Anterior surgery results in the most effective decompression of the spinal canal after burst fracture. Anterior surgery is indicated in patients with thoracolumbar fractures with an incomplete spinal cord injury
It is generally not indicated in patients without a neurologic deficit except in cases of patients with very severe kyphosis.
Supplementary posterior fixation is added in cases with massive posterior ligamentous disruption.
Anterior surgery is usually deferred in cases of retroperitoneal or intrathoracic injuries.
The patient is placed in the lateral position with the left side up on a standard operating table. The preparation and draping of the skin should include the iliac crest.
The intercostal approach interval should be one to two levels above the level of the fracture. For example, for approaching D9 vertebra, D7 intercostal interval is preferred.
In the next step, the segmental vessels at the injured and adjacent levels are ligated at the midvertebral body level. It is important to ligate them at this level to preserve the arterial anastomotic branches that supply the artery of Adamkiewicz.
The borders of the disc spaces above and below the fracture are then delineated via subperiosteal [Under the periosteum, periosteum is a layer that covers the bone] dissection.
After complete discectomy, the majority of fractured bone is removed with a rongeurs. This bone can be saved for subsequent grafting.A shell of anterior and lateral vertebral body is left to potentiate blood supply to the interbody graft. Finally, the posterior vertebral body fragments are removed with straight and angled curettes.
A rod-screw-staple construct, such as the Kaneda device is preferred choice of instrumentation for anterior fixation.
In this, the staple is tamped into place along the midlateral aspect of the vertebral body. The posterior holes should lie over the posterior aspect of the vertebral body.
Next, drill holes are made and screws are fixed.
The posterior screws are placed parallel to the posterior vertebral body but the anterior screws are angled slightly posteriorly.
After the screws are put, a distractor if required is used for final alignment and kyphotic correction.
After the instrumentation, the bed is prepared for bone grafting. Material for bone graft is taken from iliac crest and can be mixed with the bone from removed vertebral bone. Sometimes allograft [Harvested bones from other people who have donated bones] is also used as bone graft.
With gentle overdistraction applied through the screw-staple device, the cage or bone is tamped into place.
It should be centered along the endplates of the cranial and caudal vertebrae. Once the strut is in place, the distractor is removed.
Rods are then cut to the appropriate length and inserted into the screw holes. A single cross-connector is then applied to increase the torsional rigidity of the construct.
If the fixation is good, postoperative bracing is usually not necessary.
The wound is closed in layers. A chest tube is inserted for drainage while closure.
The patient should be mobilized as needed.
The chest tube is removed once drainage has diminished, and a follow-up chest x-ray is obtained to rule out pneumothorax. The stitches are removed after 12-14 days.