BACKGROUND: The effect of levodopa on the gait of Parkinson's disease (PD) patients over unobstructed terrain is known, but little is known about its effect on gait over obstacles. OBJECTIVE: To describe the locomotor behavior of PD patients by means of kinematic tools and to verify their locomotor strategies during obstacle avoidance at different heights, with and without the effect of levodopa. METHOD: Five PD patients (Hoehn & Yahr= 2 ± 0; age= 68.4 ± 5.7 years old) walked 10m and stepped over one of two obstacles (high obstacle at half of knee height; low obstacle at ankle height) in two separate sessions: without medication (fasting) and at the peak of levodopa action. The following variables were collected and analyzed: foot placement prior to the obstacle (FPPO), leading toe clearance (LTCL), foot placement after the obstacle (FPAO) and horizontal and vertical mean velocities in the approach and landing phases (respectively, HVAP, VVAP, HVLP and VVLP). RESULTS: ANOVA by trials revealed that the main effects from the obstacle were on LTCL (F1.49= 15.33; p< 0.001), VVAP (F1.49= 82.184; p< 0.001), HVLP (F1.49= 15.33; p< 0.001) and VVLP (F1.49= 31.30; p< 0.001). Medication had its main effects on LTCL (F1.49= 6.66; p< 0.013) and VVAP (F1.49= 10.174; p< 0.002). CONCLUSION: Patients were more disturbed by the high obstacle. The PD symptoms (bradykinesia and hypokinesia) decreased under medication, as shown by increases in leading limb velocity and the safety margin over the obstacles. The patients presented gait patterns that ensured safety and stability, regardless of whether medicated or not.
Parkinson's disease; gait; levodopa; elderly; gait with obstacle
