[1] UNIV PENN,PRESBYTERIAN MED CTR,PHILADELPHIA,PA 19104
[2] TUFTS UNIV,SCH MED,BOSTON,MA 02111
[3] UNIV TORONTO,DEPT SURG,TORONTO M5S 1A1,ONTARIO,CANADA
[4] UNIV CALIF DAVIS,SACRAMENTO MED CTR,SCH MED,DEPT ORTHOPAED,SACRAMENTO,CA 95817
[5] CLEVELAND CLIN EDUC FDN,JOINT REPLACEMENT & ARTHRITIS SURG SECT,CLEVELAND,OH 44106
[6] INDIANA UNIV,SCH MED,DEPT ORTHOPAED SURG,INDIANAPOLIS,IN 46202
[7] OREGON HLTH SCI UNIV,SCH MED,DIV ORTHOPAED,EUGENE,OR
[8] HOSP SICK CHILDREN,DIV ORTHOPAED SURG,TORONTO M5G 1X8,ONTARIO,CANADA
[9] HOSP UNIV PENN,DEPT ORTHOPAED SURG,PHILADELPHIA,PA 19104