8.0 Introduction

This photograph shows a dancer striking a pose.
Figure 8.0.1 – Dancer: The appendicular skeleton consists of the upper and lower limb bones, the bones of the hands and feet, and the bones that anchor the limbs to the axial skeleton. (credit: Melissa Dooley/flickr)

Chapter Objectives

After this chapter, you will be able to:

8.1 Describe the bones of the pectoral girdle, and describe how the girdle unites the upper limbs with the axial skeleton

8.2 Describe the bones of the upper limb, including the bones of the arm, forearm, wrist, and hand

8.3 Describe the bones of the pelvic girdle, and describe how the pelvis unites the lower limbs with the axial skeleton.

8.4 Describe the bones of the lower limb, including the bones of the thigh, leg, ankle, and foot

8.5 Describe the embryonic formation and growth of the limb bones

Your skeleton provides the internal supporting structure of the body. The adult axial skeleton consists of 80 bones that form the head and body trunk. Attached to this are the limbs, whose 126 bones constitute the appendicular skeleton (Figure 8.0.2). These bones are divided into two groups: the bones that are located within the limbs themselves, and the girdle bones that attach the limbs to the axial skeleton. The bones of the shoulder region form the pectoral girdle, which anchors the upper limb to the thoracic cage of the axial skeleton. The lower limb is attached to the vertebral column by the pelvic girdle.

This figure shows the human skeleton. The left panel shows the anterior view, and the right panel shows the posterior view.
Figure 8.0.2 – Axial and Appendicular Skeletons: The axial skeleton forms the central axis of the body and consists of the skull, vertebral column, and thoracic cage. The appendicular skeleton consists of the pectoral and pelvic girdles, the limb bones, and the bones of the hands and feet.

Because of our upright stance, different functional demands are placed upon the upper and lower limbs. Thus, the bones of the lower limbs are adapted for weight-bearing support and stability, as well as for body locomotion via walking or running. In contrast, our upper limbs are not required for these functions. Instead, our upper limbs are highly mobile and can be utilized for a wide variety of activities. The large range of upper limb movements, coupled with the ability to easily manipulate objects with our hands and opposable thumbs, has allowed humans to construct the modern world in which we live.


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Anatomy & Physiology Copyright © 2019 by Lindsay M. Biga, Staci Bronson, Sierra Dawson, Amy Harwell, Robin Hopkins, Joel Kaufmann, Mike LeMaster, Philip Matern, Katie Morrison-Graham, Kristen Oja, Devon Quick, Jon Runyeon, OSU OERU, and OpenStax is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License, except where otherwise noted.