SpineCor vs. natural history - explanation of the results obtained using a simple biomechanical model

In the recent peer reviewed literature the SpineCor is described as an effective method of treatment for patients with scoliosis. However until recently no prospective controlled end-result study is presented comparing the results obtained with this soft brace to natural history. The objective was to determine whether the results obtained by the use of the SpineCor are better than natural history during pubertal growth spurt. The method employed prospective comparison of the survival rates of SpineCor treatment vs. natural history with respect to curve progression during pubertal growth spurt. 12 Patients with Cobb angles between 16 and 32 degrees (at average 21 degrees) during pubertal growth spurt are presented as a case series treated with the SpineCor. Survival rate of this sample is described and compared to natural history (SRS brace study 1995). All girls treated in both studies were at risk for being progressive with the first clinical signs of maturation (Tanner 2-3). During the pubertal growth spurt most of the patients (11/12) with SpineCor progressed clinically and radiologically as well (at least 5 degrees). Progression could be stopped changing SpineCor to the Chêneau brace in most of the sample described (7/10). The avarage Cobb angle at the start of treatment with the SpineCor was 21.3 degrees, after an average observation time of 21.5 months 31 degrees. At 24 months of treatment time 33% of the patients with the SpineCor where still under treatment with their original bracing concept, at 72 months follow-up time 8 % of the patients with the SpineCor survived with respect to curvature progression. Survival proportion in the SpineCor sample, though was 0.08, while in the natural history cohort it was 0.34. The SpineCor treatment during pubertal growth spurt seems to lead to a worse outcome than observation only. The use of a simple biomechanical model explains that in the brace the compression forces exceed the lateral forces used for the corrective movement. Therefore SpineCor does not seem to be indicated as a treatment during pubertal growth spurt.