acute lower limb ischaemia

Last reviewed 01/2018

Ischaemia in the lower limb may develop acutely as a result of embolism, thrombosis or arterial occlusion by trauma or tourniquets.

Emboli frequently impact at branching points such as the aortic bifurcation - causing a saddle embolus which affects both limbs, the common femoral bifurcation, and the popliteal trifurcation.

Thrombotic occlusion may develop anywhere especially if there is pre-existing atherosclerosis. The consequences are particularly severe if it occurs in the popliteal artery where there are few useful collaterals, the external iliac or common femoral arterial trunk, which is the axial blood supply of the lower limb, or the profunda femoris.

Early diagnosis is vital since infarction can develop within hours unless treatment is instigated.