[1] Mayo Clin, Dept Phys Med & Rehabil, Rochester, MN 55905 USA
[2] Mayo Clin, Dept Anesthesiol, Pain Div, Rochester, MN 55905 USA
[3] Mayo Clin, Dept Radiol, Rochester, MN 55905 USA
[4] Mayo Clin, Dept Phys Med & Rehabil, Jacksonville, FL 32224 USA
[5] Mayo Clin, Dept Anesthesiol, Jacksonville, FL 32224 USA