summary Diabetic Foot Ulcers are very common lower extremity wounds that occur in diabetics with peripheral neuropathy and are responsible for 85% of lower extremity amputations. Diagnosis is made clinically with presence of a plantar foot ulcer which may probe to bone. MRI studies are useful to assess for presence and extent of osteomyelitis. Treatment depends on ulcer size, ulcer thickness, ulcer location and presence of concomitant infection. Epidemiology Incidence approximately 12% of diabetics have foot ulcers most common medical complication causing diabetics to get medical treatment foot ulcers are responsible for ~85% of lower extremity amputations Risk factors factors associated with decreased healing potential uncontrolled hyperglycemia (Hb A1C > 8.0) inability to offload the affected area poor circulation infection poor nutrition factors associated with increased healing potential serum albumin > 3.0 g/dL total lymphocyte count > 1,500/mm3 modifiable risk factors for prevention of amputation smoking glycemic control Etiology Pathophysiology neuropathy has largest effect on diabetic foot pathology sensory dysfunction leads to lack of protective sensation and is primary risk factor for ulcer development autonomic dysfunction leads to drying of skin due to lack of normal glandular function net effect is increased mechanical and axial stress on skin that is more prone to injury due to drying angiopathy lesser effect than neuropathy >60% of diabetic ulcers have decreased blood flow due to peripheral vascular disease Associated condition infection / osteomyelitis high rates of associated osteomyelitis if bone is able to be probed, or is exposed at the base of the ulcer login to view 1 more bullet organisms usually polymicrobial gram-positive login to view 1 more bullet gram-negative login to view 1 more bullet anaerobes login to view 1 more bullet deep cultures and bacterial biopsies help guide management and remain gold standard for diagnosis Classification Wagner Classification and Treatment Description Treatment Grade 0 Skin intact but bony deformities lead to "foot at risk" Shoe modifications with serial exams Grade 1 Superficial ulcer Office debridement and contact casting Grade 2 Deeper, full thickness extension Operative formal debridement and contact casting Grade 3 Deep abscess formation or osteomyelitis Operative formal debridement and contact casting Grade 4 Partial Gangrene of forefoot Local vs. larger amputation Grade 5 Extensive Gangrene Amputation Brodsky Depth-Ischemia Classification and Treatment Depth Classification Definition Treatment 0 At risk foot, no ulceration Patient education, accommodative footwear, regular clinical examination 1 Superficial ulceration, not infected Off-loading with total contact cast, walking brace or special footwear 2 Deep ulceration, exposing tendons or joints Surgical debridement, wound care, off-loading, culture-specific antibiotics 3 Extensive ulceration or abscess Debridement or partial amputation, off-loading, culture-specific antibiotics Ischemia A Not ischemic B Ischemia without gangrene Non-invasive vascular testing and vascular reconstruction with angioplasty/bypass C Partial forefoot gangrene Vascular reconstruction and partial foot amputation D Complete gangrene Complete vascular evaluation and major extremity amputation Presentation Symptoms often painless Physical exam depth of ulcer probe for bone presence of infection look for cellulitis, pus check for gangrene assess Achilles tendon tightness Silverskiöld test login to view 2 more bullets circulation assess dorsalis pedis and posterior tibialis pulses Studies Transcutaneous oxygen pressures (TcpO2) considered Gold Standard to assess wound healing potential > 30 mm Hg (or 40mmHg depending on review source cited) is a good sign of healing potential ABI's and ischemic index calcification in the arteries can result in inaccurate doppler flow readings calcifications falsely elevate the ABI's due to decreased compliance of the calcified vessels index of > 0.45 and toe pressure >45mm Hg are needed to heal amputation and >60mm Hg to heal an ulcer Imaging Radiographs recommended views AP, lateral, and oblique of foot and ankle MRI best for differentiating abscess from soft tissue swelling difficult to differentiate infection from Charcot arthropathy on MRI Bone scan views obtain with technetium Tc99m, gallium (Ga)67, or indium (In) 111 useful to differentiate between soft tissue infection osteomyelitis Charcot arthropathy Treatment General factors important in deciding a treatment plan include angiopathic vs. neuropathic deep vs. superficial +/- osteomyelitis, antibiotics based on bone biopsy culture sensitivities +/- pyarthrosis Nonoperative shoe modification indications login to view 1 more bullet includes deep or wide shoes, custom insoles, rocker bottom soles, etc. of the available shoe only modifications, rocker sole shoes best reduce the plantar pressure on the forefoot medicare will cover modifications and custom shoes/insoles yearly wound care indications login to view 1 more bullet goals of wound care and dressings login to view 4 more bullets total contact casting (TCC) indications login to view 1 more bullet contraindications login to view 6 more bullets outcomes login to view 1 more bullet negative pressure wound therapy reduces time to healing and ulcer size Operative Flexor tendon tenotomy indications login to view 1 more bullet outcomes login to view 1 more bullet surgical debridement, antibiotics, contact casting +/- gastroc recession/TAL indications login to view 1 more bullet outcomes login to view 2 more bullets ostectomy +/- TAL indications login to view 1 more bullet technique login to view 2 more bullets partial calcanectomy +/- TAL indications login to view 1 more bullet outcomes login to view 1 more bullet Syme amputation indications login to view 1 more bullet Keller resection arthroplasty indications login to view 1 more bullet Techniques Total Contact Casting often necessary for up to 4 months TCC followed by Charcot restraint walker then custom shoe pneumatic walking brace alternative to TCC, same principal allows better wound surveillance significant deformity and/or extremely large girth often requires custom pneumatic walkers patient compliance with offloading can be an issue because the pneumatic walker is removable Prognosis Diabetic foot ulceration is considered the most likely predictor of eventual lower extremity amputation in patients with diabetes mellitus