Giant central thoracic disc herniations: surgical outcome in 17 consecutive patients treated by mini-thoracotomy.

Purpose: Safe treatment of giant central thoracic disc herniations (cTDHs) remains a surgical challenge due to frequent calcifications, intradural extension and, importantly, the rare exposure of spine surgeons to these lesions. We report our 10-year experience in the management of giant cTDH by mini-thoracotomy and offer a detailed description of the technique.

Methods: 17 patients harboring 17 giant cTDH operated on via a mini-thoracotomy at the authors' institution between 2004 and 2014 were reviewed. All patients presented with myelopathy of varying magnitude. Mean patient age was 47 years. The mean follow-up period was 5.5 years. Median canal compromise of the cTDH was 66 %. cTDH were densely calcified in 7 (41 %), partially calcified in 6 (35 %) and soft in 4 (24 %) patients. Intradural extension of cTDH was noted in six patients (35 %). Benzels' modified myelopathy score of the Japanese Orthopedic Association was adjusted for the evaluation of thoracic myelopathy (mJOA) to assess functional outcomes.

Results: Successful removal of the offending cTDH was achieved in all patients. The overall mJOA Score improved from 7.9/13 to 11.1/13. Two patients with giant and densely calcified cTDH experienced a transient post-operative neurological decline. There was a statistically significant correlation between size of cTDH and intradural extension.

Conclusion: Patients with myelopathy due to giant cTDH can be safely treated by the mini-thoracotomy approach. Postoperative neurological worsening and severe complications or incisional pain are rare. In contrast to complex posterior or thoracoscopic approaches, the mini-thoracotomy is technically straightforward and thus easy to learn for experienced spine surgeons.