Transforaminal Endoscopic Thoracic Discectomy: Technical Review to Prevent Complications

Abstract

For all the spine surgeons, thoracic disc herniations (TDHs) entrust a real challenge in terms of patient diagnosis, proper selection, surgical technique, and potential adverse events. TDHs are relatively uncommon compared to the lumbar and cervical levels. Literature reports a variable prevalence of TDHs around 6% to 40%, but less than 1% of all disk herniations are symptomatic TDHs, evidencing as a relatively unusual condition. Nowadays, transforaminal endoscopic thoracic discectomy (TETD) has been implemented as an alternative to classic open procedures with results that are as good as and, in some situations, better than those in traditional discectomy. However, the surgeon must be familiar with endoscopic lumbar spine surgery before opting to perform a TETD, considering that the learning curve is much harder. We describe all the steps and safety considerations during TETD based on the anatomic differences compared to lumbar endoscopic procedures. TETD is an effective and safe method that yields more benefits, provides a direct route to the lesion with less morbidity, and is performed in a minimally invasive way. Many severe complications related to the thoracic region could be avoided having the proper knowledge, adequate technique, and safety routes and considerations.

Full endoscopic surgery for thoracic pathology: an assessment of supportive evidence

“…Heat injury from use of laser or radiofrequency might be a concern for the surgeon due to the anatomy of the thoracic canal, with a higher density of the spinal cord compared to the multiple roots in the lumbar region. 68 Although there is less CSF to buffer against heat, full endoscopy is performed under continuous irrigation mitigating this risk. It is interesting to note that, with respect to the open approaches, the lateral and posterolateral approaches had lower overall complications than the anterior approaches (although the latter were reduced with thoracoscopy), but were more liable to inadequate decompression.…”

Full Endoscopic Surgery for Thoracic Pathology: Next Step after Mastering Lumbar and Cervical Endoscopic Spine Surgery?

“…Paramedian soft herniation with pain is the best indication for them. With experienced hands, challenging cases like myelopathy or calcified disc can be safely performed [ 1 , 2 , 11 – 13 ]. Concomitant ossification of the posterior longitudinal ligament or spinal infection is excluded.…”

“…The basic concept for the transforaminal or interlaminar approach is similar to the lumbar spine [ 8 – 10 ]. Endoscopic approaches to the thoracic spine have been reported and found to be safe and effective as well as avoiding approach-related complications with injury to the visceral and vascular structure [ 1 , 2 , 11 – 13 ].…”

Expanded Indications of Full Endoscopic Spine Sugery

“…(3) Thoracic FESS Most authors have reported good outcomes on their FESS approaches in the thoracic spine. In one of the largest series reported by Bae et al on 92 patients undergoing full endoscopic surgery of the thoracic spine, they reported excellent or good outcomes(Modified Macnab's criteria) in 90% patients 159) . Complications were reported in 6.5% patients out of which 2 had recurrent disc herniation.…”

“…It is worthwhile to note that these extended indications once formed contraindications to endoscopy. Generally, patients with profound neurological deficits due to significant myelopathy, history of previous spine surgery and multi-level involvement are few contraindications for this type of surgery 159) . TETD though has been recently contraindicated in patients with severe acute or progressive myelopathy due to hard or calcified disc herniation, OPLL and severe disk narrowing, Costotransverse joint needs to be drilled to widen the access in most of the cases 160) .…”