[1] MIT, Inst Med Engn & Sci, Cambridge, MA 01239 USA
[2] Harvard MIT Program Hlth Sci & Technol, Cambridge, MA 02139 USA
[3] Harvard Univ, John A Paulson Sch Engn & Appl Sci, Cambridge, MA 01238 USA
[4] Harvard Univ, Wyss Inst Biol Inspired Engn, Cambridge, MA 02138 USA
[5] Beth Israel Deaconess Med Ctr, Dept Orthopaed Surg, Boston, MA 02215 USA
[6] MIT, Dept Mech Engn, Cambridge, MA 02139 USA
[7] McGill Univ, Dept Mech Engn, Montreal, PQ H3A 0C3, Canada