Catherine A. Holt received the B.Eng. degree in mechanical engineering from University College Cardiff, U.K., in 1988 and the Ph.D. degree from the University of Wales, Cardiff, U.K., in 1993. She received a P.G.Dip. in clinical gait analysis from the University of Strathclyde in 1998. She is currently a Lecturer in biomechanics and materials at the Cardiff School of Engineering, Cardiff University. She was previously employed as a Senior Research Associate and as the Manager of the motion-analysis laboratory in the Medical Engineering Research Group, Cardiff University. Her research interests include three-dimensional (3-D) motion analysis and biomechanical modeling of human joints; the characterization of joint function using kinematic and kinetic indicators; osteoarthritic (OA) and total knee-replacement function; and spinal instrumentation and its effectiveness in terms of successful fusion techniques.