The Effect of Pilates on Knee Joint Deformities
Sam’s world view
Each month we hear from Sam Wood - she summarises the most recent articles published in the Pilates industry.
In 2021, researchers in Korea conducted a study on the biomechanical effects of Pilates on genu varum, also known as bowlegged alignment (the legs curve outward at the knees while the feet and ankles touch). Genu varum contributes to abnormal gait, and gait deviations can lead to lower limb dysfunction and, ultimately, joint pathologies such as early onset osteoarthritis (OA) . The authors hypothesized that improving trunk posture and stability via Pilates exercises would help correct the genu varum seen in their young subjects. Although there have been many studies on gait and varus alignment, these have mostly focused on older patients who had already developed early onset arthritis or on surgical treatment results. The aim of this study was to evaluate the effectiveness of Pilates exercise on gait and leg misalignment in young subjects. If knee varus and gait abnormalities can be managed via exercises, the probability of young people with these issues developing early onset arthritis can be decreased.
In the study, 23 female college students (aged 20-24) with X-ray verified genu varum were randomly assigned to a Pilates exercise-training group or a control group. X-rays and a gait analysis were done on all participants at the beginning of the study. The Pilates group did a generic mat Pilates routine for 60 minutes per session, three days per week, for 10 weeks. After 10 weeks, the gait analysis and X-rays were repeated. In the Pilates group, X-rays verified improvement in knee alignment, though mostly in the nondominant leg. The authors feel that perhaps the program needed to be longer than 10 weeks to have the substantial gains in strength needed to create a structural change on the dominant leg. Postintervention gait analysis showed some important changes as well. The maximum extension moment of the knee joint in the end support phase was significantly increased, whereas the maximum flexion moment in the middle of the stance phase was significantly decreased. A moment is a biomechanical measurement of how much rotational force muscles and other structures need to control movement, so this indicates the ability to stabilize with the extensor muscles during walking and more efficient shock absorption. Additionally, maximal internal rotation and adductor moments of the hip joint were significantly increased in the Pilates group during the end stage of the stance phase of gait, which indicates more hip joint muscle control (Moisio et al. 2003). In the control group, X-rays did not show any significant changes in alignment, and gait analysis showed no positive gait pattern changes.
The results of this study suggest that Pilates exercises may be beneficial for females with genu varum by helping to improve both their static alignment and giving them a more balanced gait. Since knee joint deformities and abnormal gait patterns often lead to dysfunction and an early onset of arthritis, one can argue that consistent Pilates could be preventative for such pathologies. The authors point out that if the Pilates exercise program in the study had lasted more than 10 weeks and had focused more on the lower body including more weight-bearing exercises (rather than the generic mat routine), it could have been even more effective.
References
Song, O., K. Seo, D.M. O’ Sullivan, and J. Park. 2021. “A Biomechanical Analysis of the Effect of Pilates Exercise on Female College Students with Knee Joint Deformity.” The Asian Journal of Kinesiology 23 (3): 20-28.
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