Boston Brace

The Boston brace is a thoracolumbosacral orthosis, or TLSO — an underarm brace that begins from a pelvic base and encloses the trunk without any neck or chin extension. It was developed in the 1970s and is often built from a prefabricated modular shell that is then customised to the individual, with corrective pads and relief areas added to address a specific curve. Because it sits under the arms and can be worn discreetly beneath clothing, it is far more wearable than the older full-length braces, which is part of why it became so widely adopted.

Like other rigid braces, the Boston brace applies corrective forces to the trunk. Pressure pads push against the prominences of the curve, while relief or expansion areas are left open on the opposite side to give the spine and ribs somewhere to move into. Modern versions, sometimes described as three-dimensional or "3D" Boston braces, are designed to address the rotational and profile components of scoliosis as well as the side-to-side curve. It is typically prescribed for full-time or near full-time wear — commonly in the region of 18 or more hours a day — because, as with rigid bracing generally, results improve with genuine wear time.

The Boston brace is used for growing children and adolescents with idiopathic scoliosis in the moderate range, broadly curves of around 20 to 40 degrees that are progressing or at risk of doing so, with the apex of the curve low enough to be captured by an underarm design. The decision to brace, and the choice of brace, depends on the curve pattern, how much growth remains and the individual young person — which is exactly what a specialist assessment determines.

The Boston brace has one of the longer evidence records of any scoliosis brace. Long-term follow-up studies, some tracking patients more than two decades after treatment, show that most patients treated with the Boston brace do well, with functional outcomes comparable to the general population, and that the brace prevents progression of the curve, rotation and rib prominence rather than permanently straightening the spine. More recent series of the Boston Brace 3D program, assessed against strict Scoliosis Research Society and SOSORT criteria, report that a large majority of single curves and most double curves either improved or stayed stable. The Boston brace also featured in the landmark BrAIST trial, which established that rigid TLSO bracing reduces progression to the surgical threshold and that benefit rises with hours worn. As with bracing in general, no single design has been proven clearly superior, and wear time remains the decisive factor.

A Boston brace is custom-fitted by an orthotist and adjusted over time as the child grows. It is worn under clothing, removed for washing and usually for sport and swimming, and reviewed regularly in clinic alongside periodic X-rays to check the spine is being controlled. It is demanding to wear a rigid jacket through the teenage years, and support from the whole team matters; most young people manage well and continue normal activities. Bracing continues until the spine is skeletally mature, when it is gradually stopped.

• —Danielsson AJ, Nachemson AL. Long-term results after Boston brace treatment in adolescent idiopathic scoliosis. (PMC2743640)
• —Long-term results after Boston brace treatment in late-onset juvenile and adolescent idiopathic scoliosis. (PMC3189160)
• —Short-term outcomes of the Boston Brace 3D program based on SRS and SOSORT criteria. (PMID 35740779 / PMC9221989)
• —Long-term results of Boston brace treatment on vertebral rotation in idiopathic scoliosis. (PMID 8470002)
• —Weinstein SL, et al. Effects of bracing in adolescents with idiopathic scoliosis (BrAIST). N Engl J Med 2013. (PMC3913566)
• —Negrini S, et al. 2016 SOSORT guidelines. (PMID 29435499 / PMC5795289)