What causes reddish ring on right hip?

Brief Answer:
May be ring worm (tinea corporis) but need to see a pic to confirm.

Detailed Answer:
Hello and welcome,

A red ring on the skin is most likely ring worm. However, if it looks like a bull's eye type ring, there is the possibility of Lyme disease from a tic bite. Ring worm is a fungal infection and would not cause aches - if it were ring worm the aches in the back and hip would be from a separate cause. But Lyme disease can be associated with joint pain.

Have you had any fevers?
Been in any wooded or high grass areas?
How long have you noticed the red rings?
How long have you had the dull ache?

And most importantly - can you upload some high quality pictures?

Thanks - more information to follow.

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