1. Department of Physical Medicine and Rehabilitation, Case Western Reserve University, Cleveland, Ohio, USA
2. MetroHealth Research Institute, Case Western Reserve University, MetroHealth Medical Center, Cleveland, Ohio, USA
3. Department of Neurosurgery, Case Western Reserve University, Cleveland, Ohio, USA
4. Department of Anesthesiology, Case Western Reserve University, Cleveland, Ohio, USA
5. Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
6. Research Service, Louis Stokes Cleveland VA Medical Center, East Boulevard, Cleveland, Ohio, USA