Developing methods to evaluate how people with Parkinson's Disease turn 180 degrees: an activity frequently associated with falls

Abstract

Purpose: To develop a test that identified fallers from their turning strategies, as people with Parkinson's Disease (PD) commonly fall turning.

Method: We compared (1) Turn Types demonstrated when turning 180 degrees during the Timed Up and Go Test (TUG Test) by 19 non-fallers and 29 fallers (median age 71) and (2) Turn Types, Turning Steps, Heelstrike, Stability and the Use of Space and Support demonstrated when turning 180 degrees during an everyday activity by 15 non-fallers and 26 fallers (median age 75). Turns were rated from video by observers blinded to group. Inter-observer agreement was tested.

Results: Similar proportions of fallers and non-fallers demonstrated multiple-step Turn Types during the TUG Test (69% v 58%; p=0.433) and the everyday activity (66% vs. 46%; p=0.241). When turning, similar proportions of each group lacked Heelstrike, lost Stability and used the available Space and Support (p>0.7); Turning Step counts were also similar (p=0.891). Inter-observer agreement proved acceptable except for Turn Type during everyday activity (Kappa=0.46).

Conclusions: The anticipated differences between fallers and non-fallers were not identified, perhaps obscured by insufficiently or overly challenging protocols and/or the compensations deployed by fallers. Further methodological development is needed in the analysis of fall-related activities with high-risk groups.