Classification
Rutherford’s Classification
It is most important to decide whether the leg is viable, threatened or irreversibly ischaemic.
The purpose of the history and examination is to determine three things:
- Is the leg acutely ischaemic? (Or is there an alternative diagnosis?)
- Is the likely cause embolic or thrombotic?
- Is the leg viable, threatened or irreversibly ischaemic?
The answers to these three questions will determine the immediate management. It is not always possible to distinguish between embolic and thrombotic aetiology, since many patients with an embolic cause may also have some underlying peripheral arterial disease by virtue of their age (15-20% of patients >70 years old have peripheral arterial disease [4]). It is most important to decide whether the leg is viable, threatened or irreversibly ischaemic (See Table 2).
| Capillary return | Motor | Sensory | Arterial Doppler signal | Venous Doppler signal | |
|---|---|---|---|---|---|
| I – Viable | ? | ? | ? | ? | ? |
| IIa -Threatened
(salvageable if promptly treated) |
Intact/slow | ? | Partial (toes only) or none | ?(often) | ? |
| IIb – Threatened
(salvageable with immediate reconstruction) |
Slow/absent | Partial paralysis | Partial(more than toes) or complete | ?(usually) | ? |
| III – Irreversible
(major tissue loss or permanent nerve damage inevitable) |
Absent plus staining |
? Profound paralysis (rigor) |
?Profound (anaesthetic) | ? | ? |
Learning bite
Sensorimotor deficit helps identify limbs in need of urgent intervention. Fixed staining and profound paralysis are signs of irreversible ischaemia.
