EXAM 2: Forearm

Question 1

The ulna attaches to the ______

The radius attaches to the ______

How is force transferred between the radius and the ulna? (through what structure)

Answer 1

The ulna attaches to the humerus (reminder the brachialis is attached to the ulna tuberosity)

The radius is attached to the wrist/carpal bones (reminder, the biceps is attached to the radial tuberosity)

In order to transfer force between the ulna and radius: interosseous membrane

Question 2

Explain which dermatomes stop at the wrist

Answer 2

C5 and T1 stop at the anterior wrist (they are on the anterior side)

C6, C7, and C8 run on the posterior sides of the arm, and then go down into the hand

Question 3

For the forearm:

the posterior compartment is innervated by the ___

The anterior compartment is innervated by the ____ or _____

Answer 3

FOREARM:
posterior compartment is innervated by radial nerve

Anterior compartment is innervated by either medial or ulnar nerve

Question 4

What nerves innervate the sensory forearm anteriorly?

Answer 4

Lateral antebrachial cutaneous nerve and the medial antebrachial cutaneous

Question 5

The _________ extends across the posterior radiocarpal (wrist) joint

Answer 5

The extensor retinaculum extends obliquely across the posterior radiocarpal joint