1. Center for Spine Health, Cleveland Clinic Foundation, USA
2. School of Medicine, Case Western Reserve University, USA
3. Department of Neurosurgery, University Hospitals Cleveland Medical Center, USA
4. College of Medicine, Central Michigan University, USA
5. Department of Neurosurgery, University of Cincinnati, USA
6. Department of Neurosurgery, Ascension Seton Brain and Spine Institute, USA
7. Department of Neurosurgery, University of Minnesota, USA