Upper Limb 2 Station 4 - Posterior Arm and Radial Nerve

Question 1

What muscle takes up the entire posterior compartment of the arm?

Answer 1

Triceps brachii

Question 2

Triceps long head origin?

Answer 2

Infraglenoid tubercle of scapula

Question 3

Triceps lateral and medial head origins?

Answer 3

Lateral head – originates from the humerus, superior to the radial groove Medial head – originates from the humerus, inferior to the radial groove

Question 4

Triceps insertion?

Answer 4

All three converge into one tendon and insert into the olecranon process of the ulna bone

Question 5

Action of triceps?

Answer 5

Extension of elbow

Question 6

Innervation of triceps?

Answer 6

Radial nerve

Question 7

What does tapping on the triceps tendon test for?

Answer 7

Tests spinal segment C7

Question 8

What muscle is this and what is its action (green one) and whats its innervation?

Answer 8

Anconeus muscle

Extends and stabalises elbow joint

Radial nerve

Question 9

What cord does the raidal nerve arise from?

Answer 9

Posterior

Question 10

Does the radial nerve innervate all the extensor muscles of the elbow and wrist joint or just the elbow?

Answer 10

Yes it does wrists and elbow

Question 11

Brief path of the radial nerve?

Answer 11

Eneters arm anterior to the long head of triceps, goes deep and then curves round the middle of the hummerus in the raidal groove

Question 12

Seegmental root value of radial nerve and why?

Answer 12

C5 to T1 as posterior cord is made up of superior, middle and inferior trunks

Question 13

What branch of the brachial artery runs alongside the radial nerve when it goes deep?

Answer 13

Deep branch - profunda femoris artery

Question 14

What is the sign of a radial nerve injury?

Answer 14

Wrist drop