Biology 122 Spring, 2008

Laboratory 3

The Scapula, Shoulder and Axilla

OBJECTIVES

At the end of this laboratory you should:

1. Know the anatomic names applied to the regions of the upper limb. Relative to the shoulder, understand the general position of the deltoid, pectoral, scapular and interscapular regions and, relative to the clavicle, the supraclavicular and infraclavicular regions.

2. Know the names and be able to identify the bones of the upper limb. The carpals, metacarpals and phalanges will be studied later.

3. Be able to identify the following parts of the scapula on an isolated bone and in radiographs of the shoulder: medial or vertebral border, lateral border, superior border, spine, acromion, scapular notch, supraspinatus and infraspinatus fossae, subscapular fossa, glenoid cavity, superior angle, inferior angle, neck, coracoid process. Also know the position of and be able to appreciate the position of these parts in living subjects.

4. Be able to identify the position of the sternal and acromial ends of the clavicle and the associated joints and ligaments on the body, articulated skeleton, isolated bone and in radiographs. In addition, study the important relationship of the clavicle to the first rib and to adjacent soft structures (subclavian artery and vein, subclavius muscle).

5. Know the following bony landmarks on the humerus: head, neck, surgical neck, greater tubercle, lesser tubercle, greater and lesser tubercular crests, deltoid tuberosity.

6. Be able to describe the structure, function, and clinical significance of the glenohumeral (shoulder) joint, the rotator cuff (and muscles that contribute to it) and the subacromial bursa.

7. Know and be able to demonstrate the movements that occur at the shoulder and the joints where these movements occur.

8. Know the names, position, function and innervation of the posterior muscles of the shoulder. Understand the deficit(s) that would result if an individual muscle were paralyzed.

9. Understand the position and function of the pectoralis major and minor and their contribution to the shape of the anterior thoracic wall and axilla and to movements of the shoulder and arm.

10. Know the basic structures associated with the breast of the female.

11. Have a basic understanding of the structure and function of lymphatic system (vessels and nodes) and a specific knowledge of the “lymphatic watershed” as it applies to the skin of the body as a whole and especially to the breast. You should also understand the role of the lymphatics in the metastatic spread of infections and cancer.

PRELAB PREPARATION

1. Continue to study those portions of your textbook that deal with introductory material. At this time concentrate on the definition of movements and a review of those chapters dealing with muscle, tendons, and fascia.

2. Read the chapter in M&D on the basic structural plan of limbs and portions of the chapter on pectoral region, axilla and shoulder that pertain to this dissection (pp. 93-95; 725-734; 742-773, 781-784). Read the section on the shoulder joint (pp. 848-859).

3. Read about the lymphatic system in your textbook (pp. 44-47).

4. Review the osteology of the shoulder.