L Test Subtask Segmentation for Lower-Limb Amputees Using a Random Forest Algorithm.

Journal: Sensors (Basel, Switzerland)
PMID:

Abstract

Functional mobility tests, such as the L test of functional mobility, are recommended to provide clinicians with information regarding the mobility progress of lower-limb amputees. Smartphone inertial sensors have been used to perform subtask segmentation on functional mobility tests, providing further clinically useful measures such as fall risk. However, L test subtask segmentation rule-based algorithms developed for able-bodied individuals have not produced sufficiently acceptable results when tested with lower-limb amputee data. In this paper, a random forest machine learning model was trained to segment subtasks of the L test for application to lower-limb amputees. The model was trained with 105 trials completed by able-bodied participants and 25 trials completed by lower-limb amputee participants and tested using a leave-one-out method with lower-limb amputees. This algorithm successfully classified subtasks within a one-foot strike for most lower-limb amputee participants. The algorithm produced acceptable results to enhance clinician understanding of a person's mobility status (>85% accuracy, >75% sensitivity, >95% specificity).

Authors

  • Alexis L McCreath Frangakis
    Department of Mechanical Engineering, Faculty of Engineering, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
  • Edward D Lemaire
    a Centre for Rehab Research and Development , Ottawa Hospital Research Institute , Ottawa , Canada.
  • Helena Burger
    University Rehabilitation Institute, Ljubljana, Slovenia.
  • Natalie Baddour
    f Department of Mechanical Engineering , University of Ottawa , Ottawa , Canada.