Myelopathy associated with instability consequent to resection of ossification of anterior longitudinal ligament in DISH

Abstract

Purpose: The presence of prominent OALL (ossification of anterior longitudinal ligament) in the anterior cervical spine has been implicated as a cause of dysphagia. Surgical resection of the OALL is considered effective for the management of diffuse idiopathic skeletal hyperostosis (DISH)-related dysphagia. Although many reports have been published on DISH-related dysphagia, no cases of postoperative cervical instability have been reported thus far. We present a case in which the patient developed myelopathy associated with instability consequent to resection of OALL in DISH.

Methods: A 62-year-old man presented with progressive dysphagia that persisted for a year. The patient's symptoms were successfully resolved by resection of OALL. Five years after the surgery, the dysphagia resurfaced and was found to be caused by the regrowth of the OALL. A repeat surgery was performed, and the dysphagia disappeared. Eleven months after the second surgery, he visited the hospital with progressive quadriparesis and pain in the cervical region.

Results: Nine-month follow-up radiologic study revealed cervical instability at the level of C5-6 resulting in myelopathy. The patient underwent decompressive laminectomy and posterior fusion surgery.

Conclusion: Surgical resection of DISH-related dysphagia typically yields excellent outcomes, but our experience in this case highlights the possibility of OALL regrowth and subsequent cervical instability after resection of OALL.

Keywords: Cervical instability; Diffuse idiopathic skeletal hyperostosis; Myelopathy; Resection of OALL.