π¦Ά Charcot Foot Syndrome (CFS) is one of the most devastating complications affecting patients with diabetes and peripheral neuropathy.
π About
- Neuropathic joint β loss of sensation, so damage may go unnoticed.
- Progressive bone and joint deformity β destructive arthritis π¦΄.
- Associated with a mean reduction in life expectancy of ~14 years β³.
β οΈ Causes (any sensory neuropathy)
- Diabetic neuropathy (most common) π¬
- Tabes dorsalis (syphilis)
- Syringomyelia (upper limbs)
- Alcoholic neuropathy π·
- Cerebral palsy with sensory loss
- Leprosy π¦
- Congenital insensitivity to pain
βοΈ Aetiology
- Neurotraumatic theory: Repetitive trauma + loss of pain/proprioception β bony destruction.
- Neurovascular theory: Autonomic hyperaemia β osteopenia + trauma β joint collapse.
- Intrinsic muscle imbalance β eccentric loading β microfractures, laxity, deformity.
π Clinical Features
- Numbness, redness, swelling (pain only in ~50%).
- Injuries, fractures, deformity π¦΄.
- Peripheral neuropathy (fails 10 g monofilament test).
- Assess arterial perfusion: pulses (palpation/Doppler) π.
π§ͺ Investigations
If acute Charcot arthropathy is suspected β arrange weight-bearing X-ray.
If X-ray is normal but suspicion remains β MRI π₯οΈ.
- Bloods: FBC, U&E, LFT, urate, glucose, HbA1c, CRP (raised CRP β ?osteomyelitis).
- Blood cultures if infection suspected.
- Infrared dermal thermography: >2.0Β°C difference vs contralateral side π‘οΈ.
- Plain weight-bearing radiographs.
- MRI: stress fractures, fragmentation, subluxation/dislocation, osteopenia, osteolysis.
- Indium-111 leukocyte scan for osteomyelitis if unclear.
π Differential Diagnosis
- Osteomyelitis π¦
- Acute gout π¦Άπ₯
- DVT π©Έ
- Deep abscess
- Inflammatory arthritis
πΌοΈ Imaging
π©Ί Management
- Urgent referral: Within 1 working day β multidisciplinary foot service (NICE NG19).
- Immediate: Non-weight-bearing + immobilisation (total contact cast) until resolution.
- Step-down: Gradual partial weight bearing as advised.
- Moderate deformity: Custom footwear + offloading orthotics π.
- Severe deformity: CROW boot; consider surgical referral π οΈ.
- Psychological support + physiotherapy for strengthening πͺ.
- 3-monthly reviews to monitor for reactivation π.
π‘ Exam Tip: In suspected acute Charcot foot, the key is urgent referral + non-weight-bearing.
Confusing it with cellulitis or osteomyelitis is a classic exam trap β‘.
π References