Brief Answer:
Either patellofemoral pain syndrome or patellar tendon injury

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. The pain described by you is in or around the region between the patella (knee cap) and the tibial bone.

In my opinion, the pain is either related to a condition called patellofemoral pain syndrome or something to do with the patellar tendon which is attached to the patella (knee cap) on one end and the tibial tubercle on the other.

Either way sir, the causes are mostly:

+In athletes and other people who run often
+Improper running gear used
+Overuse

A physical examination and x-ray examination of the affected knee joint will be required and so I would recommend a visit to a doctor as we can only do so much through an online consultation. But if you can establish a link with the causes, then the first thing you need to stop doing would be obvious.

A few other suggestions other than the rest and elevation you have tried include:

+Ice application
+Elastic compressive bandage
+Use of non-steroidal anti-inflammatory medications (e.g. ibuprofen, tylenol, etc.)
+Lose weight if you are overweight
+Go ahead with some low impact exercises to help strengthen the region (e..g swimming)
+Avoid putting too much weight on the affected leg

I hope you find my response both helpful and informative. Please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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