Brief Answer:
The black area is probably due to tissue necrosis (dead tissues) and it can be very painful. Proper local treatment is crucial.

Detailed Answer:
Hello and welcome to "Ask a Doctor" service,

I carefully read your query and also checked the uploaded pictures. The quality of the pictures was not so good but I was able to notice the black area that you refer to.

The presence of black tissue means there is necrosis (dead tissues), which is a possible complication with problems with the arteries of the legs. The black area is also called eschar. It generally needs to be removed to prevent further complications with infection. Removal can be done surgically or with certain bandages that allow it to be degraded and fade away.
Wounds due to arterial insufficiency are generally very painful and especially if necrosis happens, the areas around are painful as well, thus, unfortunately, it is not uncommon to have a lot of pain with this kind of wounds.

It is very important that other than treating the eschar as effectively as possible, to also identify the cause of the wounds and treat it accordingly.

There is not much information provided on the cause of the arterial insufficiency that you are experiencing, but if it is a plaque in the artery, surgery can be done to remove it or surgery to substitute the damaged blood vessels with blood vessels taken from other areas of the body.

To conclude:
- the images uploaded are not very clear but as much as I can see, it seems you are having eschar (dead tissues).
- wounds that originate from arterial insufficiency are generally very painful, this is the reason you are in so much discomfort
- you will need proper treatment of the eschar to prevent infection and worsening of the wound and related serious complication
- the doctor may decide to remove it surgically or use certain bandages to help it be degraded and loosen from the rest of the tissues
- proper treatment of the primary cause of the would is needed as well

I hope this answers your query and is helpful. I remain at your disposal in case further medical assistance is needed.

I wish you a quick improvement.

Regards,
Dr. Antoneta Zotaj, General & Family Physician

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