Brief Answer:
Need workup for unilateral large joint arthritis with pedal oedemas

Detailed Answer:
Hi! Welcome to health care magic!

Based on your history of left knee arthropathy and plica or synovial membrane sweeping or inflammation with in the knee for which you are going to have surgery very soon, so such association with a large joint involvement in such young age is another detailed evaluation in its own to find the possible cause and now it's relation to swelling in legs and feet can't be ignored as isolated entity but it raises suspicion of variety of possibilities.

Possible causes of leg swelling aka pedal edema like is shown in picture, include renal disease, liver disease, cardiac diseases, and lymph drainage surgeries. Don't get panicked at larger names as these can turn out to be normal and nothing is conclusive before undergoing basics labs like urinalysis for protein leak and renal function tests for creatinine and urea levels, liver function tests alongwith albumin levels for protein synthesis and determination of normal livers functional ability alongwith cardiac echo cardiography to look for pumping ability aka ejection fraction of the heart. These all are pretty basic tests which can be done in small clinical setups and can reveal alot of information regarding such causes in your case.

Association of renal or liver diseases can be due to excessive use of anti inflammatory drugs or pain killers or can be due to possibility of a primary disease which can involve both joints and any such organ. For that RA factor and ANA can be run to rule out rheumatological diseases.

For all this excessive workup, I would urge you to consult your GP and run all these labs at the earliest.

Hoping you a speedy recovery. If you have any more questions, feel free to ask else kindly close the discussion. You can also reach me directly through my profile in future, in case of any more queries. Keep me apprised of the situation. Regards.

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