Anatomic considerations of pedicle screw placement in the thoracic spine. Roy-Camille technique versus open-lamina technique.

Abstract

In this cadaveric study, the outcomes of two techniques for pedicle screw placement in the thoracic spine were compared. To assess the Roy-Camille technique, and to determine whether pedicle screw placement, aided by partial laminectomy, could decrease the incidence of pedicle violations. Pedicle screw fixation in the thoracic spine remains technically challenging. The Roy-Camille method may be one of the leading techniques of thoracic pedicle screw placement. However, there are few studies evaluating this technique and determining methods to decrease the incidence of thoracic pedicle penetration with screw insertion. Ten cadaveric thoracic spines from T1 to T10 were used for pedicle screw placement. Two techniques of transpedicular screw placement were used, the Roy-Camille technique (screw placed on the right side; used in 95 screw placements) and the open-lamina technique screw placement with combined partial laminectomy (screw placed on the left side; used in 94 screw placements). After screw placement, all specimens were evaluated visually to determine violation of the pedicle. The screw placement with the Roy-Camille technique had a higher percentage of pedicle violation (54.7%) than did that with the open-lamina technique (15.9%). No Grade III violation was seen in the screw placement with the open-lamina technique. The Roy-Camille technique was associated with a high incidence of pedicle violation, whereas screw placement with a partial laminectomy significantly reduced the incidence of pedicle violation. Pedicle screw fixation in the thoracic spine remains a technical challenge and should not be used routinely. Screw placement with the open-lamina technique is recommended if pedicle screw fixation is strongly indicated in the thoracic spine.