Which ankle-brachial index (ABI) range corresponds to claudication?

Which ankle-brachial index (ABI) range corresponds to claudication?

• A. Greater than 1.0
• B. 0.88 to 0.99
• C. 0.40 to 0.79
• D. <0.40

Answer: (C)

Ankle-brachial index measures how well blood is flowing to the legs by comparing the pressure at the ankle to the pressure in the arm. A normal ABI is around 1.0 or higher; values below 1.0 indicate some narrowing, with lower numbers showing more severe disease. Claudication—pain in the legs with walking due to exertional ischemia—tends to occur when blood flow is reduced enough to limit oxygen delivery during activity but not so severe that pain is present at rest. This pattern is typically seen with PAD in the mild-to-moderate range, roughly from 0.4 to 0.9. Therefore, the range from 0.40 to 0.79 fits the classic presentation of claudication. Values closer to normal (around 0.9–1.0 or higher) usually don’t cause claudication, and very low values (<0.40) are associated with rest pain or critical limb ischemia rather than intermittent claudication.

Ankle-brachial index measures how well blood is flowing to the legs by comparing the pressure at the ankle to the pressure in the arm. A normal ABI is around 1.0 or higher; values below 1.0 indicate some narrowing, with lower numbers showing more severe disease. Claudication—pain in the legs with walking due to exertional ischemia—tends to occur when blood flow is reduced enough to limit oxygen delivery during activity but not so severe that pain is present at rest. This pattern is typically seen with PAD in the mild-to-moderate range, roughly from 0.4 to 0.9. Therefore, the range from 0.40 to 0.79 fits the classic presentation of claudication. Values closer to normal (around 0.9–1.0 or higher) usually don’t cause claudication, and very low values (<0.40) are associated with rest pain or critical limb ischemia rather than intermittent claudication.