A Case of Intradural Thoracic Disc Herniation: Technical Report

Objective: The aim of this report is to describe the rare case of a thoracic intradural disc herniation with provided detailed video and imaging illustrations of the surgical procedure.

Background: Intradural disc herniations (IDH) are rare, comprising from 0.2 to 2.2% of all herniated discs.¹ The most frequent localization is the lumbar region (92%), followed by the thoracic (5%) and lastly the cervical one (3%).² The radiologic preoperative diagnosis of the intradural component by magnetic resonance imaging (MRI) or computed tomography scan myelogram is difficult and it is, therefore, often identified intraoperatively. Here, we describe a case of intradural thoracic disc herniation.

Case Report: We report on the case of a 49-year-old female, who had undergone elsewhere to incomplete removal of two thoracic disc herniations at Th7-Th8 and Th8-Th9 levels. At an 8-month follow-up, the patient complained of persistent left thoracic pain, mild-to-severe paraparesis with normal bladder and bowel function. The MRI revealed persistence of a calcified median and paramedian Th8-Th9 disc herniation with compression and displacement of the thoracic cord. Patient was operated on through a left side thoracotomy under neuromonitoring. During surgery, the calcified disc was dissected and drilled away from the dura mater. An intradural component was identified and resected. The cerebrospinal fluid leakage was managed by combined local application of Tachosil and Tisseel. Patient was left for 2 days and then early mobilization was started. Immediate relief of the thoracic and leg pain was reported after the operation, and the patient was sent to rehabilitation center.

Conclusion: In conclusion, establishing the diagnosis of IDH prior to surgery is difficult, especially in patients with previous interventions at the same level. Physicians should be aware of this rare type of disc herniation to provide the best therapeutic approach.