Brief Answer:
There is narrowing of lumen in blood vessels supplying the lower limbs

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. The ICD9 system classifies the condition 440.21 as Atherosclerosis of native arteries of the extremities with intermittent claudication

2. In this condition, there is decrease in the lumen of the arteries of the lower limbs probably due to plaque formation along the walls and this causes reduced flow of blood resulting in decreased blood supply.

3. Due to the reduced blood supply to the limbs, there is pain and fatigue after walking a variable distance.

4. Treatment for this condition usually includes cessation of smoking, doing exercises regularly, medicines to open up the blocked arteries and blood thinners and lipid lowering agents.

5. Invasive methods like angioplasty and vascular surgery are less commonly used

Hope your query is answered.
Please do write back if you have any doubts.

Regards,

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