The major age related change in the skeletal system is the loss of calcium in the bone.\u00a0 As previously discussed calcium homeostasis is critical to maintaining bone structure.\u00a0 As one ages this homeostasis is disrupted, which results in a weakening of the bones.\u00a0 While the exact causes of the disruption are not fully understood it has been observed that bone loss is more severe in women that men.\u00a0 In women bones begin to lose calcium around the age of 30.\u00a0 By the age of 70 women may have lose 30% or more of their bone calcium.\u00a0 Most men don’t begin to the lose calcium until they reach the age of 60.<\/p>\n
In addition to the lose of calcium as one ages protein synthesis also slows.\u00a0 As a result there is little to no new\u00a0formation of collagen fibers.\u00a0 These\u00a0fibers are what give the bones strength and flexibility.\u00a0 Without them\u00a0bones become brittle resulting in a higher rate of fracture.<\/p>\n
Finally bone reabsorption continues without the\u00a0continued formation of new bone.\u00a0 This results in larger centrally located medullary cavities\u00a0of the long bones and thinner walls of compact bone.<\/p>\n
All of these changes result in a decrease of bone mass.\u00a0 While the causes of these changes are not well understood, it is thought that hormonal imbalances and changes in activity level may be factors.<\/p>\n
One of the main roles of the skeletal system is the smooth functioning of the various movable joints of the body.\u00a0 Articular cartilage covers the ends of bone involved in a joint.\u00a0 As the joint moves articular cartilage rubs against articular cartilage, as opposed to bone on bone contact.\u00a0 This\u00a0 cartilage reduces friction and produces smooth movements in the joints.\u00a0 As you age this cartilage becomes thinner and deteriorates.\u00a0 The resulting bone on bone contact makes movement of the joint painful.<\/p>\n
Costal cartilage has the specific function of connecting the ribs to the sternum.\u00a0 This cartilage make it possible\u00a0for the rib cage to expand and contract with respiration.\u00a0 As one ages the cartilage calcifies resulting in a loss of flexibility.\u00a0 This restricts breathing.<\/p>\n
Fibrocartilage makes up the intervertebral discs which specifically provides cushioning between the vertebrae which make\u00a0up the spinal column.\u00a0 After the age of about 40 years of age, the\u00a0cartilage experiences a gradual loss of cells and water.\u00a0 This results in a decreased level of cushioning provided by these discs.<\/p>\n\n\t\t\t Candela Citations<\/h3>\n\t\t\t\t\t