No one knows the exact cause of osteoarthritis of the spine, but most people who develop osteoarthritis have at least one of the traits below.
Two main risk factors for developing osteoarthritis of the spine are advanced age and damage to a vertebral disc:
Advanced age. The prevalence of symptomatic facet joint osteoarthritis increases rapidly starting at age 45 and continues to increase thereafter. One study found signs of cervical facet joint osteoarthritis in 57% of adults older than 65 years. In another study, experts found evidence of osteoarthritis in the lumbar spines (lower backs) of 89% of subjects ages 60-69. The prevalence of spinal osteoarthritis increases with age because as years pass the facet joints experience wear and tear. Also, cartilage thins and becomes less flexible over time, making joints more prone to osteoarthritis. Damage to vertebral disc. A vertebral disc serves as a cushion between two vertebrae. Damage to a vertebral disc is a separate diagnosis than spine osteoarthritis; however, disc damage commonly leads to osteoarthritis. When a disc is damaged it reduces the space between the two adjoining vertebrae. This change can put excessive pressure on the affected facet joints, causing cartilage to wear away, resulting in osteoarthritis.
In addition to the above, other risk factors for developing spine osteoarthritis include:
Excess weight/obesity. Facet joints are weight-bearing joints and a person who is overweight or obese is more likely to develop osteoarthritis of the spine. In fact, people who are obese are 5 times more likely to develop osteoarthritis in the low back. Congenital defect or illness. Scoliosis or poor alignment of the spine can put more stress on the facet joints between vertebrae, increasing the risk of developing osteoarthritis of the spine. Episodes of gout or septic arthritis as well as metabolic disorders and other congenital conditions can also increase risk.
Trauma. A broken vertebra, serious back injury, or back surgery may cause joint damage that eventually leads to spinal osteoarthritis, although symptoms may not appear until many years later. Joint stress and chronic injury. People whose regular activities or jobs put recurring strain on their necks or backs (e.g. doing heavy lifting) can experience "mini-traumas" in their facet joints and are more likely to develop osteoarthritis in the spine. Athletes who participate in high impact sports (e.g. football) may also be more prone to developing spinal osteoarthritis. Gender. After age 45, women are more likely than men to develop osteoarthritis in the lumbar spine. Family history. Genetic factors for spinal arthritis have not been well studied; however, family history seems to be a risk factor for other types of osteoarthritis, such as hand, knee, and hip osteoarthritis. Similar to height and hair color, the likelihood of a person developing spinal osteoarthritis may be influenced by genetics. See When Hand Pain Is Osteoarthritis
While the above risks factors predispose certain individuals to osteoarthritis, they are not causative. Some people without the above risk factors may develop the condition and some people with all of the above characteristics may never develop it.
If back pain comes on suddenly, it is more likely to be caused by a strained muscle or other trauma or condition, and not by spinal osteoarthritis.