A thoracolumbar spine orthosis (TLSO) is a back brace that is designed to limit motion in the spine. After a spinal fusion, it takes several months for the bones to knit together and form a solid bone fusion. Having a brace to support the back gives the soft tissues and bones a chance to heal. It also makes you more comfortable during the process.
Orthotists are well acquainted with their craft. They don’t usually need any extra input (unless it’s from the surgeon). However, there is one modification that has been reported to increase the rate of pseudoarthrosis (formation of a false joint at the fusion site). This is the addition of a thigh-extension. The extra piece goes around the thigh and is connected to the bottom of the lumbar jacket. It limits hip motion.
There isn’t any research that has specifically looked at this problem. It could be a coincidence. The number of people in the study was small so it may not be significant. But it does point to the fact that further study is needed to find out what works and what doesn’t (and why).