diabetic foot dr. sobia fin
TRANSCRIPT
Content
• Prevalence of Diabetic Foot• Pathophysiology • Classification • Diagnosis• Treatment• Diabetic Foot Education
Some Facts and Figures about Diabetic foot
• According to WHO, in 2010, there are more
than 8 million DM patients in Pakistan• Many patients are undiagnosed yet• Diabetes Mellitus is the largest cause of
neuropathy• Foot ulcerations is most common cause of
hospital admissions for Diabetics• Expensive to treat, may lead to amputation
and need for chronic institutionalized care
Prevalence of Diabetic Foot
• More than 80,000 amputations are performed on Diabetic patients each year in US
• 50% of people with amputations will develop ulcerations and infections in the contralateral limb within 18 months
• 58% will have a contralateral limb amputation 3-5 years after the first one
• 3 year mortality after first amputation is estimated as upto 50%
Some statistics of Diabetic Foot
• Foot problems account for 40% of healthcare resources in developing countries
Some statistics of Diabetic Foot
• 85% of all amputations begin with an ulcer
• 49-85% of amputations can be prevented if proper care is taken
Pathophysiology of Diabetic Foot
Diabetic Foot
PVD
InfectionsNeuropathy
PERIPHERAL VASCULAR DISEASES
Peripheral vascular disease in diabetes
15-40 times more likely to have lower limb amputation
People over 70 years have a 70-fold increased risk of amputation
An estimated 1 out of every 3 people with diabetes over the age of 50 have this condition *
Patients with PAD have an increased risk of MI and stroke*
* http://www.diabetes.org/living-with-diabetes/complications/peripheral-arterial-disease.html
Causes of Peripheral vascular disease
Diabetes Smoking Hypercholesterolemia Hypertension
Pathophysiology of PVD
Peripheral Vascular Disease is commonly caused by atherosclerosis and usually affects the tibial, peroneal, aorto-iliac or infra-inguinal arteries
Stages of PVD
1. Occlusive disease without symptoms
2. Intermittent claudication
3. Ischaemic rest pain (night time)
4. Ulceration/gangrene
Symptoms of PVD
Intermittent claudication which can occur in both but is often worse in one leg
Rest pain at night
Intermittent Claudication
Walking-induced pain in one or both legs that does not disappear with continued walking, and is relieved only by rest
Claudication is present in 15% to 40% of Pts with peripheral arterial disease and associated with a ↓ ability to perform daily tasks
Varying presentations of patients with PVD
PAD patients ≥50 yearsInitial presentation*
ClaudicationRest Pain10%–35% of patients
Atypical leg pain40%–50% of patients
Asymptomatic20%–50% of patients
* Excluding patients with an initial presentation of critical limb ischemia.Adapted from Hirsch AT et al. Available at: http://www.acc.org/clinical/guidelines/pad/summary.pdf. Accessed March 22, 2006.
The majority of PAD patients do not have the classical symptoms of claudicationThe majority of PAD patients do not have the classical symptoms of claudication
Signs of PVD
Dry flaky skin
Diminished or absent pedal pulses
Coolness of the feet and toes
Poor skin and nails
Absence of hair on feet and legs
Ulceration may occur in association
Initial Screening of PVD
History of Claudication
Assessment of Pedal Pulses
Obtain ABI Ankle Brachial Index
How to assess a patient with PVD• Palpation of foot
pulses
◦Dorsalis pedis (10% absent due to anatomical reasons)
◦Tibialis posterior
• Capillary filling time should also be checked
• CFT of >5 seconds is prolonged
How to diagnose PVD
1.ABI2. Duplex Imaging3. Diagnostic Angiogram
(less common now)4. Ultrasound5. MRI and CT
Hirsch AT et al. Available at: http://www.acc.org/clinical/guidelines/pad/summary.pdf. Accessed March 22, 2006.
Ankle-Brachial Pressure
The most cost effective tool for PVD
Measuring the cuff pressure by Doppler in the posterior tibial or anterior tibial arteries compared to the brachial artery
Intermittent claudication is associated with ABPI of 0.4-0.9
Values less than 0.4 is associated with critical limb ischemia
Duplex Imaging
Duplex arterial imaging – allows narrowing or obstruction of blood vessels to be localized
Diagnostic Angiogram
Performed through a percutaneous arterial catheter
Less commonly used now
PAD patients are at increased risk for CV ischemic events
PAD* (≥50 years old)5-year outcomes
Limb morbidity• 70%–80%
Stable claudication • 10%–20%
worsening claudication
• 1%–2% critical limb ischemia
CV morbidity
20%Nonfatal CV event (MI or stroke)
Mortality
15% to 30%▪ 75% from CV causes
* Patients with an initial clinical presentation of asymptomatic PAD, atypical leg pain, or claudication.Adapted from Hirsch AT et al. Available at: www.acc.org. Accessed March 22, 2006.
