An Introduction to
Podiatric Biomechanics
David N
Dunning
DipPodM. MChS.
MSc.
PGCert.(sports
pod)
Ancient history of Podiatry/Chiropody


The history of foot care
dates back as far as
walking upright.
“Man’s foot……is the most
distinctly human part of
the whole of his
anatomical make up….”
F Wood Jones (1949)
Socrates (471-401BC)

“To him whose feet
hurt everything
hurts”

To understand
nature we must first
try to understand
ourselves.
Hippocrates (460-370BC)
Not only is Hippocrates well
known for the oath but
also for emphasising
observation and
experience and for
rationalised science –
particularly in medicine.
He was also well known
for his work on Tyaloma
and Talipes.
Leonardo DaVinci (1452-1519)

“The foot is the most
marvellous of
machines – and a
work of art”

A great thinker,
mathematician, inventor,
military and civil engineer,
anatomist and dreamer. He
needed to understand human
movement to be such a great
artist.

He graphically illustrated
human movement.
The Profession of Podiatry
A French surgeon wrote the first book on the
treatment of foot conditions;
Menoire sur les cors des pieds.
Rousselot Paris 1755
From here on throughout Europe the
profession grew.
With many notable exponets – Durlacher (1792
1864), Zacharie (1827-1900), Runting (1861-1954),
Scholl (1882-1968)
The Profession of Podiatry


Podiatry is one of the few professions in and
around medicine that have independence of
diagnosis.
Podiatrists are expected to make their own
clinical decisions.
The Profession of Podiatry



The traditional skills of Chiropody maintained the
place of the practitioner as the expert in the
treatment of the skin and its excrescences.
The name change to Podiatry in the United States
(1957) and the introduction of Local Anaesthetic
brought about the expansion into foot surgery.
At the same time the world of biomechanics opened
up to the podiatrist and from this arguably the
podiatrist became the pre-eminent foot specialist.
Although recognition of this is still patchy world wide.
Merton Louis Root III. DPM, DSC, FACFO.
(13th August 1922 – 25th September 2002)

Root with his coauthors –Orien and
Weed - brought
podiatric
biomechanics into
the scientific
community.
Root’s contribution






Neutral position
Terminology
Classification of foot types
An understanding of open and closed chain
kinetics.
The concept of compensation
Tri-planar motion and its control
The Profession of Podiatry




Since the 70s the development of the profession has grown
rapidly.
UK podiatrists now have graduate level training with many
optional and mandatory post registration courses to follow.
The United Kingdom NHS now employs consultant grade
podiatrists in foot surgery and lower limb musculo-skeletal
medicine.
There are also many more at specialist grade working in
Diabetes, Rheumatology etc. (A sound, comprehensive knowledge
of the foot, it’s pathologies and pathomechanics is essential)
There are nearly 8000 Registered Podiatrists
working in the UK today.
The majority work in NHS clinics.
Approximately 1/3rd work in private practice
and some work in the commercial sector.
The NHS (England) 2002 total expenditure on
Chiropody/Podiatry £110 million.
Expenditure on private Chiropody/Podiatry
£70 million a year.
Scope of practice

Traditional skills

Complementary services

Specialist skills

Surgery
Traditional skills
Non invasive sharp
debridement.
Padding and strapping.
Drugs and dressings.
Insoles and shoe
adaptations.
Callused nodules from the affects of
Rheumatoid Arthritis.

Relieved with debridement
and padding
Neglect of the simplest foot lesion can
have catastrophic results
Complementary services

Physiotherapy type
techniques
–
eg laser

Acupuncture

Homeopathy/herbalism

Advanced Strapping
Specialist skills (Podiatric
Biomechanics)
Although the study of
human movement
related to foot function
underpins Podiatric
practice. The detailed
application of Podiatric
biomechanics can be
considered a speciality
Definition

Biomechanics is the science that examines forces
acting upon and within a biological structure and
effects produced by such forces.
Hay (1973)

