In: Anatomy and Physiology
Mrs. Debbie Morgan is a 45-year-old female who works as a stocking clerk for a local home improvement store. While she was at work today a large box of metal rivets fell from a 20-ft.-high overhead shelf, striking her outstretched arm and knocking her to the ground. The ambulance personnel reported that she had lost quite a bit of blood at the accident scene and was “knocked out” when they arrived. To minimize further hemorrhage, the paramedics applied a pressure bandage to her arm.
You meet the paramedics as they bring Mrs. Morgan into the emergency room and begin to assess her for injuries. She is awake and alert, but complaining of severe left arm and back pain, plus she has a “killer headache.” To fully examine her injuries you remove four blood-soaked bandages from her arm. You notice a large open wound on her arm with what appears to be bone tissue sticking out of the skin. She also has bruises covering her left shoulder, left wrist, and lower back. To determine the extent of her injuries Mrs. Morgan undergoes several x-rays, which reveal the following:
1) bones are classified as flat, long, short, and irregular bones based on their shape.
Bones fractured here are humerus which is a long bone, the occipital bone which is flat, and vertebra which is an irregular bone
2) The vertebral body is composed of cancellous bone, which is the spongy type of tissue
3) The spongy bone is made up of trabeculae (small beam) that have an open arrangement of osseous tissue, which helps decrease the weight of bone and prevent breakage.
4) The diaphysis is the shaft of long bones age contains an outer cortical shell of dense compact bone and an inner medullary cavity of spongy bone.
5) Long bones has both an outer and inner connective tissue covering. Outer connective tissue of bone is called periosteum. Beneath this in the diaphyseal segment of long bone is a thick shell of cortical bone or compact bone. Inside cortical bone is a medullary cavity of spongy bone containing Haversian and Volkman's canals that carries neurovascular structures.
The inner connective tissue layer of bone is called a endosteum that lines the inner side of the cortical bone as well as the trabeculae of spongy bone including the canals.