Neuropathic Ulcers (lecture 6)

why is insulin needed

to transport glucose into cells to be used for aerobic / oxidative metabolism to create ATP within the mitochondria.

what is type 1A diabetes

juvenile diabetes or IDDM, auto-immune mediated, there is some genetic predisposition

what is type 1B diabetes

idiopathic, appears strongly hereditary

what happens in type 1 diabetes

in the langerhans cells of the pancreas an effector T cell recognizes peptides from the B cell specific proteins and kills the B cell. No insulin is made but glucagon and somatostatin are still produced.

what happens when there is glucose starvation

other substrates such as fat and protein produce ATP which is insufficient and not life compatible.

what is the pathogenesis of DM type II

obesity and hereditary factors which leads to insulin resistance which leads to eventual failure of pancreatic insulin secretion/glucose regulation and ongoing insulin resistance

what are advanced glycosylated end products

glycosylated proteins that mediate intimal free radical damage / inflammation

what are macro-vascular effects of poor glycemic control

atherosclerotic mediated CAD, PAD, cerebrovascular disease

what are microvascular and intracellular effects of poor glycemic control

peripheral neuropathy, retinopathy, nephropathy and other opathies

what is severity and prevalence of complications of diabetes directly related to

time and degree of glycemic control

what is a good range for hemoglobin / A1C for wound healing

below and 8/7% or less than 150 mg/dL glucose

what is there increased risk for with a greater than 8% hemoglobin/A1C

5x risk of amputation since the wound cannot heal

what is the primary cause of neuropathic ulcers

neuropathy due to motor, sensory, and autonomic neuropathy

motor neuropathy leads to

weakness / altered biomechanics of gait and intrinsic foot muscle weakness and deformity which increases areas of excessive pressure especially with inadequate footwear

sensory neuropathy leads to

a decrease / prevention of detection of these areas of abnormal and excessive pressure

autonomic neuropathy leads to

trophic skin changes (dry, abnormal regulation) with abnormal skin responses to excessive pressure (callus and impaired repair) which can result in pre-ulcerative callus and central ulceration

how many people with DM have had an ulcer on the foot or ankle

15%

what is the primary causative factor in LE amputations

diabetes

what is the survival rate for those with an amputation

50%

are neuropathic ulcers painful

there is no or very little pain due to a lack of sensation

where do neuropathic ulcers commonly occur

hallux, metatarsal heads, lateral midfoot, toes

what is the presentation of neuropathic ulcers

round / oval with callus rim, desiccated, necrotic base is uncommon unless there is infection or ischemia

what does the periwound of neuropathic ulcers look like

dry, cracked, callus. sometime edema or hyperkeratotic nails if pre-ulcerative callus

what is the exudate of neuropathic ulcers

low/moderate drainage that can very greatly and have mild odor

is there a pulse present with neuropathic ulcers

they are diminished or absent

what is the temperature of neuropathic ulcers

decreased if impaired blood flow or warm with edema with autonomic dysfunction

ulcer grade 0

pre-ulcerative lesion or healed ulcer

ulcer grade 1

superficial ulcer without subQ tissue involvement

ulcer grade 2

penetration through the subQ tissue, may expose bone, tendon, ligament, etc.

ulcer grade 3

abscess, osteomyelitis, joint sepsis

ulcer grade 4

gangrene of digit that is localized

ulcer grade 5

gangrene of entire foot

what is charcot foot deformity

lax ligaments and weak muscles which leads to a rockerfoot with midfoot collpase.

what foot deformities should you observe with neuropathic ulcers

charcot foot deformity, gastroc-soleus mm length, strength, gait

what monofilament helps to detect a loss of protective sensation

5.07 which is 10 grams of force

what monofilament helps to detect absent sensation

6.10 which is 75 grams of force

how do you check vascular integrity

pulses and capillary refill

what percentage of ulcers is due to improper foot wear

55%

what are important patient education things for people with neuropathic ulcers

glucose management, offloading, foot protection and appropriate foot wear, daily foot inspections

what are the signs and symptoms of hypoglycemia

nervous, shakey, tachycardia, impaired vision, impaired cognition

what is the gold standard for offloading

total contact casting since it has even pressure distribution and people cannot take it off so they adhere to protocols. You can use it with charcot deformity. It protects the foot from infection and helps to control edema.

disadvantages of total contact casting

cannot assess foot on a daily basis, affects sleeping and bathing, exacerbates postural instability or causes balance issues, cannot use with infection or impaired vascular status

wound care for neuropathic ulcers

add moisture adding dressings since they are typically dry, saucerization of callus rim to promote epithelialization, be aware of osteomyelitis risk

what are PT interventions

ROM and joint mobs to correct altered biomechanics, gait training with assistive device to off load, balance for fall prevention, aerobic exercise to increase functional capacity

offloading decision making

ability to remove / redistribute all pressures from the ulcer site, cost-effectiveness / insurance coverage, likelihood of patient adherence, saftey with balance and gait

what is the CPG recommendation for a diabetic foot ulcer

to prescribe a progressive moderate to vigorous intensity exercise program including aerobic and resistance training. Individualize to the patient.

how long should people maintain offloading with newly closed DFU's

moderate to maximal offloading for the first 3 months then gradually start weight bearing with a wear schedule

important notes for footwear with diabetic foot ulcers

always wear shoes even inside the home, proper fit and socks, check inside of shoes, limit activities that cause foot trauma

each 1% increase in HbA1c is associated with

a 2 fold increase in amputation risk