Biomechanics is the science which studies
structures and functions of biological systems using
the knowledge and methods of mechanics.
Hatze (1971)
Podiatric biomechanics
Podiatric biomechanics is the study of forces
acting on the human body its structure and
function with particular reference to the lower
limb, the foot and related pathology.
(A combination of Kinesiology and kinematology)
The use of this information in various treatment
regimes to change these forces for more
efficient function.
The History of Biomechanics
The seven stages of biomechanical history (Nigg)
 Antiquity
650BC
 The middle ages
200AD
 The Italian renaissance
1450AD
 Scientific revolution
1600AD
 The age of enlightenment
1730AD
 The Gait century
1800AD
 The twentieth century and beyond
Antiquity continued

Plato (427-347BC)
–
He sowed the first
seeds of mechanics by
suggesting that the best
tool for the pursuit of
knowledge is
mathematics.
Aristole (384-322BC)
–
–
–
Wrote “About the Movement of
Animals” - the first scientific
analysis of gait.
To him observation was
paramount.
Aristole is also attributed as the
first to explain ground reaction
forces “…just as the pusher
pushes, so the pusher is
pushed” (Cavanagh 1990)
The Italian Renaissance

Leonardo DaVinci (1452-1519)



“The foot is the most marvellous of
machines – and a work of art”
A great thinker, mathematician,
inventor, military and civil engineer,
anatomist and dreamer. He needed
to understand human movement to
be such a great artist.
He graphically illustrated human
movement.
The Scientific Revolution

Sir Isaac Newton(1642-1727)

“If I have been able to see farther it was because I stood
on the shoulders of giants”


Galileo, Decatres, Kepler etc
His laws of motion provided the impetus to study human
movement and the tools to understand it.
Newton’s laws

1st law
–

A body will continue in a state of rest or uniform motion in
a straight line unless an external force acts upon it.
2nd law
–

(recap)
The rate of change of momentum of an object is directly
proportional to the force acting, and takes place in the
direction in which the force acts.
3rd law
–
To every action there is an equal and opposite reaction.
The Gait Century

Eduard (1795-1881) and Wilhelm Weber (1804-1891)
–

Die Mechanik der menschlichen Gehwerkzeuge’
(On the
mechanics of Human gait tools) established an agenda for research into
human gait.
Braune and Fischer




In 1891 1st tri-dimensional study of human gait.
Determined the Centre of Gravity of each body segment.
Etienne Jules Marey (1838-1904)
Edward Maybridge (1830-1904)
Etienne Jules Marey
Marey was a prolific
worker in the field of
biomechanics even
inventing and using a
pressure platform.
He also used
photography to help in
the understanding of
human movement.
Early motion analysis
by Etienne Jules Marey
Edward Maybridge


Maybridge was a pioneer of
photography particularly cine
and of human movement. He
linked with Marey.
The fore runners to twentieth
century biomechanics.
Twentieth century
Early workers
–
–
–
–
Jules Amar “The Human Motor” an analysis of physical and
physiological components of work.
Bernstein provided the bases of theories of motor control
amongst other things.
A.V.Hill initiated the understanding of muscle function.
Elftman estimated internal forces in muscles and joints –
developed a force platform.
The pioneering work of the California University
Biomechanics Lab. At San Francisco and Berkley.
Roots’ contribution
Like Newton “…..he saw far because he stood on the shoulders of
others.”







Triplanar motion and its control
Neutral position
Terminology
Classification of foot types
The concept of compensation
An understanding of open and closed chain kinetics.
And more
Root M, Orien W, Weed J; Normal and Abnormal foot function. (1977)
Planes as related to the foot

Frontal

Sagittal

Transverse
Neutral Position
Is this:–
–
–
–
–
–
–
A flat foot
A pronated foot
An everted heel
A valgus heel
Rear foot varus
Fore foot varus/valgus
Or just a woman with
knock knees
Compensations
Fore foot Valgus
Fore foot Varus
Open and Closed chain Kinetics.
Foot function
Why does the foot have 26 (or 25) bones
System of levers and pullies
The three
main
antipronation
muscles are:Tib. Anterior
Tib Posterior
Peroneus
Longus.
(Flexor
Hallucis)
Assessment???