to the lateral forearm (as the lateral cutaneous nerve of the forearm – terminal branch

Answer 7

C6, 7, 8, T1 Courses through the anterior compartment of the arm (no significant branches) Lies anterior to the elbow, with the brachial artery (easily damaged) – found in cubital fossa * Main nerve to the muscles of the forearm The median nerve supplies LOADS of the flexors, but only HALF of the flexor digitorum profundus

Answer 8

C8, T1 Courses via the posterior compartment of the upper arm No significant branches in the upper arm Lies behind the medial epicondyle at the elbow (easily damaged) The main nerve of the hand

Answer 9

C5, 6, 7, 8, T1 Supplies all the muscles of the posterior compartments of the upper arm and forearm Passes around the body of the humerus at its mid-shaft in the radial groove (easily damaged) Supplies triceps in the arm Courses via the anterior compartment of the upper arm more distally Divides just above the level of the elbow into: - Deep branch – the posterior interosseous nerve (motor – mainly extensor muscles) - Superficial branch – the superficial radial nerve (sensory)

Answer 10

As we get towards the hand, we see a retinaculum. It is the flexor retinaculum of the wrist (also the transverse carpal ligament) It is a structure that forms the roof of the carpal tunnel. The carpal tunnel allows lots of tendons and the median nerve to pass through to the hand This arrangement can be problematic