Enhancing Mobility for Lower Limb Amputees
Submitting Institution
Roehampton UniversityUnit of Assessment
Allied Health Professions, Dentistry, Nursing and PharmacySummary Impact Type
TechnologicalResearch Subject Area(s)
Medical and Health Sciences: Clinical Sciences, Human Movement and Sports Science
Summary of the impact
This case study examines the long-term and ongoing relationship between
an industrial collaborator (Chas A Blatchford & Sons Ltd) and
researchers at the University of Roehampton. This systematic programme of
biomechanical research on how prostheses perform in activities other than
walking has had two significant outcomes. Firstly, this work has
significantly improved prosthetic design, with four new prosthetic designs
marketed worldwide. Secondly, it has increased awareness of — and
importantly increased engagement with - exercise therapy for amputees
among healthcare professionals (prosthetists and physiotherapists) and
amputees themselves. This research has reached a wider audience including
amputee charities and healthcare professionals, with whom we focus on
mobility and movement rather than the prostheses.
Underpinning research
The research underpinning this case study has been led by Dr Siobhan
Strike, Principal Lecturer at the University of Roehampton (from 2000),
with ongoing contributions from Dr Ceri Diss, Senior Lecturer (from 2007)
and Marlene Schoeman, Roehampton PhD Student (2007-2011) now at the
University of the Free State, South Africa, Dr Natalie Vanicek (from 2006)
initially at the University of Hull, now at the University of Sydney, and
Dr Matthew Taylor, Roehampton PhD Student (2002-2008), now at the
University of Essex.
Following a preliminary stage of research into biomechanics and
prosthetics, a programme of research explicitly exploring the
rehabilitation of lower limb amputees began in 2008, with the overarching
goal of improving the functional mobility of these individuals. The
specific aim of this programme was to monitor the mechanisms by which
amputees achieve movement whilst compensating for their prosthetic limb.
The movements studied were selected to represent daily living and
exercise:
- rapid and high loading activities (running, jumping, stair descent)
- torsion activities (steering, turning)
- basic mobility (steady-state walking and stair ascent)
The findings revealed a number of mechanisms that affect amputees'
ability to run, turn and jump (Schoeman et al., 2012; Strike & Taylor,
2009; Strike et al., 2012). In a study on movement asymmetry and
compensations that occur when performing a countermovement vertical jump,
Schoeman et al. (2012) reported high loading on the intact side and a poor
contribution by the prosthetic side. Examination of running extended the
previous study by exploring the mechanisms to absorb loads during the
impact phase, the latter being related to long-term injury to the
musculoskeletal system. We demonstrated that a shock-absorbing device
developed to protect the residual limb was not consistently effective in
this phase. These findings suggest that practitioners should be cautious
in prescribing high-impact exercises such as jumping and running as these
exert large forces on the intact and residual limbs, especially for those
who have a high level of asymmetry between limbs and low strength around
the hip joint. In preparation for exercise, amputees should engage in
balance and strength-based low-impact exercises to improve their
functioning mobility and reduce the likelihood of injury and chronic
damage in sport and exercise. Research is ongoing with the prosthetic limb
manufacturer (Chas A Blatchford & Sons Ltd) to enhance the
shock-absorbing capacity of the prosthetic limb to optimise performance.
Research has also focussed on falling among lower limb amputees, as this
is an issue of great concern for amputees and health care professionals.
When assessing the biomechanical differences between amputees who fall and
those who do not, we observed that amputees who have a history of falling
complete movements more quickly and have reduced knee and hip strength
when walking or negotiating stairs (Vanecik et al., 2009a,b). They also
demonstrate poor postural awareness. We highlighted the limitations of
current clinical measures used by healthcare professionals for monitoring
fall risk, fall incidence and self-perceived quality of life. Consequently
the professional organisation associated with physiotherapy in amputees,
the British Association of Chartered Physiotherapists in Amputee
Rehabilitation (BACPAR), has begun a research programme into the
monitoring and reporting of falls for amputees. A significant part of our
work was performed in partnership with Chas A Blatchford & Sons Ltd,
which is a leading worldwide prosthetic and orthotics company. They
supported our research, providing resources `in kind' through professional
fitting and components, and facilitated MSc and PhD research (by Taylor
and Schoeman, respectively).
References to the research
3. Strike SC, Taylor, MJD (2009) The temporal-spatial and ground reaction
impulses of turning gait: Is turning symmetrical? Gait & Posture 29,
597-602. doi: 10.1016/j.gaitpost.2008.12.015.
4. Vanicek N, Strike S, McNaughton L, Polman R (2009a) Postural responses
to dynamic perturbations in amputee fallers vs. non-fallers: a comparative
study with able-bodied subjects. Archives of Physical Medicine &
Rehabilitation 90, 1018-1025. DOI: 10.1016/j.apmr.2008.12.024
5. Vanicek N, Strike S, McNaughton L, Polman R (2009b) Gait patterns in
transtibial amputee fallers vs. non-fallers: biomechanical differences
during level walking. Gait and Posture 29, 415-420. DOI:
10.1016/j.gaitpost.2008.10.062
All outputs have been through rigorous peer-review, and the research was
supported by £3,000 of funding from the Owen Shaw Fund of the Circulation
Foundation to explore the biomechanics of standing turns in transtibial
amputees in 2007.
