A custom designed Virtual Gait Retraining System (VGRS) is being adapted for balance and
mobility rehabilitation in individuals with transtibial amputation. The system is composed
of a treadmill that can simulate different environmental situations such as walking up
stairs and hills and going around curves. The treadmill is synchronized with an immersive
display and an avatar of the user. The combination of variable terrain and visual feedback
is extremely promising as a means for amputee patients to achieve improved functional
mobility after gait training. The proposed work is relevant to public health because it is
the first step in developing a novel rehabilitation system that will use visual feedback for
gait training in amputees and others with pathological gait disorders. The research is
pertinent to the mission of the Department of Veterans Affairs which is committed to improve
the quality of life of Veterans with disability.
Lower extremity amputation can cause impairments in gait and balance due to the loss of
proprioception and motor control. The asymmetries present during amputee gait are thought to
be one of the major contributors to secondary musculoskeletal problems such as
osteoarthritis. After lower extremity amputation, physical rehabilitation is necessary to
achieve functional ambulation; however, no an evidence-based standard of care exists for
individuals who undergo transtibial (TT) amputations. The objective of this application is
to determine the effectiveness of gait training in an immersive virtual environment in
people with transtibial amputation. The investigators' custom designed Virtual Gait
Retraining System (VGRS) is a virtual reality (VR) system which provides visual and motor
challenges while treadmill walking. The VGRS immerses the user in a virtual world, provides
additional feedback with an avatar and presents the user with challenging tasks such as
inclines and stair climbing which are complemented by the movement of the treadmill. The
central hypothesis is that people with amputations will achieve greater improvements in
balance, mobility and gait function using the investigators' custom designed VGRS as
compared to current conventional treadmill gait training. This objective will be
accomplished by addressing the following specific aims:
- 1) Compare the efficacy of VGRS to conventional treadmill training.
- 2) Evaluate the rate of improvement over the course of each training program (VGRS and
The investigators will conduct a randomized clinical trial with twenty TT amputee subjects
comparing 6 weeks of training with the VGRS to 6 weeks of training using a conventional
treadmill protocol. The investigators will use gait analysis, postural sway and standard
balance and mobility instruments including the 6-Minute Walk Test, Four Square Step Test,
the Berg Balance Scale and the Dynamic Gait Index to assess improvements in gait and
mobility. The investigators will evaluate subject pre- and post training and at an interim
point 3 weeks into the training sessions. The investigators anticipate that the VGRS will
deliver more effective training by creating a realistic and challenging environment with
accurate visual perception of a motor task which is being simultaneously performed by the
user. The investigators will also gain an understanding of the rate of improvement for TT
amputees during treadmill training. The research design will demonstrate the need for
immersive virtual reality that includes a rich visual display and affords the opportunity to
train on a variety of terrain conditions and mobility tasks.
- Subjects must be unilateral transtibial amputees (TTA) between the ages of 18 and 65
who have consistently used a prosthesis for at least one year.
- Subjects must be community ambulators at a K3 level,
- which dictates that they have the ability or potential to walk with variable
- to traverse most environmental barriers and may have vocational, therapeutic, or
exercise activity that demands prosthetic utilization beyond simple locomotion.
- History of surgical procedures on their intact limb.
- Subjects will be excluded from the study if they present with
- or balance disorders that can affect gait.
- Rheumatoid arthritis,
- knee joint replacement,
- and the use of ambulatory aids will also exclude participation.
- Subjects with considerable pain in their knee joints, as measured by a visual analog
scale will also be excluded due to the confounding effects of pain on gait patterns.
- A medical history screening will be used to identify subjects with pre-existing
conditions that would compromise their gait.
Susan E D'Andrea, PhD MS BS
Providence VA Medical Center, Providence, RI