Gait quantitation in Parkinson's disease--locomotor disability and correlation to clinical rating scales.

Stride parameters were established in 17 patients with idiopathic Parkinson's disease (PD; mean age 68.8 yrs.; Hoehn-Yahr stages 2 and 3) and in 33 healthy age-matched controls. Free-walking speed was lower in PD as were stride length and cadence. Impaired locomotor synergies in PD were reflected by a higher coefficient of variation of stride length; step width and its coefficient of variation (the latter related to postural imbalance in locomotion) were not changed. No stride parameter correlated with any total score of either the Hoehn-Yahr Scale, the Unified Parkinson's Disease Rating Scale Motor Examination ("UPDRS-III"), the Columbia Rating Scale (CURS) or the Webster Rating Scale. Stride length correlated with a CURS-Bradykinesia-Score, whereas gait velocity correlated with UPDRS-III-Axial-Motor-Score and with the CURS-Bradykinesia-Score. Hypokinesia of gait in moderately disabled PD patients is best assessed by combined analysis of stride parameters and locomotion-related subscores from conventional rating scales.