Thoracic Endoscopic Discectomy (TETD)

The thoracic spine is the long middle section of the back, to which the ribs attach. Disc herniations here are much less common than in the neck or lower back, but they can be serious: because the spinal canal is narrow and the cord sits directly behind the disc, a herniation can press on the cord itself, causing thoracic myelopathy — problems with walking, balance, and sometimes bladder function — as well as a band of pain around the chest or trunk. Many of these discs are also calcified, hardened almost to bone, which makes them especially challenging to remove. Deciding which thoracic discs genuinely need surgery is itself an important judgement, because the cord must never be manipulated.

This is where the endoscopic technique earns its place most dramatically. The traditional operations for a thoracic disc are big: a thoracotomy, opening the chest to reach the disc from the front, or a costotransversectomy, removing part of a rib and the bony processes to reach it from the side and behind. These work, but they are substantial operations with significant recovery. The transforaminal endoscopic approach reaches the disc from the side, through a corridor a few millimetres wide, and — crucially — works on the front of the canal from an angle that lets me remove the disc away from the cord rather than towards it. The cord is never retracted. For a problem defined by the danger of touching the cord, an approach that removes the disc from the safe side, through a keyhole, is a genuine step forward.

Under x-ray and often awake monitoring, the working sleeve and endoscope are docked at the thoracic foramen and a controlled foraminoplasty opens the way to the front of the canal. The herniated disc is then removed under continuous irrigation and magnified vision, working ventrally — in front of the cord — and drawing the fragment down and away from the neural structures. Where the disc is calcified, the approach becomes a careful bone-working task: the hardened disc is thinned and taken down with fine burrs and instruments, a little at a time, until the cord is decompressed. This is painstaking, deliberate work, and I am candid that a calcified thoracic disc is among the most demanding operations I perform.

I want to be especially clear here, because thoracic disc surgery is high-stakes work that must be approached with great caution and precise patient selection. The margin for error next to the thoracic cord is minimal; the decompression must be complete, the cord must never be pressured, and the approach must be planned meticulously from CT and MRI. Not every thoracic disc is suited to an endoscopic approach — some, by their size, position or calcification, are better managed by other means, and making that judgement honestly is as much a part of the expertise as the technique itself. This is precisely the kind of frontier surgery that subspecialisation in endoscopic technique exists for, applied selectively and carefully.

The evidence for endoscopic thoracic discectomy is encouraging and growing. A systematic review and meta-analysis of full-endoscopic thoracic discectomy reported low rates of the feared complications — dural tears around one percent and worsening myelopathy around two percent — supporting its safety in experienced hands. Comparative studies against open surgery show equivalent short-term neurological recovery with markedly less blood loss, shorter hospital stays and lower cost, and long-term series report durable relief at five years, including for calcified and large discs. Technical reviews emphasise, as I do, that the whole point of the approach is to decompress the cord ventrally without manipulating it. The literature honestly reflects that this is a demanding technique with a real learning curve.

Because the operation avoids opening the chest and spares the muscles, recovery is generally far quicker and more comfortable than the traditional alternatives — often a short hospital stay and a graded return to activity, rather than the longer recovery of a thoracotomy. Where the surgery is for myelopathy, improvement in walking and balance can be gradual, and the aim is often to halt progression and allow recovery over time. Because this is advanced surgery, the plan is always individualised after a thorough assessment, and the spine is followed up carefully over the longer term.

• —Silva JDS, et al. Full-endoscopic discectomy for thoracic disc herniations: single-arm meta-analysis of safety and efficacy. (PMID 36867252)
• —Endoscopic versus traditional thoracic discectomy: multicenter retrospective case series and meta-analysis. (PMID 38899868)
• —Open versus endoscopic approach for thoracic disc herniations: equivalent outcomes, different costs. (PMID 39189741)
• —Five-year outcomes after transforaminal endoscopic foraminotomy and discectomy for soft and calcified thoracic disc herniations. (PMID 33963033 / PMC8176827)
• —Transforaminal endoscopic discectomy for large, two-level calcified thoracic disc herniations: 5-year follow-up. (PMID 33401876)
• —Gao S, et al. Full-endoscopic transforaminal ventral decompression for symptomatic thoracic disc herniation with or without calcification. (PMC8580684)
• —Transforaminal endoscopic thoracic discectomy: technical review to prevent complications. (PMC7410381)