Minireviews
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Sep 18, 2015; 6(8): 614-622
Published online Sep 18, 2015. doi: 10.5312/wjo.v6.i8.614
Physical activity after total knee arthroplasty: A critical review
Roger J Paxton, Edward L Melanson, Jennifer E Stevens-Lapsley, Cory L Christiansen
Roger J Paxton, Jennifer E Stevens-Lapsley, Cory L Christiansen, Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado, Denver, Aurora, CO 80045, United States
Edward L Melanson, Division of Endocrinology, Metabolism, and Diabetes, University of Colorado, Denver, Aurora, CO 80045, United States
Edward L Melanson, Division of Geriatric Medicine, University of Colorado, Denver, Aurora, CO 80045, United States
Author contributions: All authors contributed to this manuscript.
Supported by Grants from the National Institutes of Health, Nos. NIH K23-AG029978 and NIH T32-000279.
Conflict-of-interest statement: None.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Roger J Paxton, PhD, Postdoctoral Fellow, Physical Therapy Program, Department of Physical Medicine and Rehabilitation, University of Colorado, Denver, Anschutz Medical Campus, Mail Stop C244, 13121 East 17th Avenue, Aurora, CO 80045, United States. roger.paxton@ucdenver.edu
Telephone: +1-303-7249590 Fax: +1-303-7242444
Received: March 17, 2015
Peer-review started: March 23, 2015
First decision: April 27, 2015
Revised: June 17, 2015
Accepted: June 30, 2015
Article in press: July 2, 2015
Published online: September 18, 2015
Abstract

Total knee arthroplasty (TKA) is the most commonly performed elective surgery in the United States. TKA typically improves functional performance and reduces pain associated with knee osteoarthritis. Little is known about the influence of TKA on overall physical activity levels. Physical activity, defined as “any bodily movement produced by skeletal muscles that results in energy expenditure”, confers many health benefits but typically decreases with endstage osteoarthritis. The purpose of this review is to describe the potential benefits (metabolic, functional, and orthopedic) of physical activity to patients undergoing TKA, present results from recent studies aimed to determine the effect of TKA on physical activity, and discuss potential sources of variability and conflicting results for physical activity outcomes. Several studies utilizing self-reported outcomes indicate that patients perceive themselves to be more physically active after TKA than they were before surgery. Accelerometry-based outcomes indicate that physical activity for patients after TKA remains at or below pre-surgical levels. Several different factors likely contributed to these variable results, including the use of different instruments, duration of follow-up, and characteristics of the subjects studied. Comparison to norms, however, suggests that daily physical activity for patients following TKA may fall short of healthy age-matched controls. We propose that further study of the relationship between TKA and physical activity needs to be performed using accelerometry-based outcome measures at multiple post-surgical time points.

Keywords: Physical activity, Knee osteoarthritis, Self-report, Total knee arthroplasty, Accelerometer

Core tip: Little is known about the influence of total knee arthroplasty (TKA) on physical activity levels. This review describes the potential benefits of physical activity to patients undergoing TKA, presents results from recent studies aimed to determine the effect of TKA on physical activity, and discusses potential sources of variability and conflicting results for physical activity outcomes. Several studies indicate that patients describe themselves to be more physically active after TKA than before surgery. Accelerometry-based outcomes indicate that physical activity for patients after TKA may remain at or below pre-surgical levels. Daily physical activity for patients following TKA may fall short of healthy age-matched controls.