Building Muscle Surrounding the Patella

How can