Details of the impact
This systematic programme of research is the first to explore how
prostheses interact with functional mobility among amputees during
activities other than walking. The research is furthering our knowledge
and understanding of how amputees turn, negotiate stairs, jump and run,
and is having a significant impact in two areas:
Impact 1: Improved prosthetic design by a leading prosthetic limb
manufacturer
Our research has led to clear indications of the limitations of
prostheses and the pathomechanics adopted by amputees. Identified
adaptations which compensate for the lost function include the altered
motion at the ankle, the reduced involvement at the residual knee, the
compensatory role of the residual hip and the implications for the intact
limb. The inability of the prosthetic ankle to function effectively and to
allow the foot complex to absorb and return energy efficiently, both in
terms of the magnitude and timing, was first identified very early in the
programme of research (Strike and Hillery, 2000). Continuing this
research, but focussing on recreational rather than elite athlete
amputees, enabled identification of other activities that have been
analysed in collaboration with our industrial partner (Blatchford). The
research using the `Tele Torsion' device, developed to absorb vertical and
rotational shock, indicated that this device produced energy efficiencies
in turning activities, and it was marketed worldwide on this basis. The
findings fed into the development of the `TT Pro' prosthesis, which had
altered twisting angles and torsion resistance to more closely reflect the
requirements of human movement. The research on dynamic activities
increased our knowledge of amputee movement patterns in sport, and in turn
into design requirements of the `Elite VT', `Echelon VT' and the
forthcoming `Elan VT' prosthetic feet/ankle complex to enhance their shock
absorption capacity. The intention behind the design modifications is to
adapt the magnitude and frequency of the forces and moments generated
externally. Most recently, the research has highlighted the different
requirements of prostheses across a range of movement types including
running, walking, standing and cornering. This research is feeding into
the development of a new product by Blatchford, the `Blade XT', which aims
to enable more amputees to participate in exercise. This research approach
has enabled the facility to become an internationally renowned centre
specialising in amputees and exercise, and with unique experience and
expertise in amputee turning and rotational biomechanics.
Impact 2: Raising Amputee and Practitioner Awareness of Exercise
Therapy
In order to raise amputees' and practitioners' awareness of the role of
exercise therapy for both recreationally active amputees and those who are
fallers, a number of strategies were implemented. First, the research
findings were fed back to the participants and the professional
organisations involved (i.e. Blatchford, Clinical Provision), who in turn
informed their colleagues. Second, to reach a wider audience, the authors
published the findings in professional practice outlets, including
non-peer reviewed articles for BACPAR (2011), a book chapter in Ergonomics
for Rehabilitation Professionals (2009) and presentations and
conferences for prosthetists through the International Society for
Prosthetics and Orthotics (presentations at the ISPO triennial conference
over the period) and study days (Royal Free Hospital and BACPAR).
To raise the awareness of the role of exercise therapy for amputees, and
the need to engage safely in exercise, the University of Roehampton sought
collaboration with Limbpower (a leading amputee charity) to promote
effective participation in prescribed exercise to improve functional
ability. Following a number of in-depth discussions with the charity, it
was decided that producing a DVD would provide the most effective resource
for amputees to observe and learn the evidence-based exercises safely and
with maximum benefits, whilst avoiding potential long-term damage. The
specific exercises are aimed to improve balance and proprioception and,
particularly, to enable effective use of the hip musculature. The
exercises are demonstrated and performed by amputees, with key pointers to
ensure correct execution. The research-informed DVD has impacted on the
reach of the charity by contributing to and complementing their expertise,
and lends weight to the advice and support they give in reaching out to
new amputees and encouraging them to exercise.
To evaluate the effectiveness of the DVD, feedback from the charity and
the amputees themselves was sought. Amputees identified that the DVD gave
them a good place to start exercising and removed the fear around
beginning dynamic movement, which they felt might break their prosthesis
or injure their intact limb and joints. Amputees also indicated that it
was exactly what was needed to point them to a starting place for exercise
and that it allowed them to move beyond basic rehabilitation administered
in the limb fitting centres. In turn, this resulted in the research team
running sessions at the Amputee Games (May 2013), where they met with the
amputees, discussed their research, and evaluated the effectiveness of the
DVD, receiving feedback and positive comments. Following the success of
the DVD with the amputees at the games, another leading charity — The
Limbless Association — has invited us to publish an article about it in a
forthcoming newsletter, which has several hundred subscribers.
Sources to corroborate the impact
- Saeed Zahedi, Technical Director of Chas A Blatchford and Sons Ltd.
(Identifier 1).
- Kiera Roche, Limbpower (Identifier 2).
- DVD materials and magazine articles developed in collaboration with
Limbpower.
- E-mail feedback from users of DVD. (Identifier 3 & 4).
- http://amputeerunningdiary.wordpress.com
-
Falls efficacy, health
status and functional performance in trans-tibial amputee fallers vs.
non-fallers BACPAR Journal (27/3/12).
-
Gait and Ergonomics: Normal and Pathological in Ergonomics for
Rehabilitation Professionals edited by Shrawan Kumar (2009) CRC
Press.