Mobility Lab to Assess Balance and Gait with Synchronized Body-worn Sensors

Abstract

This paper is a commentary to introduce how rehabilitation professionals can use a new, body-worn sensor system to obtain objective measures of balance and gait. Current assessments of balance and gait in clinical rehabilitation are largely limited to subjective scales, simple stop-watch measures, or complex, expensive machines not practical or largely available. Although accelerometers and gyroscopes have been shown to accurately quantify many aspects of gait and balance kinematics, only recently a comprehensive, portable system has become available for clinicians. By measuring body motion during tests that clinicians are already performing, such as the Timed Up and Go test (TUG) and the Clinical Test of Sensory Integration for Balance (CITSIB), the additional time for assessment is minimal. By providing instant analysis of balance and gait and comparing a patient's performance to age-matched control values, therapists receive an objective, sensitive screening profile of balance and gait strategies. This motion screening profile can be used to identify mild abnormalities not obvious with traditional clinical testing, measure small changes due to rehabilitation, and design customized rehabilitation programs for each individual's specific balance and gait deficits.

Conflict of interest statement

Competing interests

Drs. Salarian, Holmstrom, McNames and Horak have significant financial interests in APDM, a company that has a commercial interest in the results of this research and technology. This potential conflict of interest has been reviewed and managed by OHSU and the Integrity Oversight Council.

Figures

Figure 1

A. Sensor dimension B. Mobility Lab system and components

Figure 2

Five Opals applied to the body (ankles, wrists and lumbar) during the turning of the iTUG test.

Figure 3

Components and metrics of ISAW, ITUG, ISWAY and ISTEP.

Figure 4

Example of the MobilityLab report Left panel: first page. Right panel: ISAW primary measures for 3 subsequent test in a PD patient, first test OFF Med OFF DBS, then OFF Med ON DBS, and ON Med ON DBS.

Figure 5

Raw signals from lower back and ankle sensors during ISAW

Figure 6

SRM of objective and clinical measures for the exercise study

Figure 7

A. Acceleration signals recorded from the Lumbar sensor during 30 s of quiet stance. Examples in a representative control, PD and MS subjects. B. Trunk Rotation Range of Motion during gait. Means+SEM are showed in 12 control, 12 untreated PD, and 31 early MS. Adapted from Zampieri et al, Spain et al. [24, 25].