L6: Diabetic Foot Flashcards
Def of Diabetic Foot
- Infection, ulceration or destruction of deep tissues associated with neurological abnormalities & various degrees of peripheral vascular diseases in the
lower limb (based on WHO definition)
Epidemeology of Diabetic Foot
Pathophysiology of Diabetic Foot
Pathogenesis of Neuropathy
- Changes in the vasa nervosa
- Metabolic disorders with release of nerve toxic substance ( e.g. end glycation product)
what types of nerves does neuropathy affect?
- Motor Nerves
- Autonomic nerves
- Sensory nerves (most important)
Motor nerves affection in neuropathy (Diabetic Foot)
wasting of small muscles of the foot ——> foot deformities —–> abnormal pressure area
Autonomic nerves affection in neuropathy (Diabetic Foot)
- Dryness of the skin and loss of sweat and oil secretion which leads to excessive callus formation and skin cracks.
- Loss of neurogenic component of inflammatory response blunted inflammatory response and less severe signs of a severe infections.
Sensory nerves affection in neuropathy (Diabetic Foot)
- Sensory loss of superficial and deep sensation is the
most important part of sensory affection - Patients are unaware of trauma to the foot (loss of
protective mechanism) pressure sores over weight bearing points of the foo
Pathogenesis of Ischemia in DM
- Accelerating atherosclerosis in diabetic patients
- Usually atherosclerosis affects small size arteries (anterior tibial, posterior tibial and dorsalis pedis)
Pathophysiology of infection in DM
Peripheral Neuropathy
- Sensory and autonomic neuropathy provides site of
entry of organisms and blunt neurogenic immune
response.
Metabolic
- Hyperglycemia a state of immuno-suppression
Diabetic foot microbiology
- Usually in limb threatening diabetic foot infections there is polymicrobial bacterial infection with gram positive, gram negative, and anaerobic bacterial
infection .
Clinical Picture of Diabetic Foot
- Trophic ulcers (either ischemic or neuropathic)
- Dystrophic changes
- Gangrene & previously amputated toes or foot
Compare between Ischemic & Neuropathic Ulcers in terms of:
- Site
- Temperature
- Sensation
- Pulse
- Pain
- Deformity
Examination of Diabetic Foot
- Dermatological
- Neurological
- Vascular
Dermatological assessment of Diabetic Foot
Neurological assessment of Diabetic Foot
Vascular assessment in Diabetic Foot
Dorsalis pedis and posterior tibial artery examination
Investigations in Diabetic Foot
- DM
- CBC
- Culture & Sensitivity
Imaging studies in Diabetic Foot
- Plain X ray
- MRI scan
- Bone scan and radio-active labeled leukocyte scan
- Pedobarography
Plain X ray in Diabetic Foot
it is the basic study in all patients with diabetic foot it can show:
- osteomyelitis, bone fractures, joint dislocations
- foreign bodies
- gas due to gas forming infections
- soft tissue inflammatory hypertrophy
MRI in Diabetic Foot
- very sensitive in detecting the extent of soft tissue infection and bone and joint involvement
Bone scan and radio-active labeled
leukocyte scan Diabetic Foot
are of low clinical importance
Pedobarography in Diabetic Foot
Computerized method to detect points of high pressure in patients with neuropathic ulcers
Vascular scan in Diabetic Foot
- Duplex Scan
- Angiography
- MRA
Duplex scan in Diabetic Foot
- can be done to evaluate blood vessels in non-limb threatening infections and in follow up
Angiography in Diabetic Foot
- It is done when planning for vascular reconstruction in case of ischemic diabetic infections
MRA in Diabetic Foot
- Is used in case of severe renal impairment and severe dye hypersensitivity which is not uncommon in diabetics
Diabetic Foot Ulcer Control
Metabolic Control for Foot Ulcer
- In all stages tight Glycemic control is important.
- Insulin therapy based
- Control of BP, Dyslipidemia & Cessations of Smoking is required.
Mechanical Control for Foot Ulcer
- Off-loading —-> neuroischemic ulcers healing
Educational Control for Foot Ulcer
- Routine foot care for all diabetics.
- Prophylactic diabetes foot ware & trauma Prevention education to high risk patient.
- Education regarding early sign of infection & immediate reporting.
- Rehabilitation & Psycho-social support in patient with major Amputation
Vascular Control for Foot Ulcer
- In severe ischemic foot attempts to improve vascular perfusion by angioplasty or bypass surgery
TTT of Diabetic Foot
- TTT pf neuropathic ulcer
- TTT of infection
TTT of Neuropathic ulcers
TTT of infections in diabetic foot
what is the corner stone in treatment of diabetic foot infection?
Surgical drainage
Foot Care in Diabetic Foot
Joints can be affected by neuropathy resulting in the so called Charcot foot —–> It is painless progressive degenerative arthropathy
..
Causes of Neuropathic Arthropathy (Charcot Joint)
loss of proprioceptive and pain sensation —–> loss of foot architecture & deformity —-> abnormal press diabetic foot
CP of Neuropathic Arthropathy (Charcot Joint)
- Swelling and deformity
- Signs of inflammation.
- Profound unilateral swelling
- Increase in localized temp
- Erythema
- Joint effusion
- Unequal dorsalis pedis artery
MAnagement of Neuropathic Arthropathy (Charcot Joint)
Radiology:
- X-ray & MRI
Therapy:
- Diabetic control
- Bisphosphonate therapy
- Off loading
- Surgery
