[Purpose] Medial knee osteoarthritis, a degenerative joint disease, affects adults. The
external knee adduction moment, a surrogate knee-loading measure, has clinical
implications for knee osteoarthritis patients. Tai Chi is a promising intervention for
pain alleviation in knee osteoarthritis; however, the characteristics of external knee
adduction moment during Tai Chi have not been established. [Subjects and Methods] During
normal and Tai Chi walking, a gait analysis was performed to compare the external knee
adduction moment moment-arm characteristics and paired t-tests to compare moment-arm
magnitudes. [Results] A significant difference was observed in the average lateral
direction of moment-arm magnitude during Tai Chi walking (−0.0239 ± 0.011 m) compared to
that during normal walking (−0.0057 ± 0.004 m). No significant difference was found
between conditions in average medial direction of moment-arm magnitude (normal walking:
0.0143 ± 0.010 m; Tai Chi walking: 0.0098 ± 0.014 m). [Conclusion] Tai Chi walking
produced a larger peak lateral moment-arm value than normal walking during the stance
phase, whereas Tai Chi walking and normal walking peak medial moment-arm values were
similar, suggesting that medial knee joint loading may be avoided during Tai Chi
walking.