Spinal Degeneration Due to Aging
Why Does Spinal Fracture Risk Increase With Age?
Like eyesight or hearing that may diminish over time, the human spine also undergoes change as the body ages. While aging is inevitable, the rate at which each person’s spine shows the effects of aging is unique.
During childhood and early adulthood, the body creates new bone faster than it absorbs existing bone, a process that starts to reverse around age 30. Bone loss in women speeds up when estrogen production slows down, usually between the ages of 45-55. Likewise, men begin to experience bone loss as their production of testosterone declines, generally around age 45-50. As bone mineral content declines, bone gradually loses density and becomes more fragile.
What Are the Signs of an Aging Spine?
Some people live to old age without experiencing any of the symptoms typically associated with an aging spine. Others may experience the following:
- Loss of bone density
- Spinal fracture, even from minor trauma
- Decreased range of motion in the joints: difficulty bending, twisting, or walking
- Discomfort or pain after long periods of sitting or standing
- Difficulty getting up from a sitting position
- Difficulty lifting heavy objects
- Loss of flexibility
- Increased susceptibility to back problems in colder weather
What Factors Can Affect Spinal Degeneration?
Each person's body is different. In addition to genetic history, the following also play in a role in determining how the spine and its surrounding structures age:
- Activity level
Why Are Women Are More Susceptible to Spinal Degeneration?
Women are more vulnerable to disorders arising from spinal degeneration because their bones are typically smaller and lighter than their male counterparts. In addition, loss of bone mass accelerates as estrogen levels decline, especially in the first five to eight years after menopause. Women make up 80% of patients diagnosed with osteoporosis.
Women with low body weights also are also at risk for conditions associated with an aging spine. Excessive dieting or eating disorders, like anorexia nervosa, can contribute to bone loss. Thin women have less body fat and therefore produce less estrogen—a hormone that can help prevent bone loss in post-menopausal women.
What Other Conditions Are Commonly Associated With An Aging Spine?
Osteoporosis—Osteoporosis is a common bone condition characterized by decreased bone mass and the deterioration of bone tissue. Often called "the silent thief", osteoporosis progresses without symptoms until a fracture occurs. It occurs most often in weight-bearing bones such as the hip and spine, but can affect any bone in the body. With osteoporosis, bones become porous, brittle, and susceptible to fracture. The spine is particularly vulnerable—in fact, vertebral compression fractures (also referred to as spinal fractures) are common in patients with severe osteoporosis. A humped back—or dowager’s hump—is an obvious sign of severe osteoporosis.
Disc Degeneration—The spine consists of bones (vertebrae) and discs (spongy, cartilaginous pads located between each vertebra) that serve as cushions for the vertebrae. At birth, the discs are comprised primarily of water. Throughout youth and early- to mid-adulthood, flexion of the torso and spine keeps water moving through the discs, drawing nutrients in and flushing waste products out. This keeps the discs strong, flexible and healthy.
As the spine ages, the intervertebral discs gradually become more fibrous and inflexible. This fibrosis and stiffening affect the discs' ability to process water. They become progressively more dry and brittle, due to dehydration, and lose their shock absorbing qualities. Some degree of disc degeneration is normal; however, problems can occur when discs pinch or place pressure on adjacent nerve roots and/or the spinal cord.
The most common early symptom of a problem related to disc degeneration is usually pain in the back that radiates to the buttocks and upper thighs.
Osteoarthritis—Osteoarthritis is the most common form of arthritis, and most frequently occurs in weight bearing joints. Spinal osteoarthritis affects the vertebral facet joints that enable the spine to bend and twist. As the facet joints deteriorate, cartilage may become inflamed and eventually start to break away from the joint surfaces. Vertebrae begin to rub together, and the surrounding nerves and tissues can become inflamed, making movement painful. Osteoarthritis also may trigger the formation of osteophytes (bony spurs), which can cause the spinal disc space to narrow, and the affected disc to collapse.
Spinal Stenosis—Spinal stenosis is a narrowing of one or more areas in the spine—most often the lower back. This narrowing can put pressure on the spinal cord or on the nerves that branch out from the compressed areas. This can lead to a number of problems, depending on which nerves are affected. In general, spinal stenosis causes cramping, pain or numbness in the legs, back, neck, shoulders or arms; loss of sensation in the extremities; and sometimes problems with bladder or bowel function.