The concept of bracing a scoliotic curve to correct and prevent progression of the deformity has been known since Antiquity and is now a common and accepted method of treatment. Although braces are currently the most common form of nonoperative treatment prescribed to manage adolescent idiopathic scoliosis (AIS), the value of bracing remains controversial and subject to debate.
As is the case for many orthopaedic treatments that are considered by clinicians as a gold standard, the scientific proof of the efficacy of bracing in AIS has yet to be clearly demonstrated. The value of bracing is supported by numerous level IV and some level III studies, but still awaits level I evidence. The strongest evidence comes from the study by Nachemson et al, the only prospective and controlled but non-randomised level II study available. It is seconded by the level III meta-analysis of Rowe et al. Both studies strongly support the efficacy of bracing in AIS. The Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) is the only level I multi-centre randomised and controlled trial currently underway. It may provide more solid evidence over the next decade, but it is unfortunately handicapped by very low recruitment numbers that will inevitably lead to questions about its validity and its application to the general population of subjects with AIS.
Several innovative types of braces have been designed by clinicians to reduce or control the progression of scoliosis. Among these, the Boston brace system slowly replaced the Milwaukee brace as the most popular brace design in North America in the 1980s, while a decade later, night-time bracing (Charleston or Providence Braces) was suggested as a valid alternative.
The conventional brace design procedure is empirical and most frequently employs a cast model of the patient’s trunk as a guide to design the brace. The cast is then modified by an orthotist using location of 2D pressure points determined on 2D radiographs, despite the wide recognition that the scoliotic deformity is three dimensional. Because of this limitation, computer-assisted brace design using 3D reconstructed models of scoliosis is being investigated as a more valid alternative. Non-rigid designs, such as the SpineCor brace, have been introduced as a possible alternative to standard bracing, but remain to be clearly validated.
Current recommendations for bracing in AIS thus remain empirical. Bracing is suggested for AIS curves between 20 and 45 degrees of Cobb angle in immature (Risser 0 to III) subjects, and, more specifically, in patients with a clearly demonstrated progressive curve.
The efficacy of bracing in infantile and juvenile idiopathic scoliosis, as well as in neuromuscular or congenital scoliosis, remains to be determined.
References
- Nachemson A.L. et al, J Bone Joint Surgery Am.77(6): 815-822, 1995.
- Rowe D.E. et al, J Bone Joint Surg Am. 79:664-674, 1997.
- Labelle H. et al, Spine, 32(8):835–843, 2007
- Coillard C. et al, J Pediatr Orthop. 27(4):375-9, 2007.
Reprinted with permission from the Summer 2009 issue of COA Bulletin