Transforaminal endoscopic thoracic discectomy with foraminoplasty for the treatment of thoracic disc herniation.

Background: Symptomatic thoracic disc herniation (TDH) is a rare clinical entity and surgical intervention for it is even more uncommon. Despite several surgical techniques being described for thoracic discectomy, considering the unique surgical challenges, none of them have been accepted universally. Minimally invasive techniques have brought in a paradigm shift in the management of cervical/lumbar spinal disorders and similar techniques have been extrapolated to the thoracic region too. The purpose of this paper is to describe our technique, surgical experience, and the clinical results of transforaminal endoscopic thoracic discectomy (TETD).

Methods: Consecutive patients who underwent TETD (2001-2018) were reviewed. Patients who had a minimum of 6 months of follow-up, and without cervical and lumbar spine surgery or trauma during the follow-up period were included in the study. TETD was performed in patients who presented with symptomatic disc herniation of the thoracic spine and did not respond to conservative treatments. Patients with calcified disc herniation or concomitant ossification of the posterior longitudinal ligament (OPLL) were excluded. Under local anesthesia and intravenous sedation, a 4.7-mm endoscope (TESSYS, Joimax GmbH, Germany) was introduced via transforaminal approach with foraminoplasty using reamer. Patient outcome was evaluated using visual analogue scale (VAS) and Oswestry disability index (ODI) scores. Patient satisfaction was measured using Macnab's criteria.

Results: Ninety-two consecutive patients (mean age was 48.9 years, 57 males) who underwent TETD from 2001 to 2018 met the inclusion criteria. Patients underwent surgery at different levels: 16 patients for T2-3 to T5-6 level, 41 cases for T6-7 to T8-9, and 35 patients for T9-10 to T12-L1. During follow-up for an average of 38.4 months, all patients showed a significant improvement of pain (7.6 to 1.6 in VAS and 68.2 13.2 for ODI, P<0.05 for both). There was one patient who had transient motor weakness.

Conclusions: TETD for soft, paramedian or lateral symptomatic TDH is a feasible and effective minimally invasive treatment option with favorable clinical results.