Randomized Clinical Trial
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Dec 6, 2021; 9(34): 10604-10615
Published online Dec 6, 2021. doi: 10.12998/wjcc.v9.i34.10604
Effects of lower body positive pressure treadmill on functional improvement in knee osteoarthritis: A randomized clinical trial study
Hong-Xin Chen, Yao-Xuan Zhan, Hai-Ning Ou, Yao-Yao You, Wan-Ying Li, Shan-Shan Jiang, Mei-Feng Zheng, Lin-Zi Zhang, Ke Chen, Qiu-Xia Chen
Hong-Xin Chen, Yao-Yao You, Wan-Ying Li, Mei-Feng Zheng, Department of Rehabilitation Medicine, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou 510700, Guangdong Province, China
Yao-Xuan Zhan, Qiu-Xia Chen, Department of General Medicine, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou 510700, Guangdong Province, China
Hai-Ning Ou, Guangzhou Key Laboratory of Enhanced Recovery After Abdominal Surgery, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou 510700, Guangdong Province, China
Shan-Shan Jiang, Department of Rehabilitation Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu Province, China
Lin-Zi Zhang, Department of Rehabilitation Medicine, Guangdong Pharmaceutical University, Guangzhou 510006, Guangdong Province, China
Ke Chen, Department of Osteology, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou 510700, Guangdong Province, China
Author contributions: Chen HX and Zhang YX contributed equally as co-first authors; Chen K and Chen QX contributed equally as co-correspondence authors; Chen QX, Chen K, Chen HX and Zhan YX were responsible for the study conception and design, data analysis and interpretation, and manuscript drafting; Ou HN, You YY, Li WY, Jiang SS, Zheng MF and Zhang LZ were responsible for the data collection and data analysis; all authors reviewed and approved the final version to be published.
Institutional review board statement: This study was approved by the Medical Ethics Association of the Fifth Affiliated Hospital of Guangzhou Medical University (No. KY01-2018-10-18).
Clinical trial registration statement: This study was registered at the China Clinical Trial Registration Centre (No. ChiCTR1800017677).
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The author reports no conflicts of interest in this work.
Data sharing statement: The data used to support the findings of this study are available from the corresponding author upon request.
CONSORT 2010 statement: The manuscript was checked according to the CONSORT 2010.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Qiu-Xia Chen, MD, Associate Chief Physician, Department of General Medicine, The Fifth Affiliated Hospital of Guangzhou Medical University, No. 621 Gangwan Road, Huangpu District, Guangzhou 510700, Guangdong Province, China. zhh-yy@163.com
Received: March 21, 2021
Peer-review started: March 21, 2021
First decision: April 29, 2021
Revised: August 20, 2021
Accepted: September 16, 2021
Article in press: September 16, 2021
Published online: December 6, 2021

Knee joint pain and stiffness are the two main symptoms of knee osteoarthritis (OA) and thus restrict a patient’s activities, such as walking and walking up and downstairs. The lower body positive pressure (LBPP) treadmill as one of the emerging body weight support system devices brings new hope for exercise-related rehabilitation for knee OA patients.


To investigate the biomechanical effects and the subjective clinical assessment of LBPP treadmill walking exercise when compared with conventional therapy in mild to moderate knee OA patients.


Eighteen patients with mild-to-moderate knee OA were recruited in this randomized controlled trial (RCT) study. The eligible knee OA patients were randomly assigned to two groups: LBPP and control groups. The patients in the LBPP group performed an LBPP walking training program for 30 min/session per day, 6 d per week for 2 wk whereas the patients in the control group performed walking on the ground for the same amount. All patients underwent clinical assessments and three-dimensional gait analysis at pre- and 2-wk post-treatment.


The Western Ontario and McMaster Universities Arthritis Index and visual analog scale scores in both the LBPP group and control group were found to decrease significantly at the post-treatment point than the pre-treatment point (LBPP: 70.25 ± 13.93 vs 40.50 ± 11.86; 3.88 ± 0.99 vs 1.63 ± 0.52; control: 69.20 ± 8.88 vs 48.10 ± 8.67; 3.80 ± 0.79 vs 2.60 ± 0.70, P < 0.001). Moreover, compared with the control group, the LBPP group showed more improvements in walking speed (P = 0.007), stride length (P = 0.037), and knee range of motion (P = 0.048) during walking, which represented more improvement in walking ability.


The results of our RCT study showed that the LBPP group has a greater effect on improving gait parameters than the conventional group, although there was no significant advantage in clinical assessment. This finding indicates that LBPP treadmill walking training might be an effective approach for alleviating pain symptoms and improving lower extremity locomotion in mild to moderate knee OA patients.

Keywords: Lower body positive pressure, Three-dimensional gait analysis, Walking training, Rehabilitation, Knee osteoarthritis

Core Tip: To our best knowledge, this is the first randomized controlled trial focusing on lower body positive pressure (LBPP) training in knee osteoarthritis rehabilitation. Both subjective clinical assessment and objective biomechanical assessments were used in this study. The LBPP group showed more improvements in pain relief and gait improvement than the conventional group. LBPP treadmill exercise training could be considered an effective approach for patients with knee osteoarthritis.