Analysis of Ground Reaction Force During Ascending and Descending Staircases of Varying Heights in Persons with Knee Osteoarthritis

This study attempted to clarify this controversy and to investigate the differences in GRFs between persons with KOA and healthy controls matched for age, weight, height, and walking velocity during stair negotiations. 

Fifteen persons with KOA (K/L grade II) and fifteen healthy controls were recruited in this study. All participants needed to walk through a level surface, ascended and descended a stair at three different heights (180, 210, and 240 millimeters). The leading leg’s GRFs (V: vertical, AP: anterior-posterior, ML: medial-lateral directions, 1: weight acceptance phase, 2: pushing-off phase) were recorded by a force plate, placing in front of the staircase. A mixed two-way repeated ANOVA measure was used to identify the interactions between the effects of KOA and the effects of heights of staircase. 

A significant interaction between the effect of KOA and the effect of heights of staircase was found in the V2 (p 0.001), in the AP1 (p = 0.003), in the ML1 (p = 0.019), in the ML2 (p = 0.046), and Time to V1 (p = 0.003). V2 and AP1 peaks were significantly lower in persons with KOA than in controls while walking on level surface and stair ascent. While performing stair descent, persons with KOA demonstrated significantly a lower ML1 but a greater ML2 compared with controls. In addition, the V1 was reached earlier in the stance phase in persons with KOA than in controls during the stair descent.

This study demonstrated differences in GRF peaks and the time to peaks during ascent and descent of a staircase in persons with KOA compared to controls.

Persons with KOA demonstrated a conservative control mechanism during stair negotiation, especially when descending stairs. Consequently, it is advisable for rehabilitation practitioners to provide additional attention and comprehensive training for KOA persons who require regular ascending or descending high staircases in their daily life. Additionally, future study may apply the challenging task as an intervention to determine whether repetition of challenging stair negotiation improves gait stability and further reduces the risk of falling.