DIABETIC FOOT

dr. Ngr Gd Boyke A.W.

Epidemiology

40% - 60% of all non traumatic lower limb amputation

85% of diabetic related foot amputation are preceded by foot ulcer

4 out of 5 ulcer in diabetics are precipitated by trauma

4% -10% is the prevalence of foot ulcer in diabetics

Patophysiology

Systemic burden due to high blood sugars

• damaging white cells to reduce leucocyte function.

• disrupting blood vessel endothelium giving diabetic microangiopathy thereby reducing tissue perfusion

• giving microorganisms an ideal environment to proliferate and infect ulcers

Diabetic foot ulcers may have multiple causes

A. Peripheral neuropathy (nerve damage)

B. Peripheral vascular disease (poor pedal blood supply)

C. Traumai. Acute: any injury to the foot such as burns or cuts

ii. Chronic: due to foot deformities (changes of foot shape that lead to ill-fitting shoes and, thereby, ulceration)

Pathophysiology

Neuropathy

Motor Sensory Autonomic

↓ nociception

↓ Proprioception,Unawarenessof foot position Reduced

sweating

Dry skin

Fissures andcracks

Muscle wastingFoot weakness

Postural deviation

Deformities, stressand shear pressures

*Shunts: blood vessels that bypass capillaries and lead directly from arteries to veins

Trauma

Stress on bones & jointsPlantar pressure

Callus formation

InfectionUlcer

Neuropathy

Peripheral arterial disease

Artherosclerosis narrows or blocks the arterial lumen

Foot ischaemia

Foot ulcer Necrosis/ Gangrene

Infection

Artheroma plaque narrowing the arterial lumen

Ischaemic toes due to artherosclerosis

Peripheral Arterial Disease

Assestment

The aim of the assessment is to examine each pathological cause that creates ulcers:

1) peripheral neuropathy 2) peripheral arterial disease3) structural

Structural Abnormalities

Peripheral Arterial Assessment

Skin changesEvidence of infectionCallous or ulcerRange of motionCharcot foot

TemperatureSkin changesAnkle Brachial Index

Neuropathy Assessment 10 gram monofilament

Tuning Fork (vibration)

How to Perform Proper Foot Examination

History• burning, tingling, numbness of the footExamination• Test for reduced power and reflexes that are

evidence of muscular motor deficits. • Test sensation by skin pinprick (spinothalamic

tracts), proprioception and vibration (dorsal columns)

Assessment Peripheral Neuropathy

• Place a 10g nylon Semmes-Weinstein monofilament to the skin

• Apply pressure until the monofilament buckles

• Inability to perceive the 10g of force applied by the monofilament is associated with clinically significant large fibre neuropathy and an increased risk of ulceration (sensitivity of 66 to 91%)

• Test 4 plantar sites on the forefoot (great toe and the base of 1st, 3rd and 5th metatarsals ) to identify 90% of patients with an insensate foot.

Monofilament test

Assessment Monofilament for pressure sensation (pinprick sense)

• Apply a vibrating 128 Hz tuning fork to the bony prominence of the big toe

• If the patient cannot feel the vibration, gradually move the fork upwards

Tuning fork test

Assessment Tuning Fork (vibration)

• History : claudication (calf pain after walking a specific distance) that is relieved by rest. However this is uncommon in people with diabetes due the concomitant neuropathy.

• Examination: Palpate the foot for temperature (cool in PVD); palpate the dorsalis pedis pulse and, if absent, the posterior tibial pulse.

Palpation of the dorsalis pedis pulse Palpation of the posterior tibial pulse

Assessment Peripheral Vascular Disease (PVD)

Measure the blood pressure (BP) in the arm using a sphygmanometer

Measure the blood pressure in the foot. Place a BP cuff around the calf and detect the dorsalis pedis pulse using a small hand-held doppler. Inflate the cuff and slowly deflate until the pulse appears.

