DM - FOOT EVALUATION IN THE PRIMARY CARE SETTING “An ounce of prevention is worth a pound of cure.” – Benjamin Franklin Bernadette Pendergraph, Gloria Sanchez, MDs Cindy Mayeda, RN Department of Family Medicine, Harbor-UCLA

Learning Objectives Medical Knowledge a. Perform Comprehensive DM Foot Exam b. Implement ADA DM Foot Guidelines c. Classify DM Foot Ulcers Accurately d. List indications for imaging Patient Care a. Offloading Devices for DM Ulcers b. Utilize consultants in timely fashion No conflicts of interest

Learning Objectives System Based Practice a. Utilize resources for patients b. Expedite pt work up & tx PRN Interpersonal & Communication Skills a. Teach pts DM foot care & precautions b. Collaborate with HC team to examine & treat pts Professionalism a. Take “ownership” of DM foot ulcer

IMPORTANCE OF FOOT EXAMS National Hospital Discharge survey 1996 86,000 with DM under went > 1 amputation DM leading cause of amputation in lower extremities > 50% preventable Triad: neuropathy, deformity, trauma Absence of nerve and vascular complaints is not protective Incidence of: Foot ulcers up to 25% lifetime risk, annual risk 2% ~50% infected 14-24% amputation Lower extremity amputation 50% in same/opposite extremity in 5 yrs. Mortality all cause at 5 yr 39-68% http://www.emedicine.com/med/topic3547.htm Diabetic Foot Infections Last Updated: May 2, 2006 Burke A Cunha, MD, MACP, Professor of Medicine, State University of New York at Stony Brook School of Medicine; Chief, Infectious Disease Division, Winthrop-University Hospital

IMPORTANCE OF FOOT EXAMS Healthy People 2020 goals Increase # of persons receiving at least an annual foot exam Decrease amputations related to DM Ethnic risk for amputation per 10,000 persons with DM African-Americans 95.3 Hispanic 44.4 Caucasians 56 Annual foot exams (55-75%) Decrease amputations 11-5 per 1000

IMPORTANCE OF FOOT EXAMS % amputations related to DM Hispanics 82.7 African-Americans 61.6 Caucasians 56.8 Foot exam frequency By patient Daily 52% Never 22% By provider Type 1 66% Type 2 52%

COST OF DM FOOT DISEASE Amputations > $1.1 billion Ulcer in male 40-65 y.o. $28,000 over 2 yr

RISK FACTORS FOR AMPUTATION Arterial insufficiency: DM > 10 yrs, Tobacco use Disease control: high FBS, high A1c, duration = two fold increase Sex: male Eng Organ Damage: Retinopathy Nephropathy Cardiovascular disease Peripheral neuropathy: absent Achilles reflex, decreased vibratory sensation = 2 x likely in amputees Abnormal gait 15x more likely to injure Abnormal monofilament exam 60% develoed ulcers, 21% amputations over 32 months

RISK FACTORS FOR AMPUTATION Abnormal foot anatomy Nail – Onycholysis, Ingrown Skin – Xerosis, Corn, Callus, Hair loss Bone – Hallux valgus, hammer toes, prominent metatarsal heads, Charcot foot Previous ulcer or amputations Loss of monofilament perception – 18 fold increase risk of ulcer

PRECIPITATING EVENTS FOR AMPUTATION Injury from new shoes Improper toe nail trimming Accidental wounds Thermal injury 1/3 of injuries self induced in PVD

