Foot complications are among the
most serious and costly
complications of diabetes mellitus.
Amputation of all or part of a lower
extremity is usually preceded by a
foot ulcer. A strategy which
includes prevention, patient and
staff education, multi-disciplinary
treatment of foot ulcers, and close
monitoring can reduce amputation
rates by 49-85%. Therefore, several
countries and organizations, such as
the World Health Organization and
the International Diabetes
Federation, have set goals to reduce
the rate of amputations by up to
50%.
The basic principles of prevention
and treatment described in these
guidelines are based on the
International Consensus on the
Diabetic Foot. Depending on local
circumstances, these principles have
to be translated for local use,
taking into account regional
differences in socio-economics,
accessibility to healthcare and
cultural factors. These Practical
guidelines are aimed at healthcare
workers involved in the care of
people with diabetes. For more
details and information on treatment
by specialists in foot care, the
reader is referred to the
International Consensus document.
Pathophysiology
Although the spectrum of foot
lesions varies in different regions
of the world, the pathways to
ulceration are probably identical in
most patients. Diabetic foot lesions
frequently result from two or more
risk factors occurring together. In
the majority of patients, diabetic
peripheral neuropathy plays a
central role: up to 50% of people
with diabetes with type 2 diabetes
have neuropathy and at-risk feet.
Neuropathy leads to an insensitive
and sometimes deformed foot, often
with an abnormal walking pattern. In
people with neuropathy, minor trauma
- caused for example by ill-fitting
shoes, walking barefoot or an acute
injury - can precipitate a chronic
ulcer. Loss of sensation, foot
deformities, and limited joint
mobility can result in abnormal
biomechanical loading of the foot.
Thickened skin (callus) forms as a
result. This leads to a further
increase of the abnormal loading
and, often, subcutaneous
haemorrhage.
Whatever the primary cause, the
patient continues walking on the
insensitive foot, impairing
subsequent healing (see Figure 1).
Peripheral vascular disease, usually
in conjunction with minor trauma,
may result in a painful, purely
ischaemic foot ulcer. However, in
patients with both neuropathy and
ischaemia (neuro-ischaemic ulcer),
symptoms may be absent, despite
severe peripheral ischaemia.
Micro-angiopathy should not be
accepted as a primary cause of an
ulcer.
Illustration of ulcer due to
repetitive stress
1. Callus formation
2. Subcutaneous hemorrhage
3. Breakdown of skin
4. Deep foot infection with
osteomyelitis
Cornerstones
of foot management
There are five key elements which
underpin foot management:
Regular inspection and
examination of the foot at
risk
Identification of the foot
at risk
Education of patient, family
and healthcare providers
Appropriate footwear
Treatment of non-ulcerative
pathology
1 Regular
inspection and examination
All people with diabetes should be
examined at least once a year for
potential foot problems. Patients
with demonstrated risk factor(s)
should be examined more often -
every 1-6 months. The absence of
symptoms does not mean that the feet
are healthy; the patient might have
neuropathy, peripheral vascular
disease or even an ulcer without any
complaints. The patient's feet
should be examined with the patient
lying down and standing up, and
their shoes and socks should also be
inspected.
History and
examination
History
Previous
ulcer/amputation, previous
foot education, social
isolation, poor access to
healthcare, bare-foot
walking
Neuropathy
Symptoms, such as
tingling or pain in the
lower limb, especially at
night
Vascular status
Claudication, rest pain,
pedal pulses
Skin
Colour, temperature,
oedema
Bone/joint
Deformities (e.g. claw
toes, hammer toes) or bony
prominences
Footwear/socks
Assessment of both
inside and outside
Sensory loss
Sensory loss
due to diabetic
polyneuropathy can be
assessed using the following
techniques:
Pressure perception
Semmes-Weinstein
monofilaments (10 g, see
addendum) The risk of future
ulceration can be determined
with a 10 g monofilament
Vibration perception
128 Hz tuning fork
(hallux, see addendum)
Discrimination
Pin prick (dorsum of
foot, without penetrating
the skin)
Tactile sensation
Cotton wool (dorsum of
foot)
Reflexes
Achilles tendon reflexes
2
Identification of the at-risk foot
Following examination of the foot,
each patient can be assigned to a
risk category, which should guide
subsequent management.
