There are plenty of simulations for spinal fusion procedures available online, as well as real surgical videos that demonstrate what occurs during spinal fusion operations. Although it can be difficult to see what occurs in real surgical videos, surgical simulations with 3D spinal fusion will quickly show significant aspects of the procedure without explaining what is happening.
One region usually skipped over is surgical soft tissue release. This surgical release eliminates stretched ligaments and other soft tissue which lowers the amount of straightening of the spine.
In addition to soft tissue, bone is often often removed during this process, so that the spine can be better aligned with the metal rods that are implanted surgically.
This operation is part of the overall spinal fusion surgery and can differ in depth depending on how "stiff" the spine is. The stiffer the spine, the easier it is to straighten out and hence the more "release" is required during surgery. The article will cover in detail what is done during surgical release when scoliosis is performed on the spinal fusion procedure.
infographic by: scoliosiscarecenters.com