ADA GUIDELINES Everyone with DM gets a foot exam Prerequisite history Starts at diagnosis Frequency: At least annual – stratify high vs low risk Visual inspection every visit if neuropathy Prerequisite history Previous ulceration, amputation, Charcot joint, vascular surgery, angioplasty, tobacco use Symptoms of claudication or neuropathy DM complications: renal, visual Metabolic theory This theory proposes that hyperglycemia causes increased levels of intracellular glucose in nerves, leading to saturation of the normal glycolytic pathway. Extra glucose is shunted into the polyol pathway and converted to sorbitol and fructose by the enzymes aldose reductase and sorbitol dehydrogenase. Accumulation of sorbitol and fructose lead to reduced nerve myoinositol, decreased membrane Na+/K+-ATPase activity, impaired axonal transport, and structural breakdown of nerves, causing abnormal action potential propagation. This is the rationale for the use of aldose reductase inhibitors to improve nerve conduction. Vascular (ischemic-hypoxic) theory According to this theory, endoneurial ischemia develops because of increased endoneurial vascular resistance to hyperglycemic blood. Various metabolic factors, including formation of advanced glycosylation end products, also have been implicated. The end results are capillary damage, inhibition of axonal transport, reduced Na+/K+-ATPase activity, and finally axonal degeneration. Altered neurotrophic support theory Neurotrophic factors are important in the maintenance, development, and regeneration of responsive elements of the nervous systems. Nerve growth factor (NGF) is the best studied. This protein promotes survival of sympathetic and small-fiber neural crest–derived elements in the peripheral nervous system. In animals with diabetes, both production and transport of NGF are impaired. Antioxidants have been used to enhance the effects of NGF. Laminin theory Laminin is a large, heteromeric, curariform glycoprotein composed of a large alpha chain and two smaller beta chains, beta 1 and beta 2. In cultured neurons, laminin promotes neurite extension. Lack of normal expression of the laminin beta 2 gene may contribute to the pathogenesis of diabetic neuropathy. Autoimmune theory Autoimmune diabetic neuropathy is postulated to result from immunogenic alteration of endothelial capillary cells. This is the basis for the use of intravenous immunoglobulin (IVIg) to treat some variants of diabetic neuropathy.

ADA GUIDELINES FOR FOOT CARE Foot exam components Visual inspection: dermatologic, musculoskeletal, shoe Neurological assessment: 10g Monofilament + 1 of the following: Vibration Pinprick Ankle reflexes VPT Vascular: Pulses, consider ABI

DERMATOLOGIC INSPECTION Nails Shape/length Ingrown, paronychia Onycholysis Skin Xerosis Callus/Corn/Ulcer Temperature Pumice stone okay for DM without peripheral neuropathy

MUSCULOSKELETAL ASSESSMENT Deformities Toe deformities-claw , hammer Bunions Charcot foot

SHOE EVALUATION Look at the patient’s shoes (Are these shoes appropriate for these feet?) Type of material? Good: canvas, suede, leather, elastic Bad: plastic Any foreign objects? Depth appropriate? Width appropriate? Size? How old?

NEUROLOGIC ASSESSMENT Peripheral neuropathy most common cause of DM foot ulceration Identify loss of protective sensation (LOPS) 10 g monofilament 128 Hz turning fork: vibratory sensation-tip of great toe bilaterally Pinprick: disposable pin proximal to nail of great toe Ankle reflexes Vibration perception threshold testing: mean of 3 readings; VPT > 25V http://diabetes.niddk.nih.gov/dm/pubs/neuropathies/#types Analgesics: acetaminophen, NSAIDs, capsician, TCAs, anticonvulsants, TENS w/U: CBC/LYTES/LFTS/B12/THIAMINE/TSH/ESR/SPEP….CONSIDER ANA/RF/PARANEOPLASTIC ANTIBODIES STAGING: NO - No neuropathy N1a - Asymptomatic neuropathy detected as nerve conduction abnormality in at least 2 nerves N1b - N1a and abnormal neurologic examination N2a - Symptomatic mild diabetic polyneuropathy; sensory, motor, or autonomic symptoms; patient able to heel walk N2b - Severe symptomatic diabetic polyneuropathy (as in N2a, but patient unable to heel walk) N3 - Disabling diabetic polyneuropathy EmEDICINE Diabetic Neuropathy Last Updated: September 28, 2006

