RESUMO
BACKGROUND: Numerous techniques for determining the flexibility of the scoliotic cure have been invented. Our contribution includes combining traction and translation forces; we introduced a new radiographic technique that can be claimed to be capable of a far more precise prediction of the scoliotic curve flexibility. METHODS: In this study, we compared the flexibility rate obtained on standard fulcrum bending radiographs with modified ones in 50 consecutive patients with adolescent idiopathic scoliosis (78 curves) who had referred to our clinics from September 2009 to July 2012. In this new technique, we added traction force to the upside extremities. Then, flexibility rate of the two methods was compared statistically. RESULTS: The study included 50 cases (43 female and 7 male) aged 10-17 (14.5 ± 2.1 years) comprising 78 scoliotic curves. Curves magnitude varied from 25° to 135° (61.4° ± 21.3°). The mean flexibility rate with standard fulcrum bending radiograph was 38.8% ± 20%. This index increased to 58.3% ± 22.2% (which is statistically significant, p < 0.0005) as a result of implementing the modified fulcrum bending method. Excluding the proximal thoracic curves due to the limited number of the cases, the difference between flexibility rate with this new technique in main thoracic and thoracolumbar/lumbar curves is not statistically significant (p > 0.05). CONCLUSIONS: The modified fulcrum bending method we introduced has some inevitable disadvantages; however, in the era of modern and vigorous segmental spinal instrumentation, with combining traction and translation forces in their best biomechanical state, it can demonstrate the scoliotic curve flexibility much more efficiently.