Hint: Juvenile ankylosing spondylitis has its own codes. Narrow down your ICD-10 code choice options for ankylosing spondylitis by focusing on the exact location of the condition. Don’t forget that juvenile conditions have their own dedicated codes. First Look to Ankylosing Spondylitis Definition Ankylosing spondylitis is an arthritic disorder of the spine. Although the exact cause of ankylosing spondylitis is not known, experts believe that a patient’s genetics influences this condition. In fact, many patients with ankylosing spondylitis test positive for the gene HLA-B27. Patients affected by ankylosing spondylitis are usually young adults in their late twenties or early thirties, and men are more likely to develop this condition than women. Any region in the spine can be affected by ankylosing spondylitis, and a patient with this disease usually experiences pain and stiffness of the back, mainly in the low back, buttocks, and sacroiliac joints. Patients may also experience pain in their ligaments and tendons, fever, fatigue, loss of appetite, and eye inflammation. The patient’s vertebrae may fuse together, resulting in spinal stiffness and limited mobility. The patient may also develop a stooped posture and face challenges performing daily routine activities. Diagnosing: The physician diagnoses ankylosing spondylitis based upon the patient’s history, a physical exam, imaging techniques like x-rays and magnetic resonance imaging (MRI), as well as a lab test of inflammatory markers and genetic testing for the presence of HLA-B27. Treatment options: Treatment for ankylosing spondylitis includes nonsteroidal anti-inflammatory drugs, or NSAIDs, and disease modifying antirheumatic drugs, or DMARDs, to reduce inflammation and relieve pain. Also, the physician may recommend physical and occupational therapy, exercise, and joint replacement surgery, if necessary. Choose These Dx Codes for Ankylosing Spondylitis When reporting ankylosing spondylitis, you must first check the medical documentation for the specific site because ICD-10 offers numerous codes for this condition. When the patient has ankylosing spondylitis in the posterior lower part of the skull at the junction of the head with the neck, you should report M45.1 (Ankylosing spondylitis of occipito-atlanto-axial region). Then, according to the location of the inflammation in the spinal segment, you should report the following codes: Remember These Codes for Spinal Junctions If the neurosurgeon documents that the patient’s inflammation involves two spinal junctions, then you will have several ICD-10 choices. For example, if the patient has ankylosing spondylitis of the cervicothoracic region, you should report M45.3 (Ankylosing spondylitis of cervicothoracic region) for this condition. This is a situation where the inflammation involved two spinal junctions, in this case, the cervical and thoracic regions. Don’t miss: You may also see two other codes involving spinal junctions in the medical documentation for ankylosing spondylitis. For the thoracolumbar region of the spine, you should report M45.5 (Ankylosing spondylitis of thoracolumbar region). And for the lumbosacral region of the spine, you should report M45.7 (Ankylosing spondylitis of lumbosacral region). Do This When a Physician Documents Multiple Sites in Spine You may also have to submit a claim where the patient has ankylosing spondylitis in more than two regions of the spine. If the surgeon documents that more than two regions or junctions in the spine are affected by the disease, you should report M45.0 (Ankylosing spondylitis of multiple sites in spine). Use M08.1 for Juvenile Ankylosing Spondylitis You must also know the patient’s age when reporting ankylosing spondylitis because you will report M08.1 (Juvenile ankylosing spondylitis) for juvenile ankylosing spondylitis. Remember: Don’t forget to attach documentation to support the patient’s age when submitting a claim for M08.1 (Juvenile ankylosing spondylitis).