Pathogenesis

1. Collagen vascular disease - infiltration of plasma cells into arterialwall
2. Leads to luminal thrombosis and affects small - medium sided arteries of the lower limb
3. Eventually collagen deposited and forms thick fibrous coat
4. Assocations: heavy smoking 

Approach

• Expose limb

1. Inspect

   

   • Nicotine staining of fingers
   • Chronic paronychia / early ulcers that heal poorly
   • (may be history of intermittent claudication)
   • Distal gangrene and other appearances of chronic ischaemia in the feet, and erythema nodosum
   • Patients have multiple amputations
2. Palpate
   • Proximal pulses present
   • Distal pulses absent

Investigations

1. Collagen antibodies (45% patients)
2. HLA-B5
3. Angiography has typical appearances of normal proximal vessels with distal occlusion and "corkscrew" collaterals