One large issue in bracing for scoliosis is patient compliance, as mentioned above. Compliance is often impacted by the other above-mentioned factors (psycho-social comfort, exercise), but there are others also, including ability to eat and move, pain, and physical deformation.
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Back braces, especially the Boston brace, puts a great deal of pressure on the abdomen and can make digestion uncomfortable. Scoliosis braces, like those used for correcting post-operatively and for fractures, inhibit motion to a large extent, though percentages are difficult to find.
Patients frequently complain about the inability to tie their own shoes, sit on the floor, etc. Bracing is also painful, though the body can adapt to tolerate the pain. Braces can also deform the patient’s existing bone structures, most notably the hips, though there have been complaints about rib cage deformities as well