There could be cyst-like masses of different forms and shapes, around the knee.
At the physical examination benign and malignant masses must be distinguish from cystic lesions.
Cystic lesions could be ganglion cyst, meniscal cyst, intraneural cyst, vascular cyst, bursa cyst.
Some of knee cysts can be related to systemic diseases like rheumatoid arthritis and osteoarthritis affecting the knee.
The cysts you have are most likely inflamed bursa (small sac that provide cushion between bones and tendons or muscles around the joint).
It is well known that at the anterior side of knee joint are situated four of these bursa.
Due to irritation they can get inflamed and painful.

Only complete evaluation can give you a correct diagnosis.

Best wishes!
Marija