The thoracic spine may be approached by different ways: posterior, posterolateral, anterolateral and anteriorly, with associated removal of diverse osseous structures as facet joints, costal processes, pedicles and ribs, subsequently imposing the use of diverse fusion procedures in some cases. The extreme lateral approach to the thoracic disc space produces minimum disruption of the normal spinal musculoskeletal anatomy, avoids retraction of the spinal cord and preserves the intercostal neurovascular bundle and the segmental radicular arteries. The operation is carried out with the patient in the prone position, and the patient is rotated away from the surgeon as necessary when the deeper levels are accessed. Radioscopy is used to identify the correct level after positioning of the patient A straight transversal paravertebral incision is recommended in single-level operations. Alternatively an elliptical incision, concave medially and centered at the marked rib, is done and the skin flap is refleted medially. The muscles are partially divided at rigth angles over the rib to be excised and refleted cranial and caudally, exposing the rib and transverse process. The target disc is approached by removal of about 5 cm of the rib which has its insertion at the disc level, if necessary associated with partial removal of the transverse process, followed by partial pediculotomy (exclusively at the base of the pedicle) and a little lateral rachotomy (vertebral body ressection), which permits opening of the spinal canal exclusively ventral to the intervertebral foramen. In this way any kind of hemilaminectomy or facectomy is avoided. The discectomy is then carried out. This is a minimally invasive approach in comparison to the current ones. As the facet joint is preserved and the pedicle just partially removed, a fusion procedure is not necessary. This technique has potentially important consequences for long term spinal stability after multilevel operations. The initial results of nine patients are promising. In this little series up to four disc herniations in the same patient were operated at the same occasion.
thoracic vertebrae; intervertebral disk; spinal diseases; operative technique