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

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 1808 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.