Objective measurement of motor disability in Parkinson's disease.

A kinesiological analysis of complex movement performance was carried out in patients with Parkinson's disease, and in healthy subjects of different ages, with a computer-assisted optoelectronic camera system. A lifting movement entailing simultaneous coordination of rising, walking some steps and a goal-directed manual movement, the PLM test, was used. Speed reduction through normal aging was greatest at higher ages, where the coordination deficits were also most prominent. The increased movement time in parkinsonian patients was due both to deficient simultaneous coordination of postural, locomotor and manual movement phases, and to varying increases in phase durations. It was possible to determine postural, locomotor and manual disability profiles quantitatively, in terms of the relative phase time values. The presented documentation of parkinsonian disability and single-dose effects of l-dopa indicates that the technique is applicable in the objective assessment of disability and pharmacotherapeutic efficacy.