Porth's Essentials of Pathophysiology, 4e

Structures of the Skeletal System Cartilage Types of Cartilage Repair of Hyaline Cartilage Bones and Bone Structure Classification of Bones Parts of a Long Bone Bone Tissue Blood Supply Bone Cells Bone Formation, Growth, and Remodeling Bone Growth in Childhood Bone Remodeling Hormonal Control of Bone Formation and Metabolism Joints Fibrous Joints (Synarthroses) Cartilaginous Joints (Amphiarthoses) Synovial Joints (Diarthroses) Ligaments and Tendons Joint Vasculature and Innervation Bursae and Tendon Sheaths 12 U N I T

Musculoskeletal Function

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C h a p t e r

ithout the skeletal system, movement in the exter- nal environment would not be possible. The bones of the skeletal system serve as a framework for skeletal muscle attachment and movement; protect and maintain vital structures in their proper position, provide stability for the body, and maintain the body’s shape. The skeletal system also serves as a reservoir for ions such as calcium, phosphorous, and magnesium, and it houses the hemato- poietic connective tissue in which blood cells are formed. Structure and Function of the Skeletal System W The skeletal system can be divided into two functional parts—the axial and appendicular skeletons (Fig. 42-1). The axial skeleton , which is composed of the bones of the skull, thorax, and vertebral column, forms the axis of the body. The appendicular skeleton consists of the bones of the upper and lower extremities, includ- ing those of the shoulder and hip girdles. In addition to bones, the skeletal system includes cartilage and liga- ments that join bones together at joints, giving the body flexibility and allowing movement to occur. Two types of connective tissue are found in the skel- etal system: cartilage and bone . They both have living cells that secrete the extracellular matrix in which their cells are housed. The extracellular matrix in cartilage is firm but also somewhat pliable, providing the resilience needed for cushioning of bony structures. In contrast Structures of the Skeletal System

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