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Some degree of osteoarthritis of the spine is common in middle-aged people, even if they are not aware of it. OA of the spine can take several forms. In ankylosis, parts of the spine are abnormally fused together as a result of bony overgrowth. For example, bony spurs can fuse vertebral bodies together. The peripheral nerves formed from the spinal cord exit the bony spine through recesses in vertebrae called intervertebral foramina (see Figure 2 below). Some of these foramina can become encroached by osteoarthritis and require surgical decompression. Vertebrae have contact points with other vertebra called facet joints (see Figure 3 below). Arthritis affecting these facet joints can be painful and limit the motion of the spine.

figure 2

figure 3

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