PT's what's your take on this?

Wisdom seeker, I think that the problem is more likely in the area of L4-5 than S2. The muscles that make up the erector spini include a group called the multifidi. These are small muscles that help to stabilize the spine and rotate it. They are short in their length spanning only a vertebrae or two. They are easily injured and painful. There is also the possibility that you have injured a facet joint. These are the joints that are located at the rear of the vertebrae. They are responsible for guiding the movements of the vertebrae. They have a capsule surrounding them and have a nerve supply. If injured they will cause significant pain, loss of mobility, and sensory problems.