Surgical Management of Posttraumatic Thoracolumbar Kyphosis
The authors reviewed available literature regarding current treatment methods for posttraumatic thoracolumbar deformity. In the United States alone, 10,000 to 17,000 people will have a spinal cord injury annually. Those that fracture their spine exceed 150,000 annually. As a result of improved medical care, more people are surviving these injuries. Disruption of the vertebral column and supporting ligamentous structures can result in posttraumatic spinal deformity. As a result, kyphosis, stenosis, instability, and scoliosis are becoming more common.
The most common late complaints following spinal injury include deformity such as kyphosis, increasing pain, and increasing neurologic deficits. New or increasing neurological deficits can be caused from increasing deformity, or from the development of posttraumatic syringomyelia. Twenty one to 28 percent of persons with spinal cord injury will develop a syrinx. Posttraumatic syringomyelia usually is identified by segmental pain, sensory loss, and progressive asymmetrical weakness. Kyphosis equal to or greater than 30 degrees increases risk for chronic pain and potential for neurological compromise. The authors feel that studies suggest that restoration or maintenance of normal spinal anatomy can prevent the development of posttraumatic syringomyelia and secondary neurological deficits.
Surgery to treat posttraumatic deformity is considered when there is axial back pain, pseudarthrosis or malunion, breakdown of levels above or below the original injury site, radiculopathy or increasing neurological deficit. When considering surgery, assessment of the degree of focal deformity is important. It is well known that a kyphosis deformity of 30 degrees or greater has an increased risk of chronic pain or progressive deformity. The authors note that half of patients treated with short fusion segments will eventually have progressive kyphosis.
Pseudoarthrosis that leads to instability will most likely benefit from combined anterior and posterior revision. Another option is a posterior approach with anterior interbody fusion. These procedures have shown to increase the chances of successful union. The authors suggest that anterior column support should be considered if fusion is extended to the sacrum due to high pseudoarthrosis rate otherwise.
Stiff or inflexible posttraumatic deformities are more difficult to correct and often require an osteotomy. There are several types of osteotomies that can be performed.
Results of surgical treatment of posttraumatic deformity are generally encouraging. Results are dependent on the type of initial injury, the time between the injury and the treatment of posttraumatic deformity, age, and medical condition of the patient. Surgical options include anterior approach, posterior approach, and a combined anterior and posterior approach. Regardless of the approach, the authors emphasize that thorough decompression of the neural elements is essential, as well as correction of the deformity.
While many patients have improved neurological function following surgery, up to 20 percent of patients may have worsening of neurological function. This risk can be decreased with spinal cord monitoring during surgery. Postoperative infection is also a potential complication of surgery.
J. M. Buchowski et al. Surgical management of posttraumatic thoracolumbar kyphosis.SPINE July 2008. Voume 8. Number 4. Pp. 666-677.