Progression of
risk categories:
Sensory neuropathy and/or
foot deformities or bony
prominences and/or signs of
peripheral ischemia and/or
previous ulcer or amputation
Sensory neuropathy
Non-sensory neuropathy
Areas at risk
3 Education
for patients, family and healthcare
providers
Education, presented in a structured
and organized manner, plays an
important role in the prevention of
foot problems. The aim is to enhance
motivation and skills. People with
diabetes should learn how to
recognize potential foot problems
and be aware of the steps they need
to take in response. The educator
must demonstrate the skills, such as
how to cut nails appropriately.
Education should be provided in
several sessions over time, and
preferably using a mixture of
methods. It is essential to evaluate
whether the person with diabetes has
understood the messages, is
motivated to act, and has sufficient
self-care skills. An example of
instructions for the high-risk
patient and family is given below.
Furthermore, physicians and other
healthcare professionals should
receive periodic education to
improve care for high-risk
individuals.
How
to cut nails
Items which
should be covered when instructing
the high-risk patient
Daily feet
inspection, including
areas between the toes
The need for another
person with skills to
inspect feet, should the
people with diabetes be
unable to do so (If
vision is impaired,
people with diabetes
should not attempt their
own foot care.)
Regular washing of
feet with careful
drying, especially
between the toes
Water temperature -
always below 37º C
Do not use a heater
or a hot-water bottle to
warm your feet.
Avoidance of
barefoot walking indoors
or outdoors and of
wearing of shoes without
socks
Chemical agents or
plasters to remove corns
and calluses - should
not be used
Daily inspection and
palpation of the inside
of the shoes
Do not wear tight
shoes or shoes with
rough edges and uneven
seams.
Use of lubricating
oils or creams for dry
skin - but not between
the toes
Daily change of
socks
Wearing of stocking
with seams inside out or
preferably without any
seams
Never wear tight or
knee-high socks.
Cutting nails
straight across (see
Figure 3)
Corns and calluses -
should be cut by a
healthcare provider
Patient awareness of
the need to ensure that
feet are examined
regularly by a
healthcare provider
Notifying the
healthcare provider at
once if a blister, cut,
scratch or sore has
developed
Inappropriate footwear is a major
cause of ulceration. Appropriate
footwear should be used both indoors
and outdoors, and should be adapted
to the altered biomechanics and
deformities - essential for
prevention. Patients without loss of
protective sensation can select
off-the-shelf footwear by
themselves. In patients with
neuropathy and/or ischaemia, extra
care must be taken when fitting
footwear - particularly when foot
deformities are also present. The
shoe should not be too tight or too
loose (see Figure 4). The inside of
the shoe should be 1-2 cm longer
than the foot itself. The internal
width should be equal to the width
of the foot at the site of the
metatarsal phalangeal joints, and
the height should allow enough room
for the toes. The fit must be
evaluated with the patient in
standing position, preferably at the
end of the day. If the fit is too
tight due to deformities or if there
are signs of abnormal loading of the
foot (e.g. hyperaemia, callus,
ulceration), patients should be
referred for special footwear
(advice and/or construction),
including insoles and orthoses.
Internal width of the shoe
5 Treatment of
non-ulcerative pathology
In a high-risk patient, callus, and
nail and skin pathology should be
treated regularly, preferably by a
trained foot care specialist. If
possible, foot deformities should be
treated non-surgically (e.g. with an
orthosis).
Foot ulcers
A standardized and consistent
strategy for evaluating wounds is
essential, and will guide further
therapy. The following items must be
addressed:
Cause
Ill-fitting shoes are the most
frequent cause of ulceration, even
in patients with 'pure' ischaemic
ulcers. Therefore, shoes should be
examined meticulously in all
patients.
Type
Most ulcers can be classified as
neuropathic, ischaemic or
neuro-ischaemic. This will guide
further therapy. Assessment of the
vascular tree is essential in the
management of a foot ulcer.
If one or more pedal pulses are
absent, or if an ulcer does not
improve despite optimal treatment,
more extensive vascular evaluation
should be performed. As a first
step, the ankle brachial pressure
can be measured. An ankle brachial
pressure index (ABPI) below 0.9 is a
sign of peripheral arterial disease.
