Anterior thoracoscopic spine release in deformity surgery: a meta-analysis and review

Abstract

Videoassisted thoracoscopic surgery (VATS) allows the surgeon to perform an anterior thoracoscopic spine release for spinal deformities. It is an alternative to open thoracotomy. Several years after its introduction the present author gives an update on the indications, surgical techniques, results, and complications of this new technology. A metaanalysis of previously published papers is organized in tables in an attempt to answer all the questions and controversies that this technique has aroused. A series of ten selected articles were available for review, comprising a total of 151 procedures. No study had any long-term follow-up. Most series were pediatric and involved a variety of etiologies (mostly neuromuscular, adolescent idiopathic scoliosis, and Scheuermann's kyphosis). The surgical technique was for most authors a convex side approach in the lateral decubitus through four or more ports in the anterior or midaxillary line. Single lung ventilation was used in most cases. Posterior surgery was carried out the same day in most cases. The total number of discs excised varied between 4 and 7, but the quality of disc excision was rarely reported. Most authors carried out a spine fusion at the time of the disc release. The total VATS procedure lasted between 2 h 30 min and 4 h, depending on the series and the surgeon's previous experience. In most series curves were in the range of 55°-80°, with an average of 65°. The percentage of Cobb angle correction was 55%-63% after VATS and posterior spine fusion. For kyphotic deformities only one series had significant numbers to allow conclusions to be drawn. The mean preoperative Cobb angle was 78°and postoperatively the kyphosis was corrected to 44°. Length of hospital stay was quite similar in most series and was around 9 days. The cost of the VATS procedure was studied in one series and was found to be 28% more expensive than thoracotomy. The total complications reported were 18%; most were pulmonary complications with prolonged ventilatory support in patients with neuromuscular pathologies. The VATS procedure has been used with success in most series for pediatric curves (average Cobb angle of 65°or kyphosis of 75°). No report of the surgical outcome (balance, rate of fusion, rib hump correction, cosmetic correction, pain, and patient satisfaction) was available for any series. Further prospective study including these parameters will be required to determine the real benefit of such procedures to the patient, bearing in mind that the correction of spinal deformities is the result of the surgeon's experience, skill, and the available technology. Key words Vincent ArletAnterior thoracoscopic spine release in deformity surgery: a meta-analysis and review Received: 3 September 1999 Accepted: 6 September 1999 No support from any source was received for he completion of this study.

Is anterior release effective to increase flexibility in idiopathic thoracic scoliosis? Assessment by traction films

“…With the advent of thoracoscopic techniques for spinal surgery, numerous studies have been published concerning anterior release in AIS [1,2,[11][12][13][18][19][20][21][22][23][24][25][26]. Excision of the intervertebral discs prior to posterior instrumentation is believed to impart additional flexibility and it has been presumed that disc excision improves the correction rate [12,19,20].…”

“…The optimal indication for an anterior release in AIS remains unclear: it has been recommended for curves greater than 60° [20], 70° [24], curves greater than 100° [4] and curves greater than 40°i n fulcrum bending [6]. In a meta-analysis it has been shown that in most series using thoracoscopic anterior release, the Cobb angle averaged 65° [2] and even patients with a scoliosis of 42°have been anteriorly released [1]: we are convinced that the additional morbidity by the anterior release is not justified in such cases. Recent paper showed that there is no need for an anterior release even for curves in the 70°-90°range [3] and that in curves up to 100°a single posterior approach with pedicle screw constructs leads to the same coronal correction rate [14].…”

“…With the advent of thoracoscopic procedures, the anterior release has become increasingly popular even in adolescent idiopathic scoliosis (AIS) [1,2,5,[11][12][13][18][19][20][21][22][23][24][25]. The aim of the disc excision is to increase spinal flexibility and to improve subsequent deformity correction by posterior instrumentation.…”

Posterior fusion only for thoracic adolescent idiopathic scoliosis of more than 80°: pedicle screws versus hybrid instrumentation

“…Kim et al [25] recently reported that an open anterior approach may have a deleterious effect on pulmonary function for as long as 5 years postoperatively, after surgical treatment of adolescent idiopathic scoliosis. Video-assisted thoracoscopy (VAT), used for the anterior release, followed by posterior instrumentation for scoliosis treatment [2,29,36,37] can minimize, but not eliminate, the negative effect on pulmonary function, as reported by Newton et al [36].…”

Comment regarding “Is anterior release effective to increase flexibility in idiopathic thoracic scoliosis? Assessment by traction films” (A. Hempfing et al.)

“…Recent papers on the need of anterior release in curves between 70°and 100°have shown that the anterior release was unnecessary with the modern segmental instrumentation [3][4][5]. In 2000, we published a meta-analysis of anterior release done with thoracoscopic instrumentation and to our surprise the average Cobb angle of the curves being released was only 65°with a maximum of 80° [6]. Today these thoracoscopic releases are being performed at many centers despite the strong evidence shown as in this paper, that it is unnecessary and of little benefit.…”