Up to 1/3 of PAD patients will die in 5 years, 75% from CV causesUp to 1/3 of PAD patients will die in 5 years, 75% from CV causes
Peripheral vascular disease
Treatment
• Quit smoking
• Walk through pain
• Surgical intervention
• Aim for an A1C below 7%
• Lower your blood pressure to less than
130/80 mmHg
• Get your LDL cholesterol below 100 mg/dl
Distinguishing features of
Ischemia
Symptoms Claudication
Rest pain
PalpationCold, pulseless
InspectionDependent ruborTrophic changes
UlcerationPainful Heels and toes
Diabetic Neuropathy
Neuropathy
Changes in the vasonervorum with resulting ischemia
Increased sorbitol in feeding vessels block flow and causes nerve ischemia
Intraneural accumulation of advanced products of glycosylation
Abnormalities of all three neurologic systems contribute to ulceration
Types of Diabetic Neuropathy
There are four types of diabetic neuropathy:
Peripheral Sensory neuropathy (also called diabetic nerve pain and distal polyneuropathy)
Proximal neuropathy (also called diabetic amyotrophy)
Autonomic neuropathyFocal neuropathy (also called
mononeuropathy)
Peripheral neuropathy – sensory motor
Most common form of neuropathyAffects approximately 50% after 15
yearsAffects long nerves (feet and legs)
first◦glove and stocking distribution
BilateralEqual symptoms in both limbs
Sensory Neuropathy
• Loss of protective sensation• Starts distally and migrates proximally in
“stocking” distribution• Large fibre loss – light touch and
proprioception• Small fibre loss – pain and temperature• Usually a combination of the two
Sensory nerve damage
Nerve damage – neuropathy
Symptoms:PainNumbness (loss of feeling)TinglingMuscle weaknessMuscle cramping and/or
twitchingInsensitivity to pain and/or
temperatureExtreme sensitivity to even
the lightest touchSymptoms get worse at night
Autonomic Neuropathy
• Regulates sweating and perfusion to the limb
• Loss of autonomic control inhibits thermoregulatory function and sweating
• Result is dry, scaly and stiff skin that is prone to cracking and allows a portal of entry for bacteria
Autonomic nerve damage
Motor Neuropathy
• Mostly affects forefoot ulceration– Intrinsic muscle wasting – claw toes– Equinus contracture
Motor nerve damage
Acute painful Neuropathy
A common complication of Diabetes
The two types of neuropathies associated with pain are acute sensory nueropathy and chronic sensorimotor neuropathy
Hyperglycemia remains the major causative factor but PDN can also be seen in patients having HBA1C < 8%
Smoking Hyperlipidemia Hypertension Obesity
Causes of PDN
Treatment of PDN
Glycemic Control Correction of metabolic
derangements Medications e.g Tricyclic
Antidepressants like Duloxetine Antiepileptics like Gabapentins
and Pregablin and Carbamazepine
Tramadol
Painless nature of diabetic foot disease
Localized callus
Diabetic peripheral neuropathyscreening tests
Test sensation ◦Biothesiometer◦Tuning fork◦10 gm monofilament
Ankle reflexes
Assessment of high risk characteristics
Motor Neuropathy and Foot Deformities
Hammer toes
Claw toes
Prominent metatarsal heads
Hallux valgus
Collapsed plantar arch
Hammer Toes
Claw Toes
© 2002 American Diabetes AssociationFrom The Uncomplicated Guide to Diabetes ComplicationsReprinted with permission from The American Diabetes Association
© 2002 American Diabetes AssociationFrom The Uncomplicated Guide to Diabetes ComplicationsReprinted with permission from The American Diabetes Association
Hallux Valgus
Boulton, et al. Guidelines for Diagnosis of Outpatient Management of Diabetic Peripheral Neuropathy. Diabetic Medicine 1998, 15:508-512
Sensory Neuropathy in Diabetes
Loss of protective sensation in feetDetect with 5.07/10-g Semmes-Weinstein
monofilament◦50% of insensate patients have no
symptoms
Diabetes Care. 2006;29(Suppl 1):S24Diabetes Care. 2004;27:1591
Monofilament Testing
Test characteristics:◦Negative predictive value = 90%-98%◦Positive predictive value = 18%-36%
Prospective observational study:◦80% of ulcers and 100% of amputations
occur in insensate feet◦Superior predictive value vs. other test
modalities
J Fam Pract. 2000;49:S30 Diabetes Care. 1992;15:1386
Using the Monofilament
Demonstrate on forearm or handPlace monofilament perpendicular
to test siteBow into C-shape for 1 secondTest 4 sites/foot Heel testing does not
predict ulcer Avoid calluses, scars,
and ulcers
Monofilament Testing Tips
Insensate at 1 site = insensate feet
Falsely insensate with edema, cold feet
Test annually when sensation normal
Use monofilament ◦< 100 times day ◦Replace if bent◦Replace every 3 months
Vibration Testing
Biothesiometer◦Best predictor of foot ulcer risk
128-Hz tuning fork at halluces◦Equivalent to 10-g monofilament◦Newly recommended by ADA
Diabetes Care. 2006;29(Suppl 1):S25
Diabetes Res Clin Pract. 2005;70:8
Management of NeuropathiesSensory Neuropathy• A shoe neither too tight nor too
roomy is appropriate
Autonomic Neuropathy together with senosry
• An insole should provide optimal distribution of pressure, reduction of sheer stress and shock absorption
Charcot’s Arthropathy
Charcot foot is a sudden softening of the bones in the foot that can occur in people who have significant nerve damage (neuropathy). The bones are weakened enough to fracture, and
with continued walking the foot eventually changes shape.
