Abstract

Techniques for minimally invasive spine surgery (MISS) have only been widely used in the past decade. Currently, the most commonly used MISS procedure in children is video assisted thoracic surgery (VATS). We have had extensive experience using VATS for anterior release and fusion for scoliosis and kyphosis. Scheuermann’s kyphosis continues to be an indication for anterior release and bone grafting, which achieves a much better correction of the kyphosis and, indirectly, the compensatory lumbar lordosis. VATS with instrumentation can be used for correction of thoracic curves in patients with idiopathic scoliosis. In addition, VATS has been useful in conjunction with posterior spine fusion for severe scoliosis (>90 degrees). However, with more extensive use of pedicle screw fixation to achieve curve correction, many surgeons have returned to a posterior approach alone for scoliosis correction. Indeed, correction of thoracic scoliosis with anterior instrumentation has limited indications, including moderate curve size and flexibility. Positioning of the instrumentation is critical as the screws can be close to vital structures, particularly the aorta. Further, the anterior placement of dual rods to increase construct stiffness during fusion is technically challenging. These drawbacks have dampened initial enthusiasm for the procedure. VATS has also been used to insert various implants for guided growth of the spine. By slowing unilateral growth, these implants can gradually correct curvature of the spine in the growing child. Several spine centers have been working on a number of promising techniques to gradually correct scoliosis in children. VATS can be helpful for the treatment of congenital scoliosis, both for hemiepiphyseodesis and removal of hemivertebra with a combined anterior/posterior approach. There has been limited application of MISS in children with spine tumors, such as removal of osteoid osteoma. However, MISS has been particularly helpful for tumor biopsies. In the treatment of osteomyelitis, MISS has been used for biopsy and drainage of abscesses, especially for tuberculosis. It has not been widely used for anterior stabilization of spine fractures in children. However, it does have application for short segment posterior fusion of 1-4 levels, such as in the direct repair of a spondylolysis or fracture stabilization. There are limitations to the use of MISS in children, primarily because of complications associated with anesthesia and ventilation of one lung. Prone positioning can help minimize the need for single lung ventilation, and allows for proceeding to posterior spine fusion when necessary. Previously, small children under 20 kg were considered poor candidates for VATS, but recent advances have allowed limited use in this population. This technique is still in its infancy and there is still a steep learning curve; many of the applications are experimental. Indications for use of MISS for deformity correction are being explored. In the future, as better equipment becomes available, particularly for guided growth and gradual correction of scoliosis in the young child, MISS is likely to gain popularity.