However, ankle pressure might be
falsely elevated due to
calcification of the arteries.
Preferably, other tests, such as
measurements of toe pressure or
transcutaneous pressure of oxygen
(TcPo2) should be used. Figure 5
gives an estimate of the chance of
healing using the tests. If a major
amputation is being contemplated,
the option of revascularization
should be considered first.
Graphs:
Non-invasive evaluation and
estimate of probability of healing
Figure 1: A schematic
estimate of the probability of
healing of foot ulcers and minor
amputations in relation to ankle
blood pressure, toe blood pressure
and transcutaneous oxygen pressure
(TcPo2) based on selected reports
Site and depth
Neuropathic ulcers frequently occur
on the plantar surface of the foot,
or in areas overlying a bony
deformity. Ischaemic and
neuro-ischaemic ulcers are more
common on the tips of the toes or
the lateral border of the foot.
The depth of an ulcer can be
difficult to determine, due to the
presence of overlying callus or
necrosis. Therefore, neuropathic
ulcers with callus and necrosis
should be debrided as soon as
possible. This debridement should
not be performed in ischaemic or
neuro-ischaemic ulcers without signs
of infection. In neuropathic ulcers,
debridement can usually be performed
without (general) anaesthesia.
Signs of
infection
Click here for the Specific
guidelines on diagnosing and
treating the infected diabetic foot
Infection in a diabetic foot
presents a direct threat to the
affected limb, and should be treated
promptly and actively. Signs and/or
symptoms of infection, such as
fever, pain or increased white blood
count/ESR, are often absent.
However, if present, substantial
tissue damage or even development of
an abscess is likely.
The risk of osteomyelitis should be
determined. After initial
debridement, if it is possible to
touch bone with a sterile probe, it
is likely that the underlying bone
is infected.
A superficial infection is usually
caused by Gram-positive bacteria. In
cases of (possible) deep infections,
Gram stains and cultures from the
deepest tissue involved are advised
- not superficial swabs. These
infections are usually
polymicrobial, involving anaerobes
and Gram-positive/negative bacteria.
Ulcer
treatment
If treatment is based on the
principles outlined below, healing
can be achieved in the majority of
patients. Optimum wound care cannot
compensate for continuing trauma to
the wound bed, or for ischaemia or
infection. Patients with an ulcer
deeper than the subcutaneous tissues
should be treated intensively, and,
depending on local resources and
infrastructure, hospitalization must
be considered.
Mechanical
off-loading - the
cornerstone in
ulcers with
increased
biomechanical stress
Total contact
casting or other
casting techniques -
preferable in the
management of
plantar ulcers
Temporary
footwear
Individually
moulded insoles and
fitted shoes
Non-weight
bearing
limitation
of standing and
walking
crutches,
etc.
Restoration of skin
perfusion
Arterial
revascularization
procedures: results
do not differ from
people without
diabetes, but distal
revascularization
procedures
(angioplasty or
bypass-surgery) are
needed more
frequently.
The benefits of
pharmacological
treatment to improve
perfusion have not
been established.
Emphasis should
be placed on
cardiovascular risk
reduction (cessation
of smoking,
treatment of
hypertension and
dyslipidaemia, use
of aspirin).
Control of
exudate and
maintenance of moist
environment
Consideration of
negative pressure
therapy in
post-operative
wounds
The following
treatments are not
established in
routine management:
Biological
active products
(collagen, growth
factors,
bio-engineered
tissue) in
neuropathic ulcers
Systemic
hyperbaric oxygen
treatment
Silver or other
anti-microbial
agents containing
dressings
Note: footbaths are
contra-indicated as
they induce
maceration of the
skin.
Education for patient
and relatives
Instruction
should be given on
appropriate
self-care and how to
recognize and report
signs and symptoms
of (worsening)
infection - fever,
changes in local
wound conditions or
hyperglycaemia.
Determining the cause
and preventing
recurrence
The cause of the
ulceration should be
determined in order
to reduce the chance
of recurrences.
Ulcers on
contra-lateral foot
should be prevented
and heel protection
provided during
periods of bed rest.
