Charcot neuroarthropathy

Charcot neuroarthropathy

; Charcot joint disease; neuropathic osteoarthropathy gross distortion of weight-bearing joints secondary to long-term sensory and autonomic neuropathy, abnormal inflammatory and healing responses; early immobilization for a minimum of 12 weeks is essential to minimize joint distortion; typical of diabetes mellitus and tabes dorsalis (syphilis)

• atrophic Charcot neuroarthopathy; diabetic osteolysis joint destruction characterized by rapid hyperaemic bone resorption (secondary to autonomic neuropathy, abnormal bone blood flow and local periarticular osteopenia) leading to 'pencilling' ('sucked candy stick') of distal metatarsals

• hypertrophic Charcot neuroarthropathy joint destruction characterized by rapid loss of joint architecture (secondary to pain and proprioception loss and local cortical microfractures) and associated disorganized osseous proliferation (due to abnormal bone-healing response) with resultant foot deformity, often of midtarsal or ankle joints (Table 1and Table 2)

Table 1: Classification of Charcot neuroarthropathy

Stage	Characteristics
0	Clinical symptoms only: erythema, oedema, increased temperature (>2°c difference)
I	Developmental: generalized bone demineralization, periarticular fragmentation, loose-body formation, joint dislocation
II	Coalescent: organization and healing of fracture fragments, periosteal new bone formation, resorption of bone debris
III	Reconstruction/consolidation: greater definition of bone contours, reconstruction or ankylosis of involved bone

Table 2: Clinical features of hypertrophic Charcot joint disease

Vascular	Neuropathic	Skeletal	Cutaneous sequelae
Bounding pulses Erythema Oedema Warmth	Lost or reduced: Pain/vibration awareness Proprioception Deep tendon reflexes	'Rocker bottom' foot Midfoot subluxation Digital contracture Hypermobility	Hyperkeratosis Trophic ulceration Secondary infection