Assessment of postural instability in patients with Parkinson’s disease
- 966 Downloads
Postural instability is one of the most disabling features of idiopathic Parkinson’s disease (PD). In this study, we focused on postural instability as the main factor predisposing parkinsonians to falls. For this purpose, changes in sway characteristics during quiet stance due to visual feedback exclusion were studied. We searched for postural sway measures that could be potential discriminators for an increased fall risk. A group of 110 subjects: 55 parkinsonians (Hoehn and Yahr: 1–3), and 55 age-matched healthy volunteers participated in the experiment. Their spontaneous sway characteristics while standing quiet with eyes open and eyes closed were analyzed. We found that an increased mediolateral sway and sway area while standing with eyes closed are characteristic of parkinsonian postural instability and may serve to quantify well a tendency to fall. These sway indices significantly correlated with disease severity rated both by the Hoehn and Yahr scale as well as by the Motor Section of the UPDRS. A forward shift of a mean COP position in parkinsonians which reflects their flexed posture was also significantly greater to compare with the elderly subjects and exhibited a high sensitivity to visual conditions. Both groups of postural sway abnormalities identified here may be used as accessible and reliable measures which allow for quantitative assessment of postural instability in Parkinson’s disease.
KeywordsParkinson’s disease Elderly Posture Balance Postural stability Falls
Gratitude is extended to Katrina R. Piskorski for her great assistance. The research was supported by the grant 2P05D 069 27 from the Polish Ministry of Science and Higher Education.
- Blaszczyk JW, Lowe DL, Hansen PD (1992) A heuristic model of postural stability. In: Woollacott M, Horak F (eds) Posture and gait: control mechanisms vol. II. University of Oregon Book, Portland, pp 228–231Google Scholar
- Duncan PW, Weiner DK, Chandler JM, Studenski SA (1990) Functional reach: a new clinical measure of balance. J Gerontol 45:192–197Google Scholar
- Maki BE, Holliday PJ, Topper AKA (1996) Prospective study of postural balance and risk of falling in an ambulatory and independent elderly population. J Gerontol 49:M72–84Google Scholar
- Takagi A, Fujimura E, Suehiro S (1985) A new method of statokinesogram area measurement: application of a statistically calculated ellipse. In: Igarashi S, Black FA (eds) Vestibular, visual control on posture and equilibrium. Karger, Basel, pp 74–79Google Scholar
- Winter DA (1995) A.B.C. anatomy, biomechanics and control of balance during standing and walking. Waterloo, Ontario, pp. 1–55Google Scholar