MONOFILAMENT TESTING Patient should close the eyes Check patient on proximal site to demonstrate Instruct the patient to tell you when he feels the monofilament Push the monofilament until it bends, then hold for 1-2 seconds Lift the monofilament from skin Retest the area where the patient did not feel the monofilament (Avoid callus) Mark the areas of the foot using a plus sign (+) if they can feel the monofilament and a minus sign (-) if they cannot Single use monofilaments or Booth and Young study

VASCULAR ASSESSMENT PAD is a component cause in 1/3 of ulcers Risk factor for recurrent wound Palpate dorsalis pedis and posterior tibialis If pulses are absent or symptoms of PAD, do ABI DM > 50 yo DM < 50 with multiple PAD risk factors

ABI Readings Abnormal >1.2 (medial calcinosis) Normal 0.9-1.2 Moderate Vascular Dz 0.4-0.8 Severe Vascular Dz <0.4

TOE PRESSURE TESTING (TBI) Consider doing if ABI > 1.2 Cut off are different than ABI TBI > 0.5 or > 70 mm Hg = normal TBI < 0.2 or < 30mm Hg = severely ischemic The cut-off values of toe pressure and TBI are arbitrary and vary in the literature. In general, a toe pressure of 70 to 110 mmHg or TBI > 0.5 to 0.75 is considered normal and anything below is diagnostic of PAD. A toe pressure lower than 30 mmHg or TBI < 0.2 is considered severely ischemic and diagnostic of critical limb ischemia (CLI). Wound healing potential drops as TBI decreases from the normal values

RISK CLASSIFICATION

FOOT CONDITIONS TO WATCH OUT FOR Diabetic foot infections: inframalleolar infection in a person with DM Acute: Predominantly g+ cocci Clindamycin Keflex Bactrim Augmentin Chronic: g-rods 2nd generation cephalosporin Linezolid Daptomycin Account for the greatest number of diabetes related hospital days

DIABETIC FOOT INFECTIONS Ischemia: obligate anaerobes Vascular evaluation Fluoroquinolone + clindamycin Imipenem Vancomycin + Ceftazidime + metronidazole

Afp 2008 G CSF: does not speed resolution of infection but decreases need for surgical intervention Hyerbaric oxygen: decreased risk of amputation

ULCERS Venous stasis ulcer Arterial insufficiency ulcer Medial malleolar area Irregular borders Red-brown staining Lower extremity edema/varicose veins Arterial insufficiency ulcer Tip of the toe Punched out (clear demarcation) Pale, dry base without edema Arterial Insufficiency and Ulceration: Diagnosis and Treatment Options ADVANCES IN SKIN & WOUND CARE,  Jun 2004  by Sieggreen, Mary Y,  Kline, Ronald A

WAGNER ULCER CLASSIFICATION Grade 0 = no ulcer in high risk foot Grade 1 = ulcer involving full skin thickness Grade 2 = ulcer to ligament and muscle Grade 3 = ulcer with cellulitis/abscess Grade 4 = localized gangrene Grade 5 = extensive gangrene involving whole foot

ULCER TREATMENT Patients should never walk out in the same shoe wear they walked in… Offload ulcer Modify shoe insert – cut out area under ulcer Healing boot Total contact cast Assess vascularity Wound care Inciting event – shoe, foreign body = xray Debridement Assess if Infected Close follow-up

FOOT CONDITIONS Charcot foot Neuropathic joint – progressive destruction of bone and soft tissues at weight bearing joints Rocker bottom foot with continued ambulation Incidence in DM: 0.15-2.5% Recurrence 5% Bilateral disease 10% Men = Women

PATHOGENESIS OF CHARCOT

STAGING

WHICH ONE IS CHARCOT FOOT?

