Ankylosing Spondylitis (AS) is an inflammatory condition that is seen more typically in young men ( age 20 to 40 years) that causes inflammation of the joints in the spine and those connecting the pelvis, the sacroiliac joints. Over time, the spine fuses, or welds together into one long piece that is immobile and rigid. Most patients with AS are positive for the HLA-B27 antigen which can be detected with a blood test.
Lower back pain is a common initial symptom, followed by stiffness and an inability to bend forward. Symptoms usually begin between the ages of 20 and 40 years.The spine develops kyphosis (bent forward position) in the cervical, thoracic and lumbar spine and may prevent the patient from being able to look straight ahead. The chin can become locked onto the chest, and limit the patient's ability to look up. This deformity can severely affect normal activities of daily life.
There is usually a family history which helps narrow the diagnosis. Most patients with AS are positive for the HLA-B27 antigen which can be detected with a blood test. Most patients are referred to a Rheumatologist for evaluation and treatment. X-rays of the spine and pelvis will be performed. Initially the x-rays may be negative in younger patients, but will later show the findings of a fused spine and fusion of the sacral iliac joints in the pelvis.
Treatment of AS is through medical management unless severe deformity develops. Non-steroidal anti-inflammatory drugs (NSAIDS) are frequently prescribed as well as newer forms of medications such as the TNF inhibitors (etanercept, adalimumab, infliximab). If a severe kyphotic deformity develops that prevents a patient from being able to walk in an upright position or look upright with a horizontal gaze, then spinal surgery may be recommended. The surgical treatment consists of procedures called osteotomies where a wedge of the spine is removed to help straighten it into a more upright position.