As the disorder progresses, the arch collapses
and the foot takes on a convex shape, giving it a rocker-bottom appearance, making it very difficult to walk.
Charcot’s Arthropathy
Charcot foot is a very serious condition that can lead to severe deformity, disability, and even amputation
Charcot’s arthropathy
Charcot’s Arthropathy
Charcot foot symptoms may include:
Warmth to the touch (the footfeels warmer than the other) Redness in the foot Swelling in the area Pain or soreness
Management of Charcot’s Foot
Treatment for Charcot foot consists of:Immobilization. Because the foot and
ankle are so fragile during the early stage of Charcot, they must be protected so the soft bones can repair themselves.
Complete non-weightbearing is necessary to keep the foot from further collapsing. The patient will not be able to walk on the affected foot until the surgeon
Management of Charcot’s Foot
During this period, the patient may be fitted with a cast, removable boot, or brace, and may be required to use crutches or a wheelchair. It may take the bones several months to heal, although it can take considerably longer in some patients.
Custom shoes and bracing. Shoes with special inserts may be
needed after the bones have healed Surgery. In some cases, surgery may be
required.
DIABETIC FOOT INFECTIONS
Some facts about Diabetic foot Ulcer
Diabetic foot problems such as ulceration, infections and gangrene are the most common cause of hospitalization among Diabetic patients
Evaluating the Patient with a DFI
Patient◦Systemic response Fever, chills, sweats, cardiovascular status
◦Metabolic status Hyperglycaemia, electrolyte imbalance, hyperosmolality, renal impairment
◦Cognitive function Delirium, depression, dementia, psychosis
◦Social situation Support, self-neglect
· Limb/Foot Wound
Evaluating the Patient with a DFI
Limb or Foot ◦Vascular (Ischaemia , Venous
insufficiency)◦Neuropathy◦Infection
Wound ◦Size, depth ◦Necrosis, gangrene◦Infection
DIABETIC FOOT ULCERS
Diabetic Foot Ulcer
The enormity of the global burden of diabetic foot disease…this much neglected, but potentially devastating, complication of a disease that is reaching epidemic proportions…Someone, somewhere, loses a leg because of diabetes every 30 seconds of everyday…”
Lancet. 2005;366:1674
Prevalence of Diabetic foot ulcer
25 % of diabetics will develop a foot
ulcer
40-80% of these ulcers will become infected
25 % of these will become deep
10-30 % of patients with a diabetic foot ulcer will go on to amputation
Etiology of Diabetic Foot Ulcer
The majority of foot ulcers appear to result from minor trauma in the presence of sensory neuropathy
The critical triad is most commonly seen in patients with diabetic foot ulcers are peripheral sensory neuropathy, deformity and trauma
Hyperglycemia remains the mainstay in the onset and progression of neuropathy
Causal Pathways for Foot Ulcers
Neuropathy
Deformity
ULCER
% Causal Pathways
Neuropathy: 78%
Minor trauma: 79%
Deformity: 63%
Behavioral ?
