[09.13] PE of Diabetic Feet V2

Constellation of physical findings and medical complications in the foot arising as a consequence of diabetes

What is the definition of diabetic foot?

Impaired sensation due to neuropathy, impaired blood supply, impaired wound healing, and impaired mobility

What four primary consequences lead to the development of diabetic foot?

Diabetes Mellitus

What is the leading cause of nontraumatic lower extremity amputation?

Loss of protective sensation

Which pathophysiologic factor allows a patient to sustain major or repeated minor trauma to the foot without knowing?

Disordered proprioception

What interferes with the normal protective mechanism and causes abnormal weight bearing while walking?

Calluses and ulceration

What two things form as a result of abnormal weight bearing while walking?

Motor and sensory neuropathy

Which two types of neuropathy lead to abnormal foot muscle mechanics and structural changes?

Hammer toe, claw toe, prominent metatarsal heads, and Charcot joint

Name four structural changes in the foot caused by neuropathy.

Anhidrosis and altered superficial blood flow

What are the two primary results of autonomic neuropathy in the foot?

Drying of the skin and fissure formation

What two skin conditions are promoted by anhidrosis?

Peripheral Artery Disease and poor wound healing

Which two factors impede the resolution of minor skin breaks?

Infection

What is the ultimate consequence of skin breaks that enlarge due to poor healing?

Inspection, assessment of vascular supply, and assessment of neurologic function

What are the three major components of the physical examination of diabetic feet?

Both legs to above the knees

How much of the patient's body should be exposed for the foot inspection?

Nails well trimmed and skin moisture

What two aspects of general foot hygiene are assessed during inspection?

Fissure formation and ulcers

What does dry skin make the patient prone to?

Petroleum jelly or lotion

What two products should a physician advise a patient to apply for dry skin?

Atrophy of the skin and muscles, hair loss, and thickened nails

Name four inspection findings caused by chronic ischemia.

Calluses, ulcerations, prior amputations, and joint deformities

Name four specific things to look for during the inspection phase.

Risk factor for subsequent ulcer formation and amputation

What is the clinical significance of a prior amputation noted during inspection?

Rounder or oblique

What are the two recommended shapes for the toe box of shoes?

Pointed

What shoe shape predisposes toes to friction and ulcer formation?

Corns

What are small, tender areas of thickened skin that look like corn kernels?

Joints on the top or side of the toe

Where are corns usually located?

Callus

What is a rough, thickened area of skin caused by repeated irritation or pressure?

Larger and thicker

How do calluses compare in size and thickness to corns?

Kalyo

What is the Filipino term for callus?

Soles of the feet

Where are calluses usually located?

Hammer toe

Which joint deformity results from a muscle imbalance putting pressure on toe tendons and joints?

Tighten and cannot stretch out

What happens to the muscles in the joints if the toe is bent in one position long enough?

Shoes that narrow toward the toe

What type of footwear pushes smaller toes into a flexed or bent position?

High heels

What specific shoe feature forces the foot down and increases pressure on a bent toe?

Bunion

What joint deformity involves an enlargement on the side of the foot near the base of the big toe?

Hallux

What is the medical term for the big toe?

Toward the second toe

In which direction does the big toe lean in a bunion deformity?

Deformity worsens and becomes painful

What happens to a bunion deformity over time if left untreated?

Tinea pedis

Which fungal infection causes itching, redness, and cracking?

Scratching and fissures

By what mechanism does tinea pedis lead to serious ulcer formation?

Onychomycosis

Which condition involves nails that are discolored, thick, brittle, and may separate from the nail bed?

Dark, moist, and warm

What three environmental factors in shoes promote fungal growth?

Charcot arthropathy

What is the technical name for Charcot foot?

Joint dislocations, pathologic fractures, and debilitating deformities

Name the three characteristics of Charcot arthropathy.

Diabetes

What is a major cause of Charcot foot involving bone and soft tissue destruction?

Weight bearing joints

At what specific anatomical sites does Charcot foot result in bone destruction?

Loss of natural arch

What causes the rocker bottom appearance in Charcot foot?

Lack of sensation and pain

Why do patients continue to walk on a deformed Charcot foot?

Microfractures and bone fractures

What occurs inside the foot as a patient continues to walk on a Charcot deformity?

Foot ulcer

What is defined as a break in the skin or a deep sore that can become infected?

