A Modified Posterior Transdural Approach for Soft and Calcified Thoracic Disc Herniations: A Technical Note

Thoracic disc herniation (TDH) is a rare condition that often presents with myelopathy and lower extremity weakness. Surgical management is particularly challenging in calcified herniations because of the vulnerability of the spinal cord and the potential risks associated with standard transdural or transthoracic approaches. This technical note describes, in a step-by-step manner, a modified posterior transdural approach (PTA) for the removal of calcified TDHs, with the aim of reducing intraoperative complications, particularly those related to spinal cord exposure. A modified PTA for the removal of both soft and calcified TDHs is described. The procedure begins with laminectomy and resection of the ipsilateral caudal pedicle and transverse process. A small posterior midline dural opening is then created, with cerebrospinal fluid (CSF) drainage performed to relieve intradural tension, analogous to a deflated balloon. This maneuver allows careful mobilization of the herniated fragments without applying traction to the spinal cord. The anterior dura is left intact, substantially reducing the risk of CSF fistula after anterior disc dissection. Intraoperative neurophysiological monitoring (IONM) is mandatory. This approach allowed safe decompression and removal of a partially calcified TDH while protecting the dural sac. IONM remained stable. Complete spinal cord decompression was achieved, with postoperative neurological improvement. This technique allows safe removal of soft and calcified TDHs while protecting the spinal cord, minimizing direct manipulation, and reducing the risk of postoperative CSF fistula. Compared with transthoracic approaches, it may also reduce pulmonary and overall surgical risks.