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Task-Oriented Ankle and Foot Training for Improving Gait, Balance, and
Strength in Individuals with Multiple Sclerosis: A Pilot Study


Cizelle Rodriques MS1, Kurt Jackson PhD2, Joaquin Barrios PhD2, Lloyd
Laubach PhD1, Kimberly Edginton-Bigelow PhD3

1Department of Health and Sport Science, University of Dayton, Dayton,
Ohio, USA, 2Department of Physical Therapy, University of Dayton, Dayton,
Ohio, USA, 3Department of Mechanical and Aerospace Engineering, University
of Dayton, Dayton, Ohio, USA


ABSTRACT


Rodrigues C, Jackson K, Barrios J, Laubach L, Edginton-Bigelow K. Task-
Oriented Ankle and Foot Training for Improving Gait, Balance, and Strength
in Individuals with Multiple Sclerosis: A Pilot Study. JEMonline
2016;1(1):1-13. The purpose of this pilot study was to investigate the
effects and feasibility of a task-oriented ankle and foot exercise program
on gait, balance, and strength in 6 adults with mild to moderate disability
from multiple sclerosis (MS). The subjects participated in an 8-wk task-
specific home-based ankle and foot exercise program. Outcome measures
included stance phase ankle joint torque and power, limits of stability,
isometric and isokinetic ankle strength, gait speed, and the 12-item
Multiple Sclerosis Walking Scale (MSWS-12). Five subjects completed the 8-
wk intervention. Following training, there were significant increases in
ankle power during early (38.1%) and late (11.8%) stance, limits of
stability (6.1%), and isokinetic dorsiflexion (26.4%), and plantar flexion
(15.0%) strength. There were no differences in isometric strength, gait
speed, or the MSWS-12. The findings indicate that a task-oriented home-
based ankle and foot exercise program appears to be safe and feasible and
may improve select measures of gait, balance, and muscle performance in
individuals with MS who have mild to moderate disability. Further research
may be warranted.

Key Words: Ankle, Exercise, Task-oriented, Multiple sclerosis


INTRODUCTION

Multiple sclerosis (MS) is a chronic, progressive disease of the central
nervous system characterized by inflammation and demyelination of axons
within the brain and spinal cord (12). Individuals with MS often experience
problems with gait, balance, and functional activities due to the combined
effects of muscle weakness, sensory loss, spasticity, and fatigue (21).
Gait and balance disturbances are common and can affect over 80% of people
with MS (25). Impairments in gait can have a significant impact on
activities of daily living and social participation, and are perceived by
patients to be one of the most important factors influencing quality of
life (6,27). People with MS also exhibit impaired postural control and
balance across various environmental and behavior conditions including
stance under altered sensory conditions, limits of stability and reactive
postural responses to an unexpected loss of balance (3).

Weakness in the muscles of the legs is a common impairment seen in people
with MS (15,23,24), and is considered an important factor in the
development of both gait and balance deficits (2,28). In studies of healthy
adults, the power generated by the ankle plantar flexors during gait has
been shown to be an essential contributor to forward propulsion (9) and
distal lower extremity muscles play an important role in basic balance
reactions such as ankle strategies (22). Although evidence suggests that
resistance training is well tolerated and can improve muscle strength in
MS, there is less convincing evidence that it can improve specific
components of gait, balance, and functional capacity (16). To date, most
strength training studies for individuals with MS have employed more
traditional machine based resistance exercises that focus on isolated
muscles that involve slower muscle contractions performed in less than
optimal functional positions (18). Additionally, most exercise training
studies for MS subjects have been multi-modal in nature with some
combination of strength, flexibility, and endurance training that makes it
more difficult to identify which specific exercises may have been most
beneficial (18). Identifying the most effective exercises is important for
people with MS because fatigue may limit tolerance to the number and type
of exercises that can be performed in a given session (8). Also, due to the
chronic nature of MS, finding effective exercises that can be performed
safely in the home or community setting on a long-term basis is also an
important consideration.

Therefore, the primary purpose of this pilot study was to measure the
effects of a simple task-oriented home based ankle and foot exercise
program on gait, balance, and strength in adults with MS. Additionally, we
hoped to assess the feasibility of the exercise program and use the
findings to assist in the planning of future trials.

METHODS

Participants
Six subjects were recruited using a database of individuals with MS who had
participated in prior unrelated research at the University of Dayton and
through informational fliers distributed to local health care providers.
The inclusion criteria included: (a) diagnosis of relapsing-remitting or
secondary progressive MS; (b) stable on current medications for at least 4
wks; (c) able to ambulate a minimum of 10 m without an assistive device or
physical assistance of another person; and (d) currently not participating
in any regular strength or balance training program. Subjects were excluded
from the study if they had any other neurological condition, had
cardiovascular, orthopedic, and/or metabolic conditions that would make the
exercise training unsafe, or had an exacerbation of their MS in the last 60
d. All subjects gave informed consent that was approved by the
Institutional Review Boards at the University of Dayton. Characteristics of
the 5 subjects who completed the study are presented in Table 1.

Table 1. Participant Characteristics.
|Characteri|Participant|Participant 2 |Participant 3 |
|stic |1 | | |
|Marching |1-3 min |Increase speed and time (max of 3 |Warm-up activity |
| | |min) as tolerated with use of hand |to increase |
| | |hold support as needed |circulation and |
| | | |motor activity. |
|Heel Raise|2 sets |Level 1: Stride stance position with|Increase power |
| |10-15 reps |weight shifted toward back foot. ^ |during push-off |
| | |speed as tolerated. |phase of gait. |
| | |Level 2: Front foot on 8 inch step | |
| | |with weight shifted toward back | |
| | |foot. ^ speed as tolerated. | |
| | |Level 3: Front foot on 8 inch step | |
| | |with weight shifted toward back foot| |
| | |with adjustable ankle weight (1-5 | |
| | |lbs) around back foot. ^ speed as | |
| | |tolerated. | |
|Toe |2 sets |Toe raises in stride stance using |Improve ankle |
|Raise |10-15 reps |board and resistance bands. Subjects|control during |
| | |progressed through the following |loading response. |
| | |levels of resistance bands with ^ | |
| | |speed as tolerated: yellow> red> | |
| | |green> blue. | |
|Gastroc |2 x 30 sec |Using a plastic wedge, increase |Increase |
|Stretch | |stretch as tolerated. |dorsiflexion ROM |
| | | |to allow tibial |
| | | |progression during|
| | | |stance and |
| | | |increase anterior |
| | | |limits of |
| | | |stability. |


*All exercises performed 2 x wk for 8 wks with 48 hrs between exercise
bouts.
























Figure 2. A, Level 1 heel raise; B, Level 2 heel raise with front foot on
8" step; C, Level 3 heel raise with step and ankle weight; D, start
position for toe raises; E, end position for toe raise; F, wedge stretch
for gastrocnemius.

The 8-wk home-based exercise program focused on ankle and foot strength,
power, and flexibility. It was designed to be task-oriented by mimicking
the position of the lower extremity during the loading response and push-
off phases of gait. The exercises were performed twice weekly on both lower
extremities with at least 48 hrs between exercise bouts. The subjects were
instructed to perform all exercises in a corner of a room with chairs on
either side for balance, but were encouraged to minimize use of upper
extremity support. The exercises included a brief warm-up of marching in
place, which was followed by progressively challenging heel and toe raises
that were performed in a stride stance position and concluded with a
gastrocne