Ankylosing Spondylitis

Ankylosing spondylitis is an inflammatory condition that involves the spine and skeleton of the head and trunk. The disorder causes inflammation and pain in joints in the spine, pelvis and other parts of the skeleton. In addition, parts of the spine, the hips or the sacroiliac joints where the hips join the lower back, may fuse, or grow, together.

Symptoms of ankylosing spondylitis include:

  • Pain
  • Stiffness, especially in the morning
  • Functional limitation

When the disorder affects the spine, it also may result in progressive deformity including curvature of the back, called kyphosis, and the inability to stand up straight.

The first clue in diagnosing ankylosing spondylitis is the presence of symptoms, especially back pain. In addition, X-rays are taken to look for signs of the disorder, such as fused joints. A blood test for the HLA-B27 gene, which is found in about 90 percent of the people with ankylosing spondylitis, also may be performed. However, only 10 percent to 15 percent of people who inherit the gene develop ankylosing spondylitis.

Ankylosing spondylitis usually is treated with:

  • Pain or anti-inflammatory medications
  • Antirheumatic drugs
  • Exercise
  • Physical therapy

Our experts are currently working with new medications that inhibit immune-system cells, called cytokines, which appear to cause some of the symptoms of ankylosing spondylitis.

Joint replacement surgery, most commonly of the hips and shoulders, may be an option for severely affected patients. In addition, spinal reconstruction and internal bracing may be necessary to treat severe spine deformities associated with ankylosing spondylitis.

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Reviewed by health care specialists at UCSF Medical Center.

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UCSF Clinics & Centers

Ankylosing Spondylitis
400 Parnassus Ave., Floor B1
San Francisco, CA 94143
Phone: (415) 353–2305
Fax: (415) 353–2530
Appointment information

Arthritis & Joint Replacement Center
1500 Owens St., Suite 430
San Francisco, CA 94158
Phone: (415) 353–2808
Fax: (415) 885–3862
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Spine Center
400 Parnassus Ave., Third Floor
San Francisco, CA 94143-0332
Phone: (866) 81-SPINE or
(866) 817-7463
Neurospine : (415) 353-2739
Neuro-spine Fax: (415) 353-2176
Ortho-spine Fax: (415) 353-4047
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