Neuropathic and Diabetic Foot Wounds
Why the diabetic foot ulcerates
Sensory neuropathy removes protective pain, motor neuropathy creates deformity and high plantar pressure (hammer toes, prominent metatarsal heads), and autonomic neuropathy dries and fissures skin. Add ischemia and hyperglycemia-impaired immunity, and a callus becomes an ulcer, most often plantar at metatarsal heads, hallux, or heel.
Assessment
Test sensation with a 10-g monofilament plus vibration and proprioception, palpate pulses, measure ABI or toe pressures, inspect footwear and between toes, and probe the wound. A positive probe-to-bone markedly raises the odds of osteomyelitis. Classify depth (Wagner or University of Texas systems track depth, infection, and ischemia). Debride callus and necrosis once perfusion allows, and obtain imaging when bone is suspected.
Offloading
The total contact cast is the gold standard for a neuropathic plantar ulcer; a removable cast walker makes adherence harder to guarantee. Non-plantar or ischemic wounds need individualized devices. Never cast an infected, ischemic, or unexamined foot.
Charcot
Acute Charcot is red, hot, and swollen and is often mistaken for cellulitis or deep vein thrombosis; early radiographs may be normal. Offload immediately and refer.
Education and traps
- Barefoot walking, heating pads, and soaking are prohibited.
- Daily self-inspection and well-fitting therapeutic shoes prevent recurrence.
- Do not debride without adequate perfusion.
- Do not label a foot neuropathic without documented sensory testing.
Rule of thumb
Probe to bone equals treat as osteomyelitis until proven otherwise. A plantar ulcer over the first metatarsal with a gritty positive probe needs offloading, callus debridement, and urgent imaging and referral, not just a dressing change.