Thorax Lab Guide

Osteology of the Thorax

Learning Objectives

Appreciate that studying the bones (osteology) of a region forms a solid foundation for understanding and remaining oriented in that region (i.e. bony landmarks can help you find and identify soft-tissue structures in the body).
Know the main bony landmarks that can be palpated on the outside of the thorax. These landmarks will be important for making the correct scalpel incisions to start the thorax dissection.
Be able to identify true ribs, false ribs and floating ribs on an articulated skeleton.

Instructions

Both A and B dissection groups should work through this osteology section with the mounted skeletons in the lab during the first lab.

Osteology

The study of each region of the body includes study of the bones (osteology) of that region. You should come to each lab having looked over the osteology and gained a basic understanding of the bones of the region. However, it is unrealistic to expect to completely learn all the details of osteology in one sitting. Learning anatomy is an iterative process; with repeated study in and out of lab you will come to understand more and more of the details of anatomy.

In addition to studying before you come into lab, you should also review the osteology again at the end of each lab. The idea is that since bones form the structural framework for the body, after a dissection, you should be able to better see the bones in the cadaver and refer to an articulated skeleton to understand the “core” of the anatomy.

On an articulated skeleton, identify the following:

Sternum

Osteology of the clavicle and scapula (posteriolateral view)

Osteology of the clavicle and scapula (anterior view)

Surface anatomy of the anterior chest (female)

Osteology of the thorax (anterior view)

PUTTING IT ALL TOGETHER

The acromioclavicular joints, the acromion process, the jugular notch, the sternal body and the xiphoid process are all palpable through the skin. Thus, these are used as surface landmarks and are palpated during musculoskeletal exams. Start thinking about where to find these landmarks on your cadaver.

Ribs - Identify the following on an articulated skeleton:

Posterior view of the rib cage.

Anterior view of the rib cage.

Lateral view of the right half of the rib cage.