Cervicothoracic junction kyphosis: surgical reconstruction with pedicle subtraction osteotomy and Smith-Petersen osteotomy
Presented at the 2009 Joint Spine Section Meeting
Srinath Samudrala, Shoshanna Vaynman, Ty Thiayananthan, Samer Ghostine, Darren L. Bergey, Neel Anand, Robert S. Pashman and J. Patrick Johnson
Sagittal plane deformities can be subdivided into kyphotic and lordotic forms and further characterized according to their global or regional (focal) presentation. Regional deformities of a significant magnitude constitute a gibbous deformity. Pedicle subtraction osteotomy (PSO) and interlaminar Smith-Petersen osteotomies have been used to correct sagittal plane deformities in the cervical, thoracic, and lumbar spine. By resecting a portion of the vertebral body and closing in the gap of this vertebra, the spine is placed in local lordosis and kyphosis is corrected. These osteotomies have generally been carried out in the lumbar or less frequently in the thoracic area. While PSO has been performed in the mid and lower thoracic spine, there have been no case series of patients undergoing PSO at the CTJ. Specifically, a PSO approach that addresses the challenges of the CTJ is needed. Here, the authors review their case series of PSOs performed in the CTJ. Their goal in the treatment of these patients was to correct the regional CTJ kyphosis, restore forward gaze, and reduce the pain associated with the deformity.
Eight patients (5 males and 3 females, mean age 63 years) underwent PSO for the correction of CTJ kyphosis. Pedicle subtraction osteotomy was performed at C-7 or the upper thoracic vertebrae and was facilitated by a computer-guided intraoperative monitoring system. Surgical indications included postlaminectomy kyphosis, spinal cord tumor resection, posttraumatic kyphosis, and degenerative cervical spondylosis.
The mean follow-up was 15.3 months (range 12–20 months), and the mean preoperative CTJ kyphosis was 38.67° (range 25°–60°). Clinically satisfactory correction of the regional deformity was accomplished in all patients, achieving a mean correction of 35.63° (range 15°–66°) at the CTJ, with restoration of forward gaze and significant reduction in pain.
A CTJ deformity is a distinctive form of kyphosis that presents as a variable local deformity and requires complex spinal reconstructive techniques to restore sagittal balance and forward gaze. Pedicle subtraction osteotomy allows for significant correction through one spinal segment, and it can be used safely to correct the regional sagittal alignment of the cervical spine and head in relation to the pelvis. Pedicle subtraction osteotomy can be used alone or in combination with other techniques as some patients may require multistage procedures with anterior and posterior spinal reconstruction to obtain stable sagittal correction. All deformities in these patients were kyphotic in nature with only mild elements of scoliosis or coronal plane deformity. This is unlike lumbar and thoracic curves where the kyphosis is frequently associated with scoliosis.
J. Patrick Johnson, Robert S. Pashman, Carl Lauryssen, Neel Anand, John J. Regan and Robert S. Bray
✓ Spinal deformity has classically and historically been studied by those in the discipline of orthopedic surgery. This may be attributable to the orthopedic interventionalists' experience with osseous fixation for long-bone and other skeletal fractures. Neurosurgeons have maintained a long-standing interest in complex cervical spinal disorders, and their interest in the larger field of complex spinal deformity has been expanding.
An understanding of spinal deformity disorders, biomechanics, bone biology, and metallurgy is necessary before clinical, teaching, and research activities can be undertaken within neurosurgery.
The authors describe basic and advanced concepts of spinal deformity management with cases to illustrate teaching points.
J. Patrick Johnson, Carl Lauryssen, Helen O. Cambron, Robert Pashman, John J. Regan, Neel Anand and Robert Bray
The authors evaluated cervical spine radiographs to determine sagittal alignment in patients who underwent one- or two-level arthroplasty with the Bryan cervical artificial disc prosthesis.
The curvature of the surgically treated spinal segments and the overall curvature of the cervical spine were evaluated in 13 patients who underwent 16 cervical arthroplasty device placements. Preoperative and postoperative lateral radiographs were reviewed and compared using standardized techniques for measuring spinal curvature. Patients who underwent a single-level cervical arthroplasty had a 4.7° mean reduction (p < 0.05) in lordosis after cervical artificial disc replacement. The three patients who underwent two-level cervical arthroplasty had no significant changes in the sagittal alignment.
Patients who underwent arthroplasty with a Bryan cervical artificial disc had a focal loss of lordosis (that is, kyphosis) at the treated levels after single-level procedures. Nevertheless, there was no significant change in the overall sagittal curvature of the cervical spine after single-level artificial disc replacements. The patients who underwent two-level artificial disc placement had no significant changes in lordosis at the treated levels or in the overall curvature. The likely source of this outcome appears to be the endplate milling procedures that reorient the vertebral endplates.