'SOSORT consensus paper on brace action: TLSO biomechanics of correction (investigating the rationale for force vector selection)'

A preliminary questionnaire on the topic of 'brace action' relative to the theory of three-dimensional scoliosis correction and brace treatment was developed and circulated to specialists interested in the conservative treatment of adolescent idiopathic scoliosis. A particular case was presented (main thoracic curve with minor lumbar). Several key points emerged and were used to develop a second questionnaire which was discussed and full filed after the SOSORT consensus meeting (Milano, Italy, January 2005).Twenty-one questionnaires were completed. The Chêneau brace was the most frequently recommended. The importance of the three point system mechanism was stressed. Options about proper pad placement on the thoracic convexity were divided 50% for the pad reaching or involving the apical vertebra and 50% for the pad acting caudal to the apical vertebra. There was agreement about the direction of the vector force, 85% selecting a 'dorso lateral to ventro medial' direction but about the shape of the pad to produce such a force. Principles related to three-dimensional correction achieved high consensus (80%–85%), but suggested methods of correction were quite diverse.This study reveals that among participating SOSORT specialists there continues to be a strongly held and conflicting if not a contentious opinion regarding brace design and treatment. If the goal of a 'treatment consensus' is realistic and achievable, significantly more effort will be required to reconcile these differences.Orthotic bracing is the most common non-surgical treatment for Adolescent Idiopathic Scoliosis (AIS), either alone or in combination with exercises. In spite of some negative reports [1-3], brace treatment has been shown to change the natural history of AIS [4] and reduce the incidence of surgery [5-7]. However, the mechanism of action by which braces prevent curve progression, is not well understood.Generally speaking, bracing should unload the growth plates of the apical vertebral bodi