Brief Answer:
Need not be caesarean related

Detailed Answer:
Hi madam,
I can understand your concern.
Normally, pain in the knee joints is not related to pregnancy nor to any type of delivery - normal vaginal or caesarean section. However, it is a condition when the body's power to resist the diseases (immunological response) goes down and then the otherwise subdued conditions prop up.
Did you have any infection, particularly throat infection for a long time? That can cause Rheumatic disease in which fleeting joint pain is characteristic.
The other type of arthritis is rheumatoid arthritis. However it starts in smaller joints and runs in the family. Do you have any family history of rheumatoid arthritis? I would advise you to get RA factor test done on your blood. This will reveal whether you are having rheumatoid arthritis.
Do you remember over spreading of the joints during delivery? Was it a planned caesarean or done for failed labour? If so, did you hurt your knee in the labour?
Did you have any trauma to your knee joint - recent or past? This may come up during or after pregnancy.
X-ray of the knee joint will throw some light on the diagnosis.
Also get your blood tested to see whether there is any anaemia and/or evidence of any infection.
Whatever the cause and the report, you will have to get checked up from the orthopaedic specialist.
Till that please give due rest to the knee joint till the diagnosis is confirmed. Do not foment till the diagnosis is not confirmed.
If you send me the reports of your blood and x-rays of the knee joint in front and side views, I can suggest you further.
I feel, in such an early stage of this ailment, mostly the physiotherapy will give you some relief. Please send me the reports and I may suggest you certain exercises which can give you some relief.
I hope this has give you preliminary guidance about your condition.
You may ask some more queries about this along with your reports so that we can discuss further.

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