Diabetic foot

1. DIABETIC FOOT
Anirudhya.J (Unit 2)

2. • Diabetic foot is defined as the foot of diabetic patients
with ulceration, infection and/or destruction of deep
tissues associated with neurological abnormalities and
various degrees of peripheral vascular disease in lower
limb.

3. • DM is the leading cause of non traumatic lower extremity
amputation.
• Foot ulcers and infections are also a major source of morbidity
in these individuals.
• The reason for the increased incidence of these disorders in DM
involve the interaction of several pathogenic factors :
-Neuropathy
-Abnormal foot biomechanics
-Peripheral arterial disease
-Poor wound healing

4. Diabetes mellitus
Neuropathy PVD
Motor Sensory Autonomic
Intrinsic
muscle
wasting
Decreased
pain and
propriocept
ion
Anhydrosis
Ischemic foot
Trauma
Foot
deformity
Motor
dysfunction
Dry skin
Fissure
Callus
AV
shunting
Charcot
joint
disease
Foot ulceration
High plantar foot pressures
Clinical pathways leading to foot ulceration

5. Risk factors for foot ulcers or amputation
• Male sex
• Diabetes > 10 years / Poor glycemic control
• Peripheral neuropathy
• Peripheral arterial disease (PAD)
• Abnormal structure of foot (Callus, bony
abnormalities, Thickened nails)
• Smoking
• Visual impairment
• History of previous ulcer or amputation

6. Wagner’s Grading of ulcers:
• Grade 0 : No ulceration
• Grade 1 : Superficial ulceration
• Grade 2 : Deep ulceration exposing tendons and joints
• Grade 3 : Extensive ulceration involving bone
• Grade 4 : Gangrene
• Grade 5 : Extensive necrosis of foot

7. Classification of ulceration
• Wagner grade 0 foot:
Diabetic foot without ulceration but with one or more
risk factors such as bony deformities, atrophic fat pad, plantar
flexed metatarsals, PVD and Charcot joint disease.

8. Management of grade 0 foot:
• Education and prevention
• Good glycemic control.
Prevention includes shoe-gear modification, Debridement of
corns and calluses, proper nail and skin care, use of
moisturisers.
Important aspect of preventive self care is inspection of feet
daily.

9. Grade 1 foot :
• Grade 1 ulceration implies presence of peripheral sensory
neuropathy and at least one other risk factor such as bony
deformities, plantar flexed metatarsals with distally
displaced fat pad, limited joint mobility or ill fitting shoes.
• It extends to the dermis but not beyond.
• Treatment :
Soft tissue debridement , off-loading , Daily dressings

10. Grade 2 foot :
• Failure to adequately off-load grade 1 lesions lead to
deepening ulcerations beyond the level of dermis.
• Deeper structures such as tendons or joint capsule may be
involved.
• Bone, joint or tendon involvement might require
hospitalization, complete bed rest, surgical debridement and
broad spectrum iv antibiotics (Choice of antibiotic should be
based on deep cultures taken at the time of debridement)

11. Grade 2 foot contd…
• First generation cephalosporins are often a good choice as
they provide broad spectrum coverage and good coverage
against staphlococci.
• After debridement, an arteriogram and lower extremity
revascularization should be performed in the ischemic
limb.
• Radiographs should be performed in long standing full
thickness ulceration to evaluate for osteomyelitis.

12. Grade 3 foot :
• Grade 2 ulceration that has not responded to local care or
been neglected.
• These ulceration involve bone and therefore require
surgical debridement and reconstructive surgery.

13. Grade 4 foot :
• Gangrenous change in lower extremity can occur in 2
ways:
• When gangrene results from arterial insufficiency,
revascularization should be performed. DSA is used to
assess the level of revascularization. Once
revascularization has been performed, an amputation at the
most distal level should be performed.
• If infection is the primary cause, selection of an
appropriate antibiotic and aggressive debridement with
adequate I &D is the treatment of choice.

14. Grade 5 foot :
• Extensive necrosis of the foot
• Treatment – Primary amputation

15. Charcot joint disease:
• 1 in 680 patients with diabetes have Charcot joint disease.
• Presents as unexplained swelling and erythema of the
foot.
• Profound sensory neuropathy makes this a painless
process.
• Most common location is the tarsometatarsal articulations.

