Back braces have a place in treatment of acute pain episodes and the rehab for post-surgical patients. The lumbar brace works by creating increased pressure in the abdominal cavity which shares the weight bearing load of the spine. This in turn reduces the lumbar lordosis.
The problem with longer term use of the lumbar brace is weakening of the anterior abdominal muscles. Instead of the patient pulling these muscles “in” to use the anterior abdominal wall as a brace, the patient will tend to push this abdominal wall “out” against the brace. This is an energy saving maneuver but against the normal pattern of standing and weakens these muscles.
Nonetheless, these braces are very helpful for certain problems. One of my Physician’s Assistants just yesterday developed pain from an annular tear and the only way he could stand is with a lumbar brace. He estimated that the brace reduced his standing pain by at least 50%.