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The Clinical application
of Podiatric
Biomechanics
David N
Dunning
DipPodM. MChS.
MSc.
PGCert.(sports
pod)
www.dunningandtrinder.co.uk
Aims of podiatric management
Every facet of upright activity is a biomechanical event.
As we have seen the foot is designed to take stress.
The objective of any treatment intervention is to:
Reduce the stress on the structures to an acceptable
level.
Return the limb to as close to normal as possible
Pronation

Pronation is good
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Excessive pronation is bad
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Lack of resupination is very bad
Pronation
Pronation – Abduction, Eversion and
Dorsi-flexion
Supination – Adduction, Inversion and
Plantar-flexion
What are the main shock absorbers?
Management options
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1st Aid (R.I.C.E.)
Drugs
Physical therapies
Orthoses
Footwear
Exercise
Advice
Surgery
Rest Ice Compression Elevation
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Rest – if possible. In some conditions some
pain is acceptable to the committed athlete.
Ice – in the acute stages.
Compression – not always easy to do.
Elevation – following activity. (Whilst icing)
Drugs
The use of steroid injections
is very useful in some
cases but for instance in
Achillodynia they are to be
avoided as they have been
associated with
spontaneous rupture.
NSAIDs can be useful. But
there is evidence that there
long term use can delay
the healing process.
(Elongates the Regeneration phase)
Physical therapies
Frictions and mobilisations, but not
in the acute phase
Ultra sound etc. – this can enhance
the inflammatory process thus
reducing the “lag time” to the
next two phases.
Stretching and strengthening.
Orthoses
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There are many
different types.
Not just medial wedges.
Tri-planar (casted)
devices.
Preformed (non-casted)
orthoses
Must be used in all
shoes?

More later
Footwear
Shock absorption – good or
bad?
Rear-foot control.
Heel tabs.
Must be stable – Muscle
conflict.
Exercise
Stretching involves:1)
2)
Keeping the Tri-ceps
Surae group functional
through it’s full range.
Therapeutically reorganising the fibres of
both muscles to help in
rehabilitation.
Eccentric exercises.

Eccentric muscle action – contraction whilst lengthening.

Plyometrics – hopping, bounding or depth jumps ???
(Are these types of exercise really appropriate for
structures that may be in a weakened state???)
Advice
Change activity where
possible.
Look closely at all
footwear.
Fit for purpose
Foot orthoses
The functional foot orthosis is an orthosis, which is
designed to promote structural integrity by resisting
all stance phase forces, that would cause abnormal
skeletal motion or position, while allowing normal
motion during the stance phase of gait.
William P. (Bill) Orien (2001)
The orthosis must:

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Support any forefoot deformity that would exert an
abnormal retrograde force on the rear foot:
Resist abnormal extrinsic or intrinsic forces that
would cause excessive medial or lateral distribution
of weight into the rear foot, causing abnormal sub
talar joint and mid tarsal joint pronation or supination
during the time of gait that the heel is bearing weight;

Promote normal rear foot pronation during
the contact period of gait for shock
absorption and assist in re-supination of the
foot as it moves toward propulsion. Resist
forces that promote abnormal pronation of
the rear foot during the stance phase of gait.
A non-functional foot orthosis
The noun orthosis is derived from the Greek Orthomeaning to correct or straighten.
The standard arch support of old can not be referred to
as a foot orthosis unless it straightens or corrects an
abnormality. Generally the material is too soft to
resist ground reaction forces, or if it is of a hard
material, because of its’ position, it would be too
uncomfortable to wear.
FHL – Either the foot hurts or the back hurts!!
Pre-formed or non-casted devices.
These are foot orthoses that have a functional
element yet are not made from a positive
cast.
Bearing in mind Dr. Oriens’ definition then if an
“off the shelf” device can achieve these aims
it can be referred to as “functional”
A functional device should:
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Support for forefoot anomalies.
Resist forces acting on the calcaneus.
Provide shock absorption.
Provide for normal function.
Fit well.
Be manufactured with the appropriate
materials.
Preformed devices.
Vectorthotic is just one
example
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Soft EVA cover.
Hot glue stick on
forefoot posting
Marked for 1st ray cut
out.
Hard but heat
mouldable shell.
Clip on rear foot posts.
Foot orthoses

Control the mechanics
of the foot and lower
limb
Slipper casts
Foot orthoses and shoe
adaptation go “hand in glove”
Excuse the expression
To recap:
Treatment options.
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Advice
Physio, drugs etc.
Strapping – short term
Serial casting
Temporary orthoses
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Balanced (casted) orthoses
Footwear
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Preformed, work shop manufactured
Surgery
Adaptations, Modular or bespoke
Case histories
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FHL
Bunnions
Achillodynia
Heel spur syndrome
Metatarsalgia
Diabetes
RhA