Diagnosing Osteoarthritis of the Spine

Physicians and surgeons at NYU Langone have extensive experience in diagnosing osteoarthritis of the spine, even when symptoms are mild. Osteoarthritis occurs when the spinal joints, called facet joints, deteriorate and become less functional. This condition usually results from aging, when the joints wear down after years of repeated everyday motions. Osteoarthritis of the spine is most common in people over age 40.

Degeneration of the facet joints often begins with the erosion of cartilage, a smooth tissue that lines the ends of bones in the joints and helps bones move together comfortably. If cartilage in the joint erodes, bones rub directly against each other, causing inflammation and irritation that lead to symptoms such as aching pain, often in the lower back or neck, and stiffness, which may limit mobility. For many people, pain and stiffness are most noticeable first thing in the morning or just before bed.

Repeated friction between bones can lead to the development of small bony growths called osteophytes, or bone spurs. These can get in the way of a nerve as it exits the spinal canal, creating what’s called a pinched nerve. When this occurs, compression may cause pain separate from the discomfort caused by osteoarthritis itself. Pain caused by a pinched nerve often travels, or radiates, down the legs or into the arms. You may also notice numbness, tingling, or weakness in the limbs. 

In some people with osteoarthritis, the intervertebral discs, which are thick layers of cartilage that rest in between the vertebrae, begin to lose fluid and shrink. This is called degenerative disc disease. The discs help the spine absorb the weight of the body during movement and stabilize the spine by maintaining even spaces between the bones. If the disc deteriorates, the space between the vertebrae narrows, which may lead to abnormal movement between the vertebrae, as well as changes in the shape of the spine.

Specialists at NYU Langone’s Spine Center use advanced diagnostic techniques to identify early signs of osteoarthritis of the spine and determine whether nerve damage may be contributing to your symptoms. 

Medical History

Details about your symptoms and medical history help doctors diagnose osteoarthritis of the spine. Your doctor asks you when you first noticed pain and stiffness, what time of day the pain is strongest, whether you feel tingling or numbness in your arms or legs, how much symptoms interfere with your everyday life, what medications you take, and whether you have other conditions that could affect the health of your spine. For example, prior spinal surgery can cause premature erosion of cartilage and contribute to the development of osteoarthritis.

Physical Exam

Doctors examine the area around your spine to look for pain or tenderness in the neck or lower back and evaluate the flexibility and range of motion of your spine. You may be asked to walk or bend so that your doctor can assess which motions produce pain and how significantly pain and stiffness affect your movements. 

If you feel tingling, numbness, or weakness in the arms or legs, a doctor may perform a neurologic examination to determine whether nerve damage is contributing to your symptoms. Nerves travel through the body, affecting muscles in predictable patterns. These patterns can help your doctor match physical responses with particular nerves. 

For example, your doctor may use a small hammer to test for abnormal reflexes in various parts of your body, which may indicate a pinched nerve. A doctor may also expose areas of your skin to stimuli such as warm and cool temperatures to assess whether sensation is affected.

X-rays

Doctors use X-rays to create images of bones in the spine while you are sitting down and standing up. Doctors examine these images to see whether osteoarthritis has affected the alignment of the spine or whether there is any unusual movement between the bones of the spine. Doctors also assess the space between the vertebrae. If the space has narrowed, a disc may have deteriorated. X-rays can also confirm the presence of bone spurs on the vertebrae.

MRI Scans

MRI scans use magnetic fields and radio waves to create detailed images of the soft tissues inside the body. These include cartilage, nerves, and discs. Doctors use MRI scans to look for evidence of disc degeneration that may not appear on an X-ray and for signs of a pinched nerve.

Electromyogram 

If you feel pain radiating into your arms or legs, or weakness, tingling, or numbness, an electromyogram, or EMG, can show whether nerves are being pinched as a result of osteoarthritis of the spine. An EMG measures the electrical impulses transmitted along nerves, nerve roots, and muscles. This test helps doctors determine whether pain or weakness originates in muscles or in nerves.

During an electromyogram, a doctor inserts small needles, or electrodes, through the skin and into muscles that correspond to specific nerves. The needle pricks are not very painful, but the sensation may feel a bit strange. Your doctor then asks you to move these muscles one at a time. The signals recorded when the muscles contract can indicate which nerve roots are affected and whether muscle has been damaged by nerve injury.

An electromyogram is relatively painless, though some people are uncomfortable with the needles. Usually, the test takes about 15 to 30 minutes to complete.