Brief Answer:
Need more details...

Detailed Answer:
Hi,

I need more details to help you here.

May I know your age?
Is the pain present on both side or one knee?
How long has the pain been?
Do you notice swelling or other local skin changes?
Is the pain present through out the day?
Do you notice any factors that aggravates or reduces pain?
Do you notice stiffness of knee?
Are you able to walk?
Did you sustain an injury?

These are the minimum details necessary to understand the cause. Try and answer all the questions.

Awaiting your response...

Regards

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