Sternum-splitting Anterior Approach Following Posterior Decompression and Fusion in Patients with Massive Ossification of the Posterior Longitudinal Ligament in the Upper Thoracic Spine: Report of 2 Cases and Literature Review

Purpose: Anterior approach to the upper thoracic spine is difficult. It is important for spine surgeons to know the indication and the effect of anterior decompression for upper thoracic lesions and also to recognize the complications which are related to the approach with sternotomy. We present two patients for whom we took the sternum-splitting anterior approach for thoracic ossification of the posterior longitudinal ligament (OPLL) following posterior decompression and fusion surgery; the clinical course and surgical outcome are discussed, with particular reference to complication avoidance and also we review the previous literature.

Methods: We present two cases with severe upper thoracic OPLL. The maximum occupying ratio of OPLL against the spinal canal was more than 80% in both cases. Posterior decompression and fusion were not effective and, therefore, anterior surgery with sternotomy was carried out.

Results: Cerebrospinal fluid leak was encountered with the removal of OPLL using the anterior approach. Subsequently, a polyglycolic acid sheet was used to cover the defect in the dura matter; a thoracic drainage system with a continuous suction unit was positioned at the surgical wound to avoid fluid retention in the mediastinum. In addition, we facilitated spinal drainage from the lumbar level. These procedures resulted in no complication caused by fluid retention in the mediastinum.

Conclusion: Both a safe surgical approach and preventive measures to alleviate postoperative complications are mandatory in difficult cases with thoracic OPLL.