2 doctors weighed in:

Why do my knees turn purplish reddish and hurt me?

2 doctors weighed in
David Bracho
General Practice
1 doctor agrees

In brief: Likely Hemarthrosis

These symptoms may be those of a hematoma (bruising) or a hemarthrosis, bleeding into a joint.
By far the most common cause is trauma but could also be a coagulopathy, or decreased ability to form a clot. If there is very little to no trauma or the bruising is severe/painful you should have your doctor check your knees and most likely run some blood test for clotting or sign's or arthritis.

In brief: Likely Hemarthrosis

These symptoms may be those of a hematoma (bruising) or a hemarthrosis, bleeding into a joint.
By far the most common cause is trauma but could also be a coagulopathy, or decreased ability to form a clot. If there is very little to no trauma or the bruising is severe/painful you should have your doctor check your knees and most likely run some blood test for clotting or sign's or arthritis.
David Bracho
David Bracho
Answer assisted by David Bracho, Medical Student
Thank
Dr. Payam Rafat
Podiatry

In brief: Many possibilities

Most likely it is due to overuse, but it could be due to a lot of different reasons.
Knee pain can be due to gout, infection, or due to tendon, cartilage, or bone abnormalities. Have it evaluated by a professional and get the appropriate treatment.

In brief: Many possibilities

Most likely it is due to overuse, but it could be due to a lot of different reasons.
Knee pain can be due to gout, infection, or due to tendon, cartilage, or bone abnormalities. Have it evaluated by a professional and get the appropriate treatment.
Dr. Payam Rafat
Dr. Payam Rafat
Thank
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