Walking velocity and modified rivermead mobility index as discriminatory measures for functional ambulation classification of chronic stroke patients

Ji Young Lim; Seung Heon An; Dae-Sung Park

doi:10.1142/S1013702519500112

Walking velocity and modified rivermead mobility index as discriminatory measures for functional ambulation classification of chronic stroke patients

Hong Kong Physiother J. 2019 Dec;39(2):125-132. doi: 10.1142/S1013702519500112. Epub 2019 May 21.

Authors

Ji Young Lim^{1

2}, Seung Heon An³, Dae-Sung Park¹

Affiliations

¹ Department of Physical Therapy, Konyang University, Daejeon, Republic of Korea.
² General Graduate School of Medical Science, Konyang University, Daejeon, Republic of Korea.
³ Department of Physical Therapy, National Rehabilitation Hospital, Seoul, Republic of Korea.

Abstract

Background: The cut-off values of walking velocity and classification of functional mobility both have a role in clinical settings for assessing the walking function of stroke patients and setting rehabilitation goals and treatment plans.

Objective: The present study investigated whether the cut-off values of the modified Rivermead Mobility Index (mRMI) and walking velocity accurately differentiated the walking ability of stroke patients according to the modified Functional Ambulation Category (mFAC).

Methods: Eighty two chronic stroke patients were included in the study. The comfortable/maximum walking velocities and mRMI were used to measure the mobility outcomes of these patients. To compare the walking velocities and mRMI scores for each mFAC point, one-way analysis of variance and the post-hoc test using Scheffe's method were performed. The patients were categorized according to gait ability into either $mFAC = VII$ or mFAC $\leq$ VI group. The cut-off values for mRMI and walking velocities were calculated using a receiver-operating characteristic curve. The odds ratios of logistic regression analysis (Wald Forward) were analyzed to examine whether the cut-off values of walking velocity and mRMI can be utilized to differentiate functional walking levels.

Results: Except for mFACs III and IV, maximum walking velocity differed between mFAC IV and mFAC V $(p < 0.01)$ , between mFAC V and mFAC VI $(p < 0.001)$ , and between mFAC VI and mFAC VII $(p < 0.05)$ . The cut-off value of mRMI is $> 26.5$ and the area under the curve is 0.87, respectively; the cut-off value for comfortable walking velocity is $> 0.77$ m/s and the area under the curve is 0.92, respectively; also, the cut-off value for maximum walking velocity is $> 0.92$ m/s and the area under the curve is 0.97, respectively. In the logistic regression analysis, the maximum walking velocity $(> 0.92$ m/s, $OR = 22.027)$ and mRMI $(> 26.5$ scores, $OR = 10.283)$ are able to distinguish $mFAC = VII$ from mFAC $\leq$ VI.

Conclusion: The cut-off values of maximum walking velocity and mRMI are recommended as useful outcome measures for assessing ambulation levels in chronic stroke patients during rehabilitation.

Keywords: Discriminatory factors; modified Functional Ambulation Category; modified Rivermead Mobility Index; stroke; walking speed.