Passive Knee Kinematics Before and After Total Knee Arthroplasty: Are We Correcting Pathologic Motion?

Mihalko, William M.; Ali, Mounawar; Phillips, Matthew J.; Bayers-Thering, Mary; Krackow, Kenneth A.

doi:10.1016/j.arth.2006.12.048

« Previous Next »The Journal of Arthroplasty
Volume 23, Issue 1 , Pages 57-60, January 2008

Passive Knee Kinematics Before and After Total Knee Arthroplasty:

Are We Correcting Pathologic Motion?

William M. Mihalko, MD PhD
- Department of Orthopedic Surgery, University of Virginia, Charlottesville, Virginia
- Reprint requests: William M. Mihalko, MD, PhD, Department of Orthopaedic Surgery, PO Box 800159, Charlottesville, VA 22908-0159.
Mounawar Ali, MD
- Department of Orthopedic Surgery, State University of New York at Buffalo, Kaleida Health, Buffalo, New York
Matthew J. Phillips, MD
- Department of Orthopedic Surgery, State University of New York at Buffalo, Kaleida Health, Buffalo, New York
Mary Bayers-Thering, MS
- Department of Orthopedic Surgery, State University of New York at Buffalo, Kaleida Health, Buffalo, New York
Kenneth A. Krackow, MD
- Department of Orthopedic Surgery, State University of New York at Buffalo, Kaleida Health, Buffalo, New York

Received 16 May 2006; accepted 10 December 2006. published online 09 November 2007.

Abstract

The change in coronal plane deformity throughout a range of flexion before and after total knee arthroplasty (TKA) has not been reported. Unlike most alignment assessments traditionally reporting coronal plane alignment in a standing position under static conditions, this study reports deformity throughout the flexion arc before and after deformity correction. One hundred fifty-two TKA patients using the anteroposterior axis for femoral component rotation and computer navigation techniques were included in the study. Deformity before TKA ranged from 17.5° varus (deformity apex away from the midline) to 20.5° valgus (deformity apex toward the midline) in full extension. Before TKA, deformity was not constant through an arc of motion and significantly decreased with flexion of 60° and more (P < .01). The deformity after performing a TKA was not different (P = .478) throughout the flexion arc. The data determined that deformity is not constant throughout flexion in osteoarthritic knees preoperatively and that deformity throughout flexion can be corrected with the use of conventional alignment techniques during TKA.

Key words: knee, arthroplasty, kinematics, alignment, computer navigation