JMIR Publications

ABSTRACT

Background:

Falls are a leading cause of injury among older adults, often resulting from dynamic balance disturbances. It is influenced by a dynamic and complex interplay of intrinsic and extrinsic fall risk factors. To identify individual fall risk, it is important to understand the underlying associations.

Objective:

The aim of this work was to build an experimental setup modeling selected factors leading to a loss of balance, measured by the Margin of Stability (MoS) in an ecologically valid real-world example (tripping). Additionally, these analyses aimed to assess the utility of the MoS as part of a prototypical dynamic fall risk model to differentiate between fall risk groups.

Methods:

Nineteen community-dwelling older adults (mean age 71 years; 37% women) completed the tripping protocol involving perturbations under various conditions. Clinical assessments were used to identify relevant fall-related intrinsic fall risk factors. MoS was measured using an eight-camera motion capture system. Receiver Operating Characteristic (ROC) analyses determined the ability of MoS to distinguish between low and high fall risk groups.

Results:

Perturbations significantly disrupted MoS, with a median MoS of -106.05 mm during the perturbed step compared to 114 mm in the pre-perturbation step. Recovery steps showed progressive stabilization, with the second recovery step achieving median MoS of 88.45 mm. The second recovery step exhibited the highest predictive accuracy for fall risk differentiation, with Area Under the Curve (AUC) values reaching 82.3% during slow walking with series of right-sided perturbations. In contrast, fast walking with random perturbations yielded lower AUC values (64.9%). Slow walking conditions generally demonstrated the clearest separation between fall risk groups.

Conclusions:

This study demonstrated the potential of MoS measurements during perturbations in predicting fall risk. Future studies should focus on expanding to frailer populations and additional fall scenarios for broader applicability. Clinical Trial: International Registered Report Identifier (IRRID): DERR1-10.2196/46930