Callus, fissure, or crack

An ulcer usually starts as one of which three findings?

Poor wound healing

What factor causes a crack or fissure to progress into an infection?

University of Texas Classification

Which classification system uses numbers 0 to 3 for depth and letters A to D for infection/ischemia?

0 to 3

What is the numerical range used for wound depth in the University of Texas system?

A, B, C, D

What letters are used for infection and ischemia in the University of Texas system?

Pre or post ulcerative lesion that is completely epithelialized

Describe Grade 0 in the University of Texas system.

Superficial wound

Describe Grade 1 in the University of Texas system.

Wound penetrating tendon or capsule

Describe Grade 2 in the University of Texas system?

Wound penetrating bone or joint

Describe Grade 3 in the University of Texas system?

Completely epithelialized

What does letter A represent in the University of Texas classification?

With infection

What does letter B represent in the University of Texas classification?

With ischemia

What does letter C represent in the University of Texas classification?

With infection and ischemia

What does letter D represent in the University of Texas classification?

IsChemia

What is the mnemonic for the letter C in the University of Texas system?

Both

What is the mnemonic for the letter D in the University of Texas system?

Wound penetrates tendon and capsule with infection and ischemia

What does a classification of 2D mean in the University of Texas system?

Loss of hair and gangrene

Name two physical clues for ischemia in the foot.

Arterial doppler ultrasound

What confirmatory test is used to check for ischemia?

Pus, foul smell, erythema, and warmth

Name four physical clues indicating an infection in a foot ulcer.

Wagner Classification

Which simpler system uses grades 0 to 5 for diabetic foot ulcers?

No ulcer in a high risk foot

What does Wagner Grade 0 represent?

Superficial ulcer involving full skin thickness but no underlying tissues

What does Wagner Grade 1 represent?

Deep ulcer penetrating to ligaments and muscle but no bone involvement

What does Wagner Grade 2 represent?

Deep ulcer with cellulitis or abscess and often osteomyelitis

What does Wagner Grade 3 represent?

Localized gangrene

What does Wagner Grade 4 represent?

Extensive gangrene involving the whole foot

What does Wagner Grade 5 represent?

Temperature and distal pulses

What two components are assessed during the vascular supply check?

Lateral to the extensor tendon of the great toe

Where is the dorsalis pedis artery located?

Posterior and inferior to the medial malleolus

Where is the posterior tibial artery located?

Popliteal artery

Which artery should be assessed if both the dorsalis pedis and posterior tibial pulses are weak?

Occlusion is above the knee

What is suggested if the popliteal artery is weak?

Occlusion is more distal

What is suggested if the popliteal artery is normal but distal pulses are weak?

Ankle Brachial Index

What is a simple inexpensive diagnostic test for peripheral artery disease?

0.9 to 1.3

What is the normal resting ABI range?

PAD

What diagnosis is suggested by an ABI of less than 0.9?

Doppler ultrasound

What tool is used to obtain systolic pressures for the ABI?

Dorsalis pedis and posterior tibial

Which two ankle arteries are used to obtain the systolic pressure for ABI?

Whichever is higher between the two

Which pressure value is selected from the ankle pulses for the computation?

Whichever is higher between the two

Which pressure value is selected from the arm pulses for the computation?

Highest ankle systolic / higher arm systolic

How is the ABI computed for a specific leg?

83 to 99 percent

What is the specificity level of the ABI for detecting more than 50 percent stenosis?

50 to 79 percent

What is the sensitivity range of the ABI?

Non compressible

How is an ABI reading of greater than 1.3 interpreted?

Mild to moderate peripheral arterial disease

How is an ABI reading between 0.41 and 0.9 interpreted?

Severe peripheral arterial disease

How is an ABI reading between 0.00 and 0.4 interpreted?

Hand held Doppler, ultrasound gel, and manual blood pressure cuff

Name the three materials needed for an ABI.

Lying supine, comfortable, and relaxed

What should the patient's state be for an ABI measurement?

10 minutes

How long should the patient rest to stabilize blood pressure before an ABI?

Allowed to speak

What is a patient not allowed to do during the ABI test?

Brachial Systolic Pressure

What does BSP stand for?

Eliminate the signal

What is the purpose of inflating the blood pressure cuff during the Doppler assessment?

Pressure at which the signal returns

At what point is the pressure reading taken while deflating the cuff for BSP or ASP?