I read there's a specific type of cyst for the shin-calf area , not sure exactly where yours is
A popliteal cyst, also called a Baker's cyst, is a soft
, often painless bump that develops on the back of the knee
. A cyst is usually nothing more than a bag of fluid. These cysts occur most often when the knee is damaged due to arthritis, gout, injury, or inflammation in the lining of the knee joint.