Thoracoscopic anatomy and approaches of the anterior thoracic spine: cadaver study

Abstract

Purpose: [corrected] In spite of the extensive case studies considering thoracoscopic approaches to the anterior thoracic spine, the literature lacks studies of the thoracoscopic anatomic dissection and approaches. In this article, the authors present their study of thoracoscopic anatomy of the anterior spine with illustrated step-wise dissection and approaches for sympathectomy, discectomy and corpectomy.

Materials and methods: Four adult cadavers with no history of disease, local trauma or surgery were studied and bilateral thoracoscopic anterior spinal approaches were performed. Thoracoscopic dissections were done in the Department of Anatomy, using Karl Storz 30°, 5 mm and 30 cm rod lens rigid endoscope (Karl Storz and Co., Tuttlingen, Germany). As surgical instrumentation, Karl Storz Rosenthal endoscopic surgical set and 15 mm portals were used for all approaches.

Results: For sympathectomy, the cadaver is positioned supine and the port locations are in the third and fifth intercostal spaces in the anterior axillary line. The stellate ganglion is cephalad to the second rib, and the T2 and T3 ganglia are divided just superior to T2 ganglia and inferior to T3. For discectomy, the cadaver is positioned in the lateral decubitus position. The working portal is positioned directly over the affected disc in the posterior axillary line. The camera portal is positioned in the middle axillary line; 2-3 intercostal spaces caudal to the working portal. The rib head is removed and the lateral surface of the pedicle and neural foramen are exposed. The pedicle and the floor of the spinal canal are resected to decompress the ventral aspect of the spinal canal. For corpectomy, the position of the cadaver and ports are as same as for discectomy. The adjacent segmental vessels are divided first, and the discs above and below the targeted corpus are removed. The ipsilateral pedicle is then removed to decompress the anterior spinal cord, followed by median corpectomy.

Conclusions: Thoracoscopic approaches are minimally invasive procedures and they can be used safely in patients who need anterior exposure to the thoracic spine for the treatment of a spectrum of diseases. Knowledge of the normal anatomy and thoracoscopic cadaver dissection are essential steps in improving the learning curve.