16. Treatment:
• Non-surgical therapy:
-Immobilization
-Reduction of stress (non-weight bearing)
-Medical management :
Bisphosphonates inhibit osteoclastic inhibitions and also inhibit
bone destruction by increasing apoptotic death of macrophages and have
direct anti-inflammatory properties.
Alendronate 70 mg once weekly for 6 months
(or)
Zolendronate 4 mg once a month for 12 months
-After cast removal, patients should wear a brace to protect the foot.

17. Selection of footwear:
• Accommodate, stabilize and support
deformities.
• Insole should be able to redistribute the plantar pressures
evenly and reduce shock and shear forces.
• Back strap or heel counter for support.
• Wide toe box
• Depth of the toe box should be adequate to allow room
for the toes to extend and flex minimally without any
pressure.

18. • A rigid outsole for protection from sharp objects.
• Slip on foot wear without heel counter or back strap are
to be avoided as they can lead to corns and calluses by
causing the tips of toes to rub on the shoe.
• T straps are also to be avoided as they can cause
ulceration in the first web space.

19. Diabetes maintenance therapy for vascular disease prevention :
• Blood glucose control :
Target HBA1c : < 7 gm%
Target premeal values : 80-120 mg/dl
Bed time values : 100-140 mg/dl
• BP control :
Target : <130/80 mm Hg
ACE inhibitor is the anti-hypertensive of choice
• Blood lipid control :
Target LDL : <100 mg/dl
Target TG : <150 mg/dl

20. • Antiplatelet therapy:
-Aspirin for primary prevention if age >50 ys in men or
>60 yrs in women who have atleast 1 additional major risk
factor.
-Clopidogrel
-Platelet IIb/IIIa inhibitor
• Miscellaneous:
-Smoking cessation
-Foot care program

21. Diabetic foot infections
Compromise of the blood supply from microvascular
disease, often in association with lack of sensation
because of neuropathy, predisposes persons with diabetes
to foot infections.
They typically take one of the following forms:
• Cellulitis
• Deep-skin and soft-tissue infections
• Acute osteomyelitis
• Chronic osteomyelitis

22. • Infections in patients with diabetes are difficult to treat
because these individuals have impaired microvascular
circulation, which limits the access of phagocytic cells to
the infected area and results in a poor concentration of
antibiotics in the infected tissues.
• Superficial skin infections, such as cellulitis, are caused
by group A streptococci and Staphylococcus aureus.
• Deep soft-tissue infections in diabetic persons can be
associated with gas-producing, gram-negative bacilli.

23. Management:
• Good glycemic control
• Off-loading
Mild infections oral antibiotics that cover Streptococci
and Staphylococcus aureus.
• Agents such as cephalexin, amoxicillin-clavulanate, or clindamycin
are effective choices.
• If MRSA infection is suspected, then clindamycin, trimethoprim-
sulfamethoxazole, minocycline, or linezolid may be used.
• If gram-negative aerobes or anaerobes are suspected, dual drug
treatment with trimethoprim-sulfamethoxazole plus amoxicillin-
clavulanate or clindamycin plus a fluoroquinolone such as
levofloxacin or moxifloxacin may be used.

24. • Moderate-to-severe infections parenteral antibiotic
therapy.
• Empiric choices should cover streptococci, MRSA,
aerobic gram-negative bacilli, and anaerobes.
• MRSA is covered by vancomycin, linezolid, or
daptomycin.
• Acceptable choices for gram-negative aerobes and
anaerobes include ampicillin-sulbactam, piperacillin-
tazobactam, meropenem.

25. • For those treated with oral antibiotics, duration of
treatment is usually 7-14 days.
• In those treated parenterally but without osteomyelitis, 2-4
weeks is sufficient.
• Longer duration of therapy is required for those with
osteomyelitis—4-6 weeks at a minimum.
• Surgical debridement might be required in case of
osteomyelitis.

27. • Intertrigo (Inflammatory condition of skin folds)
Due to moisture and sweat; Poor hygiene

29. • Charcot’s foot

31. • Erysipelas of the ankle, with a large
purulent serosity-filled bulla

33. • Severe ischemic necrosis of the foot
consecutive to severe infection

35. • Gas gangrene

37. • Osteomyelitis of distal phalanx

39. • Dislocation of foot skeleton architecture
-Typical aspect of Charcot’s foot

40. • References:
• Joslin’s Diabetes mellitus
• A practical guide to DM – Nihal Thomas
• Harrison’s principles of internal medicine
• Medicine update 2016

41. Thank you