F racture dislocation of the thoracic spine is a rare spinal injury often re- sulting from high-energy trauma. Associ- ated soft-tissue thoracic injuries are com- mon and are compounded by the often-associated paraplegia. Exceptionally, there are some cases of thoracic spine dis- locations without neurological injuries. 1 A major challenge in the surgical manage- ment of such spinal fractures is achieving reduction and then maintaining it after stabilization. The goals of surgical man- agement of these unstable spine fractures are 4-fold: (1) achieving reduction; (2) immediate stabilization and maintenance of reduction, coupled with spine fusion; (3) decompression of the neurological el- ements (if indicated); and (4) early mobi- lization. 2-4 Classic posterior spinal instrumenta- tion, such as screw-plate, hook-rod and screw-rod systems, has been used suc- cessfully. It has been shown that most of these unstable injuries can be managed using these techniques without the need for additional combined or staged ante- rior spinal surgery. 5,6 However, recent concerns have been raised that mainte- nance of reduction, restored height and sagittal balance has not occurred in long- term follow-up using such systems. 7,8 As for thoracolumbar, unstable burst frac- tures, some have advocated that anterior decompression and anterior column re- constructions must be done to avoid de- layed loss of coronal and sagittal balance, 9 but for fracture dislocations most of the literature has described a posterior ap- proach. 10,11 It has been our experience that the use of side-opening pedicle screws facili- tates reduction to help achieve the surgi- cal goals previously enumerated. Technique The patient is positioned in the standard prone fashion with appropriate bolsters. Care must be taken when rolling the pa- tient. If the surgeon does not have access to a Jackson table, then axial traction (head to feet) should be applied to the pa- tient when log rolling to minimize transla- tions of the spine. A standard midline ap- proach with elevation of paraspinal musculature is taken, exposing the spine out to the transverse processes. Cautious dissection is warranted across the fracture dislocation, so as not to inadvertently in- jure the possibly exposed dural elements. Dissection is done 2 levels above and 2 below the fractured/dislocated segment. Once standard bony landmarks have been identified, we then insert 2 pairs of pedicle screws above and 2 below the dislocation. Anatomical barriers Classically with such fracture dislocation of the thoracic spine, the facet(s) can be jumped, perched or impacted. Manual re- duction of such pathology is often war- ranted. The facet joint can be reduced manually by introducing a large Penfield instrument underneath the inferior facet. Ideally one would prefer to leave the facet in place; however, if the reduction fails, then undertaking superior and/or inferior resection of one or both facet joints may be justified. Despite this, in some rare cases (particularly delayed cases) one may still not be able to reduce the spine. To facilitate the reduction, we place the implants in a special configuration to generate greater reduction force, thus fa- cilitating reduction of the spine to the pre- contoured rod with appropriate sagittal and coronal alignment. The complex re- duction clamp, the “Persuader” from the AO Universal Spine System (USS; Syn- thes, Paoli, Pa.), also facilitates the reduc- tion manoeuvre, because it is able to bring the spine to the rod simultaneously in 2 different planes (Fig. 1). Sagittal reduction To facilitate our spinal reduction in the sagittal plane, we purposely leave the screws slightly proud (from 5 mm to 10 mm according to the amount of dislo- cation/displacement and the anticipated difficulty in reduction) on the segment that is posteriorly translated (usually dis- tal). On the other hand, we insert the screws flush to the spinal elements in the segment that is anteriorly translated (usu- ally proximal). We purposely create an ex- aggerated offset of the pedicle screw height of 5–10 mm. By doing so, we Accepted for publication June 13, 2005 Correspondence to: Dr. Vincent Arlet, 400 Ray Hunt Dr., Suite 330, Department of Orthopaedic Surgery, Division of Spine Surgery, University of Virginia, Charlottesville VA 22903; va3e@hscmail.mcc.virginia.edu Continuing Medical Education Formation médicale continue Surgical technique Technical notes on reduction of thoracic spine fracture dislocation Abdulrazzaq Alobaid, MD;* Vincent Arlet, MD; † Jean Ouellet, MD;* Rudolph Reindl, MD* From *McGill University Health Centre, Montréal, Que., and the †Spine Unit, University of Virginia, Charlottesville, Va. © 2006 CMA Media Inc. Can J Surg, Vol. 49, No. 2, April 2006 131