Diabetes Care. 1999; 22:157
Poor self-foot care
Minor Trauma- Mechanical (shoes)- Thermal- Chemical
Pre-ulcer Cutaneous Pathology
Persistent erythema after shoe removal
Callus with subcutaneous hemorrhage
FissureInterdigital maceration, fungal
infectionNail pathology
AJM Boulton, H Connor, PR Cavanagh, The Foot in Diabetes, 2002
Pre-ulcer
A patient comes with the complain of pre-ulcer (callus with subcutanoeus hemorrhage on the tip of the third digitThis pre-ulcer (callus with subcutaneous hemorrhage) on the tip of the third digit with its claw-toe deformity could easily go undetected. Pre-ulcers must be promptly and carefully debrided to determine if there is already an underlying ulcer.
Case Study
Treatment
In this patient debridement did not reveal an underlying ulcer.
Debridement of callus reduces subcutaneous pressure and helps to prevent subcutaneous hemorrhage and progression to an ulcer. This patient’s socks and shoe gear will have to be modified to accommodate his claw-toe deformities.
Case Study (Cont..d)
Case Study
64-year-old obese man
Type 2 DM (15 yrs)◦ BP (18 yrs)◦ Dyslipidemia (18 yrs)◦ CABG (10 yrs ago)◦ Claudication (today; 25 yds)
Insulin/Metformin/Statin/ACEI/HCTZ/ASAComes with the complain “Sore on my
left foot, Doc”
Case Study (continued)
Clinical evaluation of heel ulcer:◦Probe reached bone◦Extensive subcutaneous abscess
MRI: extensive osteomyelitis
ABI: 0.2
Angiography: Inoperable severe vascular disease
Uncontrolled infection
Amputation necessary
Tragic “Rule of 50”
50% ofamputations
50% of patients
50% of patients
Transfemoral/transtibial level
2nd amputation in 5 years
Die in 5 years
Clinical Care of the Diabetic Foot, 2005
Tragic “Rule of 15”
15% of diabetes Foot ulcer in lifetimepatients
15% of foot ulcers Osteomyelitis
15% of foot ulcers Amputation
Clinical Care of the Diabetic Foot, 2005
Evaluation of Diabetic Foot Ulcer
Documentation of the wound’s size, shape, location, depth, base and border.
A sterile stainless steel probe is used to assess the depth of wound up till the bone, tendon or joint
X-rays should be done MRI is also useful for detecting
osteomyelitis, and deep abscess
Team Care
Identification of high-risk patients Detection of early problemsEducate/motivate self-care
behaviorsProphylactic nail/skin careTherapeutic footwearPrompt, multidisciplinary treatment
of ulcers
Lancet. 2005;366:1676
Team Care Reduces Ulcers/Amputations
50%-80% reductions in ulcers/amputations possible with Team Care
Economic modeling studies◦Cost-effective if 25%-40% reduction in
ulcer rate◦Cost-saving if > 40% reduction in ulcer
rateLancet. 2005;366:1719
Diabetes Care. 2004;27:901
Treatment of Diabetic Foot Ulcers
Debridement:
Removal of all necrotic tissue, peri wound callus, and foreign bodies down to viable tissue
After debridement, wound is irrigated with saline or cleanser and a dressing is applied
Dressings available are hydrogels, foams, calcium alginates and skin replacement
Treatment of Diabetic Foot Ulcers
Debridement:
In case of abscess, incision and drainage are essential with debridement
Treating a deep abscess with antibiotics alone leads to delayed therapy and further mortality and morbidity
Treatment of Diabetic Foot Ulcers
Offloading Proper offloading remains the biggest
challenge for HCPs Having patients use a wheelchair or
crutch is the most effective method of offloading
Total contact Casts (TCC) are difficult but significantly reduce pressure on wounds
Post operative shoes or wedge shoes are also used but proper fitting is necessary
Treatment of Diabetic Foot Ulcers
Infection Control Coverage of gram positive and gram
negative organisms like methicillin resistant Staph. Aureus, B-hemolytic Strep. Pseudomonas and enterococci
Patients should be hospitalised and and treated with IV antibiotics
Mild to moderate infection can be treated as OPD with Cephalexin, Amoxicillin with Clavulanate Potassium, Moxifloxacin or Clindamycin
Detecting Feet-at-risk
History:◦Prior amputation or foot ulcer◦Peripheral artery disease (PAD)
Exam:◦Insensate ◦Foot deformities◦Absent pulses◦Prolonged venous filling time◦Reduced ABI◦Pre-ulcerative cutaneous pathology
Arch Intern Med. 1998;158:157
Prevalence of Amputation
50 % of patients with cellulitis will have another episode within 2 years
25-50 % of diabetic foot infections lead to minor amputations
10-40 % require major amputations
Cause of diabetic amputation
Trauma
Ulcer
Failure to heal
Infection
Amputation
Neuropathy or vascular disease
Physical Examination of the Feet in Persons with Diabetes
Risk categorization system
Category Risk profile Check-up frequency
0 No sensory neuropathy Once a year
1 Sensory neuropathy Every 6 months
2 Sensory neuropathy /peripheral vascular disease/ foot deformities
Every 3 months
3 Previous ulcer Every 1-3 months
Outcomes By IDSA DFI Severity Classification
Armstrong, Lavery, Peters, Lipsky. Clin Infect Dis 2007
3% 3%
46%
78%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
No infection Mild Moderate Severe
LE AmputationX2 trend = 108, p < 0.0001
None Mild Moderate Severe
6%10%
54%
89%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
No infection Mild Moderate Severe
HospitalizationX2 trend = 118.6, <0.0001
None Mild Moderate Severe
1666 patients enrolled in prospective diabetic foot study
Diabetic Foot Education
Most foot problems are preventable
Upto 85% of foot problems are preventable through early identification and prompt treatment by skilled health professionals.
