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Atlantoaxial Osteoarthritis: A Well-Established Entity that Remains Frequently Overlooked
Matthew T Neal1, Wende Gibbs, Mark K Lyons
1Mayo Clinic Arizona, Department of Neurological Surgery, Phoenix, Arizona, USA.
Abstract:
Painful atlantoaxial (C1-2) osteoarthritis (AAOA) has been described over 40 years ago. The condition may cause severe pain symptoms and disability related to the unilateral suboccipital pain and, in some cases, occipital neuralgia. One of the greatest challenges with AAOA is making the diagnosis. Diagnosis is commonly missed or delayed when headaches are treated in isolation or when pain is attributed to subaxial spondylosis. Here we present an illustrative case involving a 67-year-old male presenting with classic painful AAOA. After failing conservative treatments, he was evaluated with morphologic, radiological studies and a diagnostic injection. He was successfully treated with bilateral, navigation guided C1 lateral mass and C2 pedicle screw fixation and fusion. To conclude, when there is clinical suspicion for painful AAOA, providers have numerous diagnostic modalities, including newer hybrid techniques, that can be used to solidify the diagnosis. When conservative efforts fail, C1-2 fusion is an effective and enduring treatment for most patients.
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