Here is an amazing video by an artist who recovered from debilitating chronic pain from a car accident. She still has pain every day, but has learned to control it by graded exposure to handstands.
Part of recovering from chronic pain is graded exposure to different levels of movements and activities that eventually reduce the threat your central nervous system perceives. Reducing threat increases pain threshold and improves function.
It's really inspiring to see how others continue to improve their quality of life and manage their pain states.