Endoscopic surgery on the thoracolumbar junction of the spine

Abstract

The thoracolumbar junction is the section of the truncal spine most often affected by injuries. Acute instability with structural damage to the anterior load-bearing spinal column and post-traumatic deformity represents the most frequent indications for surgery. In the past few years, endoscopic techniques for these indications have partially superseded the open procedures, which are associated with high access morbidity. The particular position of this section of the spine, which lies in the transition area between the thoracic and abdominal cavities, makes it necessary in most cases to partially detach the diaphragm endoscopically in order to expose the surgical site, and this also provides access to the retroperitoneal section of the thoracolumbar junction. A now standardised operating technique, instruments and implants specially developed for the endoscopic procedure, from angle stable plate and screw implants to endoscopically implantable vertebral body replacements, have gradually opened up the entire spectrum of anterior spine surgery to endoscopic techniques.

Fig. 1

Standard set up for endoscopic spine surgery. The patient is placed in a true lateral position; four portals are positioned

Fig. 2

OR—set-up and instruments

Fig. 3

Placement of the trocars at the thoracolumbar junction

Fig. 4

View at the diaphragm from below, showing the diaphragm and the anatomical conditions at the thoracolumbar junction. The course of the incision (black interrupted line) runs parallel to the attachment of the diaphragm

Fig. 5

Endoscopic view at the thoracolumbar junction from above. The course of the incision at the attachment of the diaphragm is marked

Fig. 6

K-wire insertion, exposure and dissection of the segmental vessels

Fig. 7

Insertion of the tricortical bone graft into the partial corpectomy defect. Dissection of the retropulsed fragment under direct visualisation of the dura. Removal of the fragment

Fig. 8

The anterior reconstruction including bone graft insertion and instrumentation is completed

Fig. 9

Resection of the pedicle in order to expose the lateral dural sac

Fig. 10

Resection of parts of the postero-lateral aspect of the vertebral body under endoscopic view at the dura

Fig. 11

The decompression of the spinal canal is completed

Fig. 12

Endoscopic anterior release using a sharp osteotome at the intervertebral disc T12/L1. A blunt and slightly curved cobb raspatory is placed in front of the intervertebral disc to protect the aorta

Fig. 13

Screw loosening after anterior instrumentation. The screw migrates towards the spleen

Fig. 14

Endoscopic detachment of the diaphragm and exposure of the spleen and screw

Fig. 15

Removal of the screws

Fig. 16

Ostoperative radiological and clinical result demonstrating the different aesthetical aspects after open and endoscopic approach

Fig. 17

Case report: 18-year-old female after car accident, compression/rotation fissured fracture type C 1.3.2 (AO classification)

Fig. 18

Transversal CT layer and two-dimensional and three-dimensional reconstruction of the injury

Fig. 19

Postoperative X-ray check after initial dorsal bisegmental stabilisation and subsequent thoracoscopic monosegmental ventral fusion with the MACS TL system Th 11-12

Fig. 20

Transversal CT layers showing the bicortical screw fixation of the caudal section of Th 12, position check of tricortical iliac crest graft and two-dimensional reconstruction to check position after monosegmental stabilisation Th 11-12

Fig. 21

Clinical and cosmetic result after suture removal 10 days post-op

Fig. 22

Case example of a burst fracture L1(type A 3.3) with incomplete neurological deficit (ASIA C) and severe canal compromise. Preoperative X-rays and CT scans

Fig. 23

Postoperative CT scans for the assessment of spinal canal clearance after having performed dorsal reduction and fixation

Fig. 24

Postoperative X-rays and CT reconstructions

Fig. 25

Lateral X-ray view showing the relation of a bisegmental anterior instrumentation T12–L2 to the diaphragm

Fig. 26

Post-traumatic kyphosis and instability after initial dorsal reduction and stabilisation of a L1-fracture followed by infection and early implant removal

Fig. 27

Postoperative result after dorso-ventral osteotomy and dorso-ventral-dorsale instrumentation

Fig. 28

Correction of post-traumatic kyphosis: preoperative and postoperative result and mean loss of correction in a 1-year period

Fig. 29

Preoperative and postoperative status of the patients according to the VAS-scale