An Instructional Course Lecture, The American Academy of Orthopaedic Surgeons.*Printed with permission of The American Academy of Orthopaedic Surgeons. This article will appear in Instructional Course Lectures, Volume 46, The American Academy of Orthopaedic Surgeons. Rosemont, Illinois, March 1997.**No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. No funds were received in support of this study.***Cincinnati Sportsmedicine and Orthopaedic Center, Deaconess Hospital, 311 Straight Street. Cincinnati. Ohio 45219.****Department of Orthopedic Surgery, Sports Medicine Section, Rush Medical College, Rush-Presbyterian-St. Luke's Medical Center, 1725 West Harrison Street, Suite 1063, Chicago, Illinois 60612.*****MedSport, Department of Surgery, University of Michigan, P.O. Box 363, Ann Arbor Michigan 48106-0363.