Once the episode is
over, the patient
should be included
in a comprehensive
foot-care programme
with life-long
observation.
Organization
Effective organization requires
systems and guidelines for
education, screening, risk
reduction, treatment, and auditing.
Local variations in resources and
staffing will often determine the
ways in which care is provided.
Ideally, a foot care programme
should provide the following:
Education for patients,
carers and healthcare staff in
hospitals, primary healthcare,
and the community
A system to detect all
people who are at risk, with
annual foot examination of all
known patients
Measures to reduce risk,
such as podiatry and appropriate
footwear
Prompt and effective
treatment
Auditing of all aspects of
the service to ensure that local
practice meets accepted
standards of care
An overall structure which
is designed to meet the needs of
patients requiring chronic care
- rather than simply responding
to acute problems when they
occur.
In all
countries, at least three levels of
foot-care management are needed:
Level 1
General practitioner,
podiatrist, and diabetic
nurse
Specialized foot centre
with multiple disciplines
specialized in diabetic foot
care
Setting up a multidisciplinary foot
care team has been found to be
accompanied by a drop in the number
of amputations. If it is not
possible to create a full team from
the outset, this should be built up
step by step, introducing the
various different disciplines at
different stages. This team must
work in both primary and secondary
care settings.
Ideally, a foot-care team would
consist of a diabetologist, surgeon,
podiatrist, orthotist, educator, and
plaster technician, in close
collaboration with an orthopaedic,
podiatric and/or vascular surgeon
and dermatologist.
Addendum
Sensory foot
examination
Neuropathy can be detected using the
10 g (5.07 Semmes-Weinstein)
monofilament, tuning fork (128 Hz),
and/or cotton wisp.
Semmes-Weinstein monofilament
Sensory examination should
be carried out in a quiet and
relaxed setting. First apply the
monofilament on the patient's
hands (or elbow or forehead) so
that he or she knows what to
expect.
The patient must not be able
to see whether or where the
examiner applies the filament.
The three sites to be tested on
both feet are indicated in
Figure 6.
Apply the monofilament
perpendicular to the skin
surface (Figure 7a).
Apply sufficient force to
cause the filament to bend or
buckle (Figure 7b).
The total duration of the
approach - skin contact and
removal of the filament - should
be approximately 2 seconds.
Apply the filament along the
perimeter of, not on, an ulcer
site, callus, scar or necrotic
tissue.
Do not allow the filament to
slide across the skin or make
repetitive contact at the test
site.
Press the filament to the
skin and ask the patient whether
they feel the pressure applied
('yes'/'no') and next where they
feel the pressure ('left
foot'/'right foot').
Repeat this application
twice at the same site, but
alternate this with at least one
'mock' application in which no
filament is applied (total three
questions per site).
Protective sensation is
present at each site if the
patient correctly answers two
out of three applications.
Protective sensation is absent
with two out of three incorrect
answers - the patient is then
considered to be at risk of
ulceration.
Encourage the patients
during testing by giving
positive feedback.
The healthcare provider
should be aware of the possible
loss of buckling force of the
monofilament if used for too
long a period of time.
Sites to be tested with
monofilaments
Application of the monofilaments
Tuning fork
The sensory exam should be
carried out in a quiet and
relaxed setting. First, apply
the tuning fork on the patient's
wrists (or elbow or clavicle) so
that he or she knows what to
expect.
The patient must not be able
to see whether or where the
examiner applies the tuning
fork. The tuning fork is applied
on a bony part on the dorsal
side of the distal phalanx of
the first toe.
The tuning fork should be
applied perpendicularly with
constant pressure (Figure 8).
Repeat this application
twice, but alternate this with
at least one 'mock' application
in which the tuning fork is not
vibrating.
The test is positive if the
patient correctly answers at
least two out of three
applications, and negative ('at
risk for ulceration') with two
out of three incorrect answers.
If the patient is unable to
sense the vibrations on the big
toe, the test is repeated more
proximally (malleolus, tibial
tuberositas).
Encourage the patient during
testing by giving positive
feedback.
How to use a tuning fork
Easy to use foot screening
assessment sheet for clinical
examination
The foot is at risk if any
of the below are present
