We begin your dissections with the back for 2 major reasons. First, structures tend to be large and easily defined. Second, it gives students opportunities to learn basic dissection techniques without endangering many anatomical structures.

Specific Learning Objectives:

1. Recognize the boundaries of each of the triangles of the back and explain their clinical significance.
2. Compare and contrast 'true' back muscles from the overlying superficial muscles.
3. State the functions of each group of muscles, which will describe their bony attachments.
4. State the nerve supply of each muscle.
5. Describe the vascular supply of the region.
6. Summarize the suboccipital region and the relationship of the vertebral artery and greater occipital nerve.
7. Describe the relationship of the atlas and axis to the skull.
8. Explain the composition of peripheral nerves (e.g., greater occipital n. is strictly sensory).
9. Identify anatomic structures in radiographic studies including X-ray, CT scans and MRI films.

1. Locate the spinal accessory nerve (C.N.XI), which can be easily cut where it is superficial at the superior border of the trapezius. See Step 2. Clean the nerve superiorly and inferiorly.
2. The suboccipital triangle is particularly challenging because the structures are deep and in a tight area. Adequate dissection of this area requires that the superficial muscles (trapezius, splenius, semispinalis) be reflected far enough laterally that you can easily palpate the transvers processes of C1. See Step 4.