Human Anotomy and Physiology Case Study Example | Topics and Well Written Essays - 500 words

Human Anotomy and Physiology - Case Study Example The spine is made up of approximately 33 individual vertebrae; seven cervical, twelve thoracic, five lumbar, five sacral, and four coccygeal. In our 70 year old subject, this number is closer to 27 since the five individual bones of the sacrum have long since entirely fused into one unit. Similarly, the fused individual components of the coccyx can probably be considered as two bones. One of the first structures to appear during embryogenesis, the spine develops from the mesoderm layer and shares a common origin with the skin, muscles, and gonads. It continues to develop throughout infancy and puberty. Each vertebra of the spine is composed of minerals and protein. Calcium is the predominant mineral, with several others. Collagen and cartilaginous structures form the protein matrix of the bones. Calcium salts such as calcium phosphate in the form of hydroxyapatite are embedded in a collagen matrix containing osteocytes and vascular tissues. The vertebrae are mostly compacted bone, which supports the weight bearing function of these structures. Our post-menopausal subject is losing bone mass at a rate of about 1% per year (see Calcium). The spine is interdependent with the paraspinal muscle groups (longissimus, multifidus, and rotatores).