Abnormalities of the First Three Steps of Gait Initiation in Patients with Parkinson's Disease with Freezing of Gait

Abstract

The purpose of this study was to investigate abnormalities of the first three steps of gait initiation in patients with Parkinson's disease (PD) with freezing of gait (FOG). Ten PD patients with FOG and 10 age-matched healthy controls performed self-generated gait initiation. The center of pressure (COP), heel contact positions, and spatiotemporal parameters were estimated from the vertical pressures on the surface of the force platform. The initial swing side of gait initiation was consistent among the trials in healthy controls but not among the trials in PD patients. The COP and the heel contact position deviated to the initial swing side during the first step, and the COP passed medial to each heel contact position during the first two steps in PD patients. Medial deviation of the COP from the first heel contact position had significant correlation with FOG questionnaire item 5. These findings indicate that weight shifting between the legs is abnormal and that medial deviation of the COP from the first heel contact position sensitively reflects the severity of FOG during the first three steps of gait initiation in PD patients with FOG.

Variable Initial Swing Side and Prolonged Double Limb Support Represent Abnormalities of the First Three Steps of Gait Initiation in Patients with Parkinson’s Disease with Freezing of Gait

“…Furthermore, this finding was consistent with the finding in PD + FOG (Okada et al, 2011). Therefore, the decreased first COP peak displacement along the anteroposterior axis in PD + FOG likely reflects the abnormality of the postural phase of self-generated gait initiation in PD patients in general, but is not specifically related to FOG.…”

“… Mean (SE of mean) . Asterisks indicate significant difference between PD patients and Healthy controls . Daggers indicate significant correlation between the parameter in PD + FOG and FOGQ item 5 . The data in PD + FOG were cited from the previous study (Okada et al, 2011) .…”

Differences in corticospinal excitability to the biceps brachii between arm cycling and tonic contraction are not evident at the immediate onset of movement

“…Abnormalities of gait initiation in people with PD have been previously described. Okada et al (2011) demonstrated that the duration of the initial step in patients with PD is significantly longer compared to healthy controls. Interestingly, no differences in duration were observed in the subsequent steps, indicating that certain motor pathways affected by PD are specific to the initiation of movement but not the rhythmic motor output that follows.…”

“…Abnormalities of gait initiation in people with PD has been previously described. Okada et al (2011) examined several parameters in the first three steps of gait following gait initiation in people with and without PD. Measurements included step length, step width, step time and step velocity.…”

“…Providing indirect support for this idea are results from Parkinson's disease studies that have found abnormalities in the first step of gait initiation but not in subsequent steps (Okada et al 2011). These findings indicate that the initiation and steady-state phases of rhythmic motor outputs may be under different neural control.…”