Permission is granted to print and distribute this excerpt for noncommercial use as long as the above source is included. The information in this article is meant to educate and should not be used as an alternative for professional medical care. Without the regular loading of weight from walking, bones begin to lose calcium. This leads to osteoporosis, in which bones become more brittle and prone to fracture. The hips are a common site of fracture, as are the legs, spine, and arms.
Osteoporosis occurs with aging in some people, particularly in post-menopausal women.
Risk is increased with diabetes, vitamin D deficiencies, or diets low in calcium. Smoking and alcohol abuse aggravate the condition, as do lack of activity and sunlight. People with traumatic disabilities such as traumatic brain injury, spinal cord injury, or amputation tend to spend an extended initial period in bed, which invites osteoporosis to begin. Apparently spinal cord injury has its own biochemical effect on osteoporosis, although the mechanism is not clear. It has been observed that calcium and other minerals from the bones are lost through the urine at a more rapid pace after spinal cord injury.