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Surgical Management of Symptomatic Cervical or Cervicothoracic Kyphosis Due to Ankylosing Spondylitis

Study Design. Literature review. Objective. To evaluate surgical management and outcomes in the treatment of severe chin-on-chest deformities due to ankylosing spondylitis (AS). Summary of Background Data. AS is a chronic inflammatory disease that can lead to severe flexion deformities involving the cervicothoracic spine. The resulting chin-on-chest deformity can be extremely debilitating. Methods. Literature search using PubMed database. Results. Six retrospective clinical studies were identified. No randomized or prospective studies were found. The indication for surgery was primarily loss of horizontal gaze. The most common surgical technique was based on the original Simmons osteotomy at C7–T1. Analysis of radiographic studies and the chin-brow to vertical angles demonstrated significant improvement in the flexion deformity in all cases after surgery. The complication rate was high, ranging from 26.9% to 87.5%, with a mortality rate of 2.6%. However, most complications were minor, and the permanent neurologic complication rate was 4.3%. All patients had improvement in horizontal gaze, and patient satisfaction after surgery appeared high. Conclusion. Based on these studies, it seems that for the severely impaired patient with loss of horizontal gaze, surgical correction is a reasonable option with a high likelihood of success.