possibly but could also be due to "soft tissue" issues with the ligaments muscles etc. there is also something called a baker's cyst that can form behind the knee that might cause these symptoms.
i have pain in my knee under the knee cap the back of my knee and my thigh is this just arthritis? . some times i can hardly stand i have always tucked my leg under me when i sit down i can't any more the pain is too harsh. some times my thigh muscles and calf muscles hurt so bad is this all part of arthris?