Abstract
Introduction
To evaluate in a retrospective study the capability of Shilla technique in preventing the crankshaft phenomenon in the treatment of the severe scoliosis in young children.
Methods
11 scoliotic children (3M, 8F), Tanner 0, aged from 4 years 6 months to 11 years 6 months were operated by Shilla procedure and were reviewed with a followup from 3 years to 6 years 4 months.7 patients had their final fusion. The number of procedure, except for final arthrodesis was one in 5 patients and two in 6 patients.
Results
The mean preoperative Cobb angle was 57° (thoracic curve 67°, lumbar curve 55°). The growth continued in all children from 67 cm of the sitting height on initial examination to 72.5 cm at final follow-up. For the coronal angle, it was corrected form 57° to 34° at immediate post-op than an increase to 50° at final follow-up. In 7 children, the initial post-op correction was not maintained due to the crankshaft phenomenon observed in both fused instrumented apex curves (67° → 35° (immediate post op) → 51° on final follow-up) as well as in the non-fused non instrumented apex curves (54° → 40° (immediate post op) → 55° on final follow-up).
Discussion and Conclusion: If the crankshaft was expected in bridged curves it also occurred in the apex fused-instrumented curves. Age of the children of 10 years 9 months, right in the growth spur appears to be its main cause. The children with controlled curves had a mean age of 7 years 8 months. In conclusion, the Shilla technique, even in apex fused instrumented curves was not able to control the crankshaft phenomenon during growth spurt. This should be taken in consideration for the timing of the final fusion.