NORMAL FOOT

CHARCOT FOOT Acute Chronic Inflammatory: swelling, increased temperature (3-7°F), redness, bony resorption Intact skin and pulses Insensate foot Treatment Immobilization: total contact cast Reduce stress: non-weight bearing r/o infection Chronic Protection: orthotics, surgery Neurotraumatic theory - This theory states that Charcot arthropathy is caused by an unperceived trauma or injury to an insensate foot. The sensory neuropathy renders the patient unaware of the osseous destruction that occurs with ambulation. This microtrauma leads to progressive destruction and damage to bone and joints. Neurovascular theory - This theory suggests that the underlying condition leads to the development of autonomic neuropathy, causing the extremity to receive an increased blood flow. This in turn results in a mismatch in bone destruction and synthesis, leading to osteopenia. anatomic system is described by Saunders and Mrdjencovich Pattern 1 involves the forefoot, which includes the interphalangeal joints, the phalanges, and the metatarsophalangeal joint. Pattern 2 involves the tarsometatarsal joint. Pattern 3 involves the cuneonavicular, talonavicular, and calcaneocuboid articulations. Pattern 4 involves the talocrural, or ankle, joint, which is the articulation of the tibia, the fibula, and the talus. Pattern 5 involves the posterior calcaneus. emedicine. Charcot Arthropathy Article Last Updated: Aug 29, 2007  Mrugeshkumar Shah, MD, MPH, Walter Panis, MD

TREATMENT OVERVIEW

OTHER ORTHOSIS Charcot foot AFO: offload bottom of foot and reduce ankle motion Total contact cast: transfer weight away from foot Pneumatic walker brace Fillers-foam or cork Special Report: Orthotic and Pedorthic Care Neuropathy, Charcot Joint Disease and Partial-Foot Amputations Volume 16 · Issue 3 · May/June 2006

OTHER ORTHOSIS Charcot foot Toe amputations AFO: offload bottom of foot and reduce ankle motion Total contact cast: transfer weight away from foot Toe amputations Toe filler Forefoot amputations: custom shoes Fillers-foam or cork Special Report: Orthotic and Pedorthic Care Neuropathy, Charcot Joint Disease and Partial-Foot Amputations Volume 16 · Issue 3 · May/June 2006

Achilles lengthening Transmetatarsal amputation

SHOE PRESCRIPTIONS Healing shoes: post op or heat molded shoes Depth in-lay: toe deformities, prescription inserts Extra wide: bunions Rocker sole: reduce pressure on metatarsal heads; hallux rigidis Custom molded: severe feet deformities www.1stepaheadfootcare.com/id5.html

SHOE PRESCRIPTIONS Medicare covers custom shoes for persons with DM, in a comprehensive DM care program and one of the following: H/o amputation H/o ulcer H/o preulcerative callus Peripheral neuropathy with callus Poor circulation Foot deformity Products for the year One pair of depth shoes with 3 inserts One pair of custom-molded shoes/inserts with 2 inserts

FOOT CARE INSTRUCTIONS Good sugar control Daily visual exam Moisturize your feet Appropriate shoe wear – never barefoot, no open toe box Firm heel counters and uppers – to prevent excessive motion and rolling A firm and wide outsole – to provide a stable base for the foot An extra-depth construction with a removable inlay – to provide added cushion; allow room for a custom foot orthosis www.amputee-coalition.org/inmotion/may_jun_06...

HOW TO DEAL WITH PROBLEMS Thermal injury Shoe color (8-13°) Bony abnormalities Mild deformities: Appropriate depth and width Athletic shoes Soft insoles: plastazote/urethrane viscoelastic Laces or Velco strap Severe deformities or amputation: Shoe prescription Relieve excessive pressure Decrease shock, sheer pressures Accommodate, stabilize, and support deformities

Medicare pays 80% of what is allowed Depth shoes $126 Custom molded shoes $378 Inserts $64

RISK FACTORS FOR FOOT ULCER Poor glycemic control Visual impairment Previous foot ulcer/amputation Peripheral neuropathy PAD Foot deformity DM nephropathy Cigarette smoking

High risk: amputation, ulcer Elevated A1c doubles risk of amputation