1. Department of Anesthesiology, University of Texas Health Science Center, San Antonio, Texas
2. School of Medicine, University of Texas Health Science Center, San Antonio, Texas
3. Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center, San Antonio, Texas
4. Department of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, Utah
5. Department of Anesthesiology and Perioperative Medicine, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania
6. Department of Sports Medicine, Southwest Sport and Spine Center, Fort Worth, Texas
7. Department of Anesthesiology, Sigma Pain Clinic, San Antonio, Texas, USA