Diabetic Voice, March 2005, Volume 50, Issue 1
Targeting education according to level of risk
Wide spectrum of foot risk; people require different levels of education
Should be considered when providing footcare education
Lifestyle changes only required for those at high risk
Evidence-based stratification of services
Ulcer
High
Low
High-risk foot clinic
Intensive foot education and podiatry
Neuropathy, previous amputation or ulcer
Peripheral vascular diseaseUnable to feel monofilamentNeuropathy, no previous amputation or ulcer
General information
No neuropathy
Which people should we target for footcare education?
Footcare education
Low risk◦simple advice◦no lifestyle change◦annual foot assessment
High risk◦intensive education◦practical demonstrations◦significant behavioural changes
◦focus on prevention
Footcare education
Which behaviour- and lifestyle-changing strategies do we teach people with diabetes when they are at high risk?
Wash, touch and look at feet every day
Do not soak feetTest water temperatureWash and dry between
toesAvoid herbs and
ointmentsExamine feet in good
light
Learn to look for:
Bruises
Cuts
Blisters
Learn to look for:
Cracked heels Callus
Learn to look for:
Hammer toe Clawed toes
Learn to look for:
Bunion Charcot’s arthropathy
Learn to look for:
Foot infection
Learning to care for skin
Moisturiser – preferably in a pump bottle
Massage with cream – not in open sores or between toes
Without perfume
How to care for toenails
Do not to let nail grow too long
Cut straight across
File sharp edges
Ask a friend or relative
How to treat tinea
Anti-fungal lotion between toes
Anti-fungal cream on feet
Treat affected area and surrounding skin
What to do about fungal nails
Difficult to treatThick nails should be
filed
What to look for in socks
Wool or cottonPadded socksNo tight topsNo rough seamsKnee-high stockings not
advisable
What to look for in a shoe
Wide and deep at the toe
Thick rubber soleNo high heelsFirm heel counterLace-up or velcro Smooth lining
Footwear
When buying shoes
Buy in the afternoon
Measure both feet
Stand up to fit
Wear in slowly
Never wear new shoes all day
Being extra careful
Before putting on shoes, check for
rough spots or loose objects
Preventing burns
Use sunblock on exposed skin
At least 3 m from heater
Turn off electric blankets
No hot water bottles
Never walk barefoot
Exercise
Walk only as far as is absolutely necessary
Non-walking exercises
Basic Footwear Education
DontsPointed
toesSlip-onsOpen
toesHigh
heelsPlasticBlack
colorToo small
Dos
Broad-round toesAdjustable (laces,
buckles, Velcro)Athletic shoes,
walking shoesLeather, canvasWhite/light colors½” between longest
toe and end of shoeDiabetes Self-Management. 2005;22:33
Identify problem and act quickly
If no sign of improvement,
contact doctor or emergency
servicesRemember,
people with neuropathy
do not feel pain!
Footcare educational material
Written material complements education
Written at average reading age
Large font for visually impaired
Pictures should be relevant to text
Evaluating the foot education program
Evaluate behavioural change – not knowledge
‘How many times have you checked your feet this week?’ ‘How many times have you put cream on your feet this week?’
Key messages
Stratify people according to level of risk
Educate those at high riskShoes are the most common
cause of ulcerationIdentify problems early and treat
promptlyHealth professionals need to be
trained in diabetic foot care
Key messages
Get regular check-ups from a foot and ankle surgeon
Check both feet every day—and see a surgeon immediately if there are signs of Charcot foot
Be careful to avoid injury, such as bumping the foot or overdoing an exercise program
An amputation occurs every 30 seconds due to diabetes