The dissection of the arm and forearm is relatively straight forward and is best approached according to the compartments of each region since these compartments describe muscles with common functions and common innervation.

Basic concepts:
You may wish to review the basic concepts for the upper limb at this time. The link opens a new window which you will need to close to return to this page.

Specific Learning Objectives:

1. Define the venous drainage (both superficial and deep).
2. Recall the cutaneous innervation of the arm, forearm. Compare and contrast a dermatome with the cutaneous innervation of specific nerves.
3. Illustrate that each part the upper limb has compartments formed by the deep fascia.
4. Summarize the functions of muscles in each of the compartments. Knowing the functions helps you learn the attachments (origins and insertions) of individual muscles.
5. Explain the rotator cuff.
6. Recall which spinal segments contribute to each peripheral nerve (e.g., ulnar = C8, T1).
7. Describe the innervation of each compartment and the specific deficits that occur with lesions of individual nerves at different parts along the course of each nerve. What actions will test the musculocutaneous, median, ulnar and radial nerve functions? Where can the above nerves be checked for sensory loss? What is the significance of wrist drop, claw hand?
8. Describe the vascular pattern and major arteries. Describe the major anastomoses around each joint.
9. Identify anatomic structures in radiographic studies including X-ray, CT scans and MRI films.

Difficult parts of the dissection:

1. Dissecting the common interosseus artery and its anterior and posterior branches takes patience and careful separation of the muscles. DO NOT cut muscles/tendons since this destroys the anatomy of the region.
2. Exposing the radial nerve around the posterior arm requires an understanding of the anatomy of the triceps brachii muscle. See your previous dissection of the arm for detailed instructions. This is an exception to the rule of not cutting muscles. Remember, the artery that follows the radial n. is the profunda brachii a. Relationships, relationships, relationships!