Many people with spondylosis on X-ray do not have any symptoms. In fact, lumbar spondylosis (spondylosis in the low back) is present in 27%-37% of people without symptoms. In some people, spondylosis causes back pain and neck pain due to nerve compression (pinched nerves). Pinched nerves in the neck can cause pain in the neck or shoulders and headache. Nerve compression is caused by bulging discs and bone spurs on the facet joints, causing narrowing of the holes where the nerve roots exit the spinal canal (foraminal stenosis). Even if they are not large enough to directly pinch a nerve, bulging discs can cause local inflammation and cause the nerves in the spine to become more sensitive, increasing pain. Also, disc herniations can push on the ligaments in the spine and cause pain. If new nerves or blood vessels are stimulated to grow from the pressure, chronic pain can result. Because of the pain, the local area of the spine may attempt to splint itself, resulting in regional tenderness, muscle spasm, and trigger points.
Characteristic findings of spondylosis can be visualized with X-ray tests. These findings include decrease in the disc space, bony spur formation at the upper or lower portions of the vertebrae, and calcium deposition where the vertebrae have been affected by degenerative inflammation.
Symptoms of spondylosis include localized pain in the area of spondylosis, usually in the back or neck. Spondylosis in the cervical spine (neck) can cause headache. However, it is controversial whether more mild spondylosis, such as small bone spurs and bulging discs that do not compress nerves, causes back pain. This is because most middle-aged and elderly people have abnormal findings on X-ray tests of spondylosis, even when they are completely pain free. Therefore, other factors are likely major contributors to back pain.