Patient Knee have pain after 1 year of operation of knee. this operation was due to small accident. all was ok, but few days back pain started, when local orthopedic handled this case, he said no issue, due to water it happen. he removed 15-20 ml water by injection methods and putted some medicine inside . we are worried. what is reason ? why? it may of treatment issue. ? or it is normal ?? or due to inside of iron plate in leg .??