Compound Fracture Case Study

. What is a compound fracture? (2 points)

A compound fracture is a broken bone that protrudes through the skin.

2. What is the importance of the area of the fracture? What type of cells are found in this area? What type of growth occurs in this area? (6 points)

This kind of fracture can damage the surrounding muscles, tendons and ligaments. Therefore, the healing process will be longer. Appositional bone growth occurs in this area because the bone is being remodeled with an increase in diameter as new bone is being laid down. Osteoblasts, osteocytes and osteoclasts are the cells that would be found in this area to help with bone remodeling.

3. Describe the microscopic features of the osseous tissue that help long bones withstand compressive

Therefore, synovial fluid found in the joint helps minimize friction during extension and flexion of the knee because the viscous fluid functions as a lubricant to act as an absorber to prevent bones from hitting one another. Also, hyaline cartilage helps minimize friction by providing a smooth sliding area that still allows minimum movement of bone without hitting one another.

7. Describe the changes a broken bone undergoes as it is healing. ( 4 points)

When bone heals it undergoes four repair phases. First, hematoma forms blood clotting in the fracture. Second, a fibrocartilaginous (soft) callus forms. This is when the fibroblasts lay down collagen matrix to form cartilage. Third, hard callus forms when osteoblasts produce trabeculae and the callus is replaced by this bone. Bone will continue to grow and thicken. Finally, remodeling is the final phase of fracture repair. During the final phase osteoclasts remove excess bony material from both exterior and interior surfaces. Compact bone is now replaced by primary bone.

8. How does weight-bearing influence the bone repair process you described above? (i.e. what effect does weight-bearing have on the orientation of the Haversian systems?) ( 3