The effect of bilateral knee osteoarthritis on spatiotemporal gait parameters during incline walking: implications for gait rehabilitation.

Bilateral KOA patients had significantly shorter step and stride lengths compared to healthy controls at all inclines, even after controlling for walking speed.

• Fifteen bilateral KOA patients and fifteen healthy controls were recruited and walked on a treadmill at five inclines (+6%, +3%, 0%, -3%, and -6%).
• A mixed two-way repeated measures ANCOVA was used with walking speed as a covariate.
• Shorter step and stride lengths were observed in KOA patients across all incline conditions despite speed being controlled.
• WOMAC physical function scores correlated negatively with step and stride length.

Bilateral KOA patients had longer double support times compared to healthy controls, predominantly during downhill walking.

• Double support time differences were significant in the group-by-incline interaction revealed by ANCOVA.
• Longer double support times were predominantly observed during downhill inclines (-3% and -6%).
• WOMAC physical function scores correlated positively with double support time.
• Prolonged double support time was interpreted as a stability and load distribution strategy.

KOA patients exhibited a significant quadratic U-shaped trend in gait variability across inclines, while healthy controls showed a linear decrease in variability as incline increased.

• Gait variability in KOA patients increased during both uphill and downhill walking, forming a U-shaped quadratic trend.
• In contrast, gait variability in healthy controls linearly decreased as incline increased.
• This distinct pattern of variability modulation was described as 'a novel adaptive motor control strategy for managing the mechanical demands of inclined surfaces.'
• The group-by-incline interaction for gait variability was identified as significant in the ANCOVA.

WOMAC physical function scores were significantly correlated with spatiotemporal gait parameters in bilateral KOA patients.

• Pearson correlations were used to assess relationships between WOMAC scores and spatiotemporal parameters.
• WOMAC physical function correlated positively with double support time.
• WOMAC physical function correlated negatively with step length and stride length.
• These correlations indicate that greater self-reported physical dysfunction is associated with more altered gait patterns.

A significant group-by-incline interaction was found for several spatiotemporal gait parameters between bilateral KOA patients and healthy controls.

• The study used a mixed two-way repeated measures ANCOVA with walking speed as a covariate to control for the known slower walking speed in KOA patients.
• Five incline conditions were tested: +6%, +3%, 0%, -3%, and -6%.
• Gait parameters were collected using a three-dimensional motion analysis system during treadmill walking at self-selected speed.
• The significant group-by-incline interaction indicated that KOA patients and healthy controls adapted differently to changing inclines.

There is a paucity of research examining how bilateral KOA patients adapt to incline walking despite it being a common real-world activity.

• Gait alterations in KOA patients during level walking are well documented, but incline walking has received less attention.
• KOA patients typically walk slower than healthy adults, making it essential to control for walking speed when comparing gait parameters.
• The study specifically focused on bilateral KOA to address this gap, recruiting 15 KOA patients and 15 healthy controls.
• The findings were noted to have implications for rehabilitation of downhill walking in KOA patients.