Individual analysis of dynamic stability for twenty-four Tai Chi forms among persons with knee osteoarthritis: A pilot study

Background:
Tai Chi (TC) training has been increasingly used to prevent falls. However, the underlying biomechanical mechanisms of TC training which influence fall risk remain unknown. As a result, the selection of TC forms differs among studies, leading to inconsistent results.

Research question:
Is dynamic stability different between the simplified 24 Yang-style TC forms among adults with knee osteoarthritis?

Methods:
Ten participants with mild to moderate knee osteoarthritis were recruited. Under one-on-one instruction by an experienced TC master, each participant learned how to correctly perform the 24-form TC movements. Participants' full-body kinematic and kinetic data was collected during walking trials and performance of the respective TC forms. Their dynamic stability was calculated in both sagittal and frontal planes and compared between each TC form and regular walking.

Results:
The results indicate that dynamic stability in both planes significantly varies among forms. Moreover, some forms pose a greater challenge to dynamic stability in comparison to others. The most challenging TC forms are Form 8 for stability in the sagittal plane and Form 10 in the frontal plane. Among all forms, Form 1 appears to be the least challenging.

Significance:
Our findings could provide foundational information to identify the best TC forms for optimizing the effectiveness of TC-based fall prevention interventions.

Keywords: Dynamic stability; Fall prevention; Feasible Stability Region; Tai Chi.

PMID: 33668007 DOI: 10.1016/j.gaitpost.2021.02.025