1. Department of Anesthesiology and Pain Medicine The University of Kansas Medical Center Kansas City Kansas USA
2. Department of Physical Medicine and Rehabilitation The University of Kansas Medical Center Kansas City Kansas USA
3. Department of Physical Medicine and Rehabilitation University of Pittsburgh Medical Center Pittsburgh Pennsylvania USA
4. Department of Anesthesiology University of Utah Salt Lake City Utah USA
5. Department of Physical Medicine and Rehabilitation Detroit Medical Center Detroit Michigan USA
6. Cantor Spine Center at the Paley Orthopedic & Spine Institute West Palm Beach Florida USA
7. Department of Anesthesiology and Perioperative Medicine Mayo Clinic Rochester Minnesota USA