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The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation
Published on: July 22, 2019
Lower impulsive loadings following intensive weight loss after bariatric surgery in level and stair walking: a
Timo Bragge1, Tarja Lyytinen2, Marko Hakkarainen1
1Department of Applied Physics, University of Eastern Finland, Finland.
Background:
There are currently very few of studies which have evaluated the role of bariatric surgery in joint loadings and changes in gait. We wanted to examine how impulsive loading would change level and stair walking in severely or morbidly obese subjects after they had undergone bariatric surgery and weight loss.
Methods:
Thirteen female and three male adults aged between 30 and 63 years, cleared for Roux-en-Y gastric bypass, were recruited into this study. All subjects were severely or morbidly obese i.e., body mass index was >35 kg/m(2). The measurement methods consisted of triaxial skin mounted accelerometers and ground reaction force (GRF); conducted at two different predetermined gait speeds.
Results:
The average weight loss was 27.4 (SD8.7) kg after 8.8 (SD3.9) months of follow-up period. Most of the absolute GRF parameters decreased in proportion to weight loss. However, medio-lateral GRF parameters decreased more than expected. The general trend in the knee accelerations demonstrated lower impulsive loadings in both axial and horizontal directions after weight loss. We did not observe any significant changes in stair walking.
Conclusions:
Weight loss after bariatric surgery not only induces a simple mass-related adaptation in gait but also achieves mechanical plasticity in gait strategy.

