Thoracoscopic Spine Surgery

Introduction
Spine surgery is rapidly evolving and new techniques including thoracoscopic surgery have the potential to decrease post-operative pain and lead to a faster return to normal function. Video-assisted thoracoscopic surgery (VATS) was first introduced some 80 years ago, but has only been in regular use for twenty years. While it seems clear that thoracoscopic spine surgery will clearly have a role in modern day scoliosis surgery, guidelines regarding appropriate indications continue to evolve.

What is Thoracoscopic Spine Surgery?
The thoracoscopic approach allows the surgeon access to the anterior thoracic spine without the large incision or chest wall musculature dissection used in the open approach. Multiple small skin incisions are made along the side of the chest wall to allow insertion of a fiber-optic camera and surgical instruments. The camera magnifies and allows excellent visualization. The instruments are different from those used in open surgeries, as they reach across the pleural (lung) space towards the spine. Through this approach, vertebral disks are removed, bone-graft added for spinal fusion and instrumentation (screws and rods) may be placed.

Who can have Thoracoscopic Spine Surgery?
The most straightforward use of thoracoscopic surgery involves an isolated anterior release followed by posterior instrumentation. Most people who require release of the anterior thoracic spine can have it done thoracoscopically, though as always, there are some contraindications. (See Below). Anterior release is typically indicated in severe or rigid scoliosis and kyphosis.1, 4 Removal of anterior vertebral disks and anterior spinal ligaments increases the flexibility of the spine and allows for better correction of the curve. Anterior release and fusion is also indicated in young patients who have much growth left, and are at risk for developing a post-operative crankshaft deformity. This phenomenon results from continued growth of the anterior spine, after the posterior spine has been fused, and is characterized by rotational deformity of the spine. Destruction of the anterior growth plates prevents this from happening.

Indications for thoracoscopic instrumentation include Type III curves, which is a single thoracic curve with little or no lumbar curvature. Curves that are hypokyphotic, relatively supple and present in young patients are suitable for thoracoscopic instrumentation.

What are the advantages for Thoracoscopic Surgery over the open approach?
Multiple studies have shown short term efficacy and safety of thoracoscopic anterior release and fusion.1, 4, 6-8, 18, 19 McAfee et al report 100 endoscopic cases without permanent iatrogenic neurologic injuries or deep spinal infections.6 A meta-analysis performed by Arlet on 10 articles consisting of 151 cases indicate successful use of thoracoscopy in anterior discectomies and fusions.18 Picetti and Bueff followed 50 patients undergoing endoscopic instrumentation for a minimum of 2 years and found a curve correction comparable to that of the open approach.17 Initially, operating time was prolonged with thoracoscopy, but as the procedure became more familiar, operating time decreased.1, 17 Betz et al. report a prospective case-control study with 30 patients in each group, with preliminary results indicating that thoracoscopic instrumentation is comparable to open instrumentation in terms of early radiographic results.15 Follow-up time for studies on endoscopic anterior instrumentation is limited to a few years.

One of the major benefits of thoracoscopic surgery is sparing of the chest wall muscles. This is associated with decreased postoperative pain, improved cosmesis and a faster return to normal function.2, 5 Smaller skin incisions result in improved cosmetic results and a theoretical decreased risk for wound infection. Theoretically, this less invasive approach should result in a shorter stay in the hospital and less pain.

Conclusion
Thoracoscopic anterior spinal surgery is a relatively new treatment. However, thoracoscopic surgery promises an easier recovery than traditional scoliosis surgery for certain patients. Consult a specialist with experience with this technique for more information.