The ankle brachial pressure index (ABPI) is the ratio of the ankle systolic pressure to brachial systolic pressure.

ABPI is usually >1 but in the presence of peripheral vascular disease is <1.

Doppler being used to detect the dorsalis pedis pulse

Assessment Investigations: ankle brachial pressure index

Structural abnormalities and deformities lead to bony prominences which are associated with high mechanical pressure on the overlying skin.

Common abnormalities / deformities include:i. Callusii. Claw toesiii. Charcot footiv. Nail deformities

Callus on plantar surface

Assessment Structural Abnormalities and Deformities

Claw toesCharcot foot

deformity

Nail deformity

The presence of infection needs to be defined clinically rather than microbiologically.

An infected ulcer

Signs suggesting infection include; 1. purulent secretions2. presence of friable tissue (slugh)3. foul odour

Infected Ulcers

Simple investigations include:• Tissue specimens or material obtained from the bottom

of a wound for gram staining and culture for microbial sensitivity.

• Full blood count, urea and electrolytes, inflammatory markers (ESR and CRP) for assessing severity of infection

• Plain X-ray of the leg for signs of bone damage, presence of foreign body, or gas in soft tissue (gas gangrene)

Assessment Infected Ulcers: Investigations

KLASIFIKASI ULSER KAKI DIABETIK WAGNERDerajat (GRADE) Lesi

GRADE O

GRADE 1

GRADE 2

GRADE 3

GRADE 4

GRADE 5

TIDAK TERDAPAT LESI TERBUKA, MUNGKIN HANYA DEFORMITAS DAN SELULITIS

ULSER SUPERFISIALIS

ULSER DALAM SAMPAI TENDON, ATAU TULANG

ULSER DALAM DENGAN ABSES, OSTEOMILITIS DAN INFEKSI PERSENDIAN

GANGREN LOKAL-KAKI DEPAN (FORE FOOT)

GANGREN PADA SELURUH KAKI

Management

Treatment of diabetic foot ulcers largely depends on the underlying causes:

ischaemia, neuropathy or a combination of both.

Local factors

Systemic factors

Wound care

Pressure offloading

Debridement (nonischemic wounds)

Revascularisation

Glycemic control

Treat infection

Address lower-extremity vascular status

Multidisciplinary Team Approach

Ischaemic necrosis of a toe and an extensive

plantar ulcer

Medical: reduce cardiovascular risk factors

Surgical: revascularisation•Angioplasty•Open bypass surgery

Management Ulcers due to Ischaemia

• Padding• crutches, wheelchairs

The common site for a neuropathic ulcer

The key to treatment here is to redistribute plantar pressure.

Management Ulcers due to Neuropathy

In both isacheamic and neuropathic ulcers, treatment is based on debridement of the wound and dressing application.

Debridement is the removal of necrotic and dead tissue in order to enhance healing.

Debridement is undertaken to:

• Remove callus in neuropathic foot to lower plantar pressure

• Assess the true dimension of the ulcer

• Drain exudate and remove dead tissue

• Take a deep swab for culture

• Encourage healing and restore a chronic wound to an acute wound

Forcep and a scalpel is the usual technique by cutting

away of all slough and non-viable tissue.

Management Wound Debridement

Amputation is made on clinical findings that the ulceration is not healing/ infection worsening in spite of intensive antibiotic therapySigns include:Extensive tissue lossUnreconstructable ischaemiaFailed revascularisationCharcot’s of ankle with instability

Management Amputation

•Empirically based upon clinical experience and local preferences•Antibiotics are modified on the basis of clinical response and and wound culture / sensitivity results.•For mild infections, 7-10 day course is usually sufficient. Severe infections may need up to 2-3 weeks of treatment.

Management Infected Ulcers - Antibiotics

Summary

• Diabetic foot ulcers may have multiple causes• The aim of the assessment is to examine each

pathological cause that creates ulcers • Multi-disciplinary approach needed• Treatment of diabetic foot ulcers largely

depends on the underlying causes