Characteristics of Stair Ascent in Patients with Knee Osteoarthritis

ABSTRACT

OBJECTIVE: To investigate the kinematic and kinetic characteristics of stair ascent in patients with knee osteoarthritis. METHOD: Twenty patients with knee osteoarthritis and twenty healthy controls were recruited. The kinematic and kinetic data were obtained through a three dimensional motion analyzer. The kinematic and kinetic data during stair ascent were compared between two groups. RESULTS: The total required time of stair ascent was significantly longer in the osteoarthritis group than that of the control group (p<0.05). In comparison with the control group, the angle of maximal pelvis anterior tilting, minimal and maximal hip flexion and minimal knee flexion were significantly increased (p<0.05). However, the angle of knee flexion and ankle dorsiflexion at initial contact were significantly decreased in the osteoarthritis group (p<0.05). The maximal moment and power of knee extension and ankle plantarflexion were significantly decreased in the osteoarthritis group (p<0.05). Sixteen patients (80.0%) in the osteoarthritis group showed flexion arc after initial contact. "W" sign was shown in 16 patients (80.0%). CONCLUSION: We found the unique kinematic and kinetic patterns during stair ascent in patients with knee osteoarthritis, and that knee osteoarthritis influence not only kinematic and kinetic patterns of knee but also those of hip and ankle.