Prospective study and new concepts based on scoliosis detorsion of the first 225 early in-brace radiological results with the new Lyon brace: ARTbrace

BACKGROUND The symmetrical Lyon brace is a brace, usually used to maintain correction after a plaster cast reduction in the Cotrel's EDF (Elongation-Derotation-Flexion) frame. The new Lyon brace or ARTbrace is an immediate corrective brace based on some of the principles of the plaster cast which are improved due to advances in CAD/CAM technology. The aim of this paper is to describe concepts of this new brace to be not only a replacement of the plaster cast, but also a definitive brace. METHODS Instead of a plaster cast, three segmental CAD/CAM moulds are made with the instantaneous full 3D raster stereography digitizer (Orten):In self axial elongationIn shift and lumbar lordosisIn shift and thoracic kyphosis A specific software (OrtenShape) makes up the overlay of the three moulds. Mould 1 is used for the pelvis and the shoulders mould 2 for the lumbar segment and mould 3 for the thoracic segment. The mathematical basis of the ARTbrace is the torso column which is a circled helicoid with horizontal circle generator. A torso column is reproduced in the opposite direction of the scoliosis. Like the plaster cast, the ARTbrace is worn for a "total time" of 24 hours 7 days a week without modifying the standard protocol of the Lyon brace reduction. The prospective controlled cohort observational study of the 225 first patients treated since May 2013 is reported below. RESULTS The in-brace immediate reduction is: 0.7, i.e. 40% better with the ARTbrace than with a plaster cast. The correction of flat back is 9° (from 18°.4 to 28°.5 kyphosis Cobb angle). The improved aesthetic appearance is equal for rib hump and ATR. CONCLUSION This first paper is an introduction with very short results and does not prejudge the final outcome. The ARTbrace can be used not only to replace the plaster cast, but also as a definitive brace. The new segmental moulding with final detorsion is even more efficient and to this day the ARTbrace is the most effective to reduce the Cobb angle of scoliosis.