Skeletal trauma: Nursing pathophysiology

Skeletal trauma occurs when there’s an injury to the bones or joints. Common conditions include fracture, which is a complete or incomplete break in the bone; subluxation, when there’s partial separation of a bone from a joint; and dislocation, when there’s a complete separation of a bone from the joint.

Within the skeletal system, bones and joints work together with other tissues to provide structure, support, protection for internal organs, and to facilitate body movement. In addition to these functions, bones are metabolically active tissues that are involved in key functions in the body. First, long bones, such as the humerus or the tibia, contain marrow, the site where hematopoiesis occurs, which is the production of red blood cells, white blood cells, and platelets.

Bones also serve as a reservoir for calcium and phosphate phosphorus and play a key role in calcium homeostasis. Lastly, bones are continually involved in remodeling, which involves bone resorption, formation of new bone, and bone repair. This is accomplished through cells called osteoclasts, which break down old bone for reabsorption, and osteoblasts, which lay down new bone to replace the bone that was resorbed. This continual remodeling helps maintain the health and functionality of bones.

The basic types of bone are cortical, or compact bone, which is found in the outer layer of bones; and cancellous, or spongy bone, which is found in the interior of bones. The structure of cortical bone helps it to tolerate compression and shearing forces, while cancellous bone is better equipped to absorb and distribute stress throughout the bone.

Now, joints are the place where two or more bones come together, and they provide varying degrees of range of motion. For example, fibrous joints, like those between the bones of the skull, barely move at all; whereas, synovial joints, like those of the shoulders and hips, move more freely. Joints are supported by cartilage, ligaments, and tendons, which help stabilize them and facilitate movement.