Idiopathic scoliosis, a sideways curve of the spine of unknown cause in adolescence, is now believed to require active treatment in only about 10 percent of cases. When treatment is called for, a cast or a device called a Milwaukee brace is widely used.
At least 60 percent to perhaps 80 percent of the cases are in girls, and girls tend to have worse curves and greater progression.
A review of studies on scoliosis and its treatment found that the Milwaukee brace, which has been in wide use since the late 1940s, has been the subject of few long-term studies to evaluate its results.
Of the studies, most did not keep track of the progression of the curvature, making it uncertain whether patients with braces would have gotten worse without it. Bracing tends to stop the curve’s progression in 85 to 90 percent of patients, but there is wide variation in response.
Most common is a moderate correction while the brace is worn with slow, steady progression back to the original curve after its use is tapered off.