Final answer:
The presence of a fracture through the medullary cavity depends on the fracture's type and location. A complete bone break can penetrate the medullary cavity, affecting the bone's blood and nerve supply, and requiring emergency medical attention.
Step-by-step explanation:
Whether a fracture will pass through the medullary cavity depends on the type of fracture and the location of the bone affected. The medullary cavity is the central part of the bone where bone marrow is stored, surrounded by the harder compact bone. If a bone fracture, as described in Figure 14.5.4, is a complete break and significant enough, it can indeed pass through the compact bone and into the medullary cavity, disrupting the blood supply and nerve supply to the bone. This is because arteries nourishing the spongy bone and medullary cavity enter through the nutrient foramina located in the diaphysis, and a fracture that penetrates this area can compromise these structures.
Understanding the blood and nerve supply of bones is crucial when assessing a fracture's severity. The veins that collect blood from the marrow cavities after it nourishes the osteocytes could also be affected if a fracture penetrates through the compact bone and into the medullary cavity. Immediate medical treatment would be required to manage the injury and prevent further complications.