[Simultaneous thoracoscopically assisted anterior release in prone position and posterior scoliosis correction : What are the limits?].

Background: In spite of modern pedicle-based systems, the correction of a rigid rib hump or hypokyphosis remains a problem in posterior-only scoliosis surgery. As there has so far been no reliable method of predicting the intraoperative extent of kyphosis restoration or rib hump correction by posterior-only surgery, it has been difficult to determine the indication for an additional anterior release.

Methods: The method described here circumvents this dilemma. Like an optional module, horacoscopically assisted release in prone position (TARP) can be added when it is obvious during posterior surgery that the correction is insufficient.

Results: Between 1996 and 2005, a total of 161 patients (115 male, 46 female) under the age of 30, including 113 cases of idiopathic scoliosis, were released by simultaneous TARP and posterior surgery. Using the two-portal technique, 131 were mobilized from the right and 30 from the left hand side. Average surgical time spanned 69 min, in which on average 3.2 apical segments were addressed. In 3 individuals, an additional retroperitoneoscopic release was used to liberate a rigid lumbar curve. After 10 years, in a prospectively evaluated subgroup of 32 patients with adolescent idiopathic scoliosis, the index curve had maintained a coronal correction of 70 % (immediately post-surgery 75 %), kyphosis was permanently normalized at 30° (Th5-Th12), and indirect rib hump was reduced to 2.2 cm. In 23 out of 32 patients the lumbar curve corrected spontaneously, obviating the need for fusion. In 13 patients, the lower instrumented vertebra lay at Th12 or higher, thus leaving the thoraco-lumbar junction fairly free. Minor complications (Huang 1or 2) occurred in 4 patients; 1 patient with hematothorax required revision. A distance <25 mm from the spine to the chest wall precludes TARP. Other limitations (e.g., pleural adhesions) were not encountered.

Conclusion: Long-term evaluation after 10-18 years shows that an additional thoracoscopically assisted anterior release at the same time as a posterior standard scoliosis procedure is a justified and effective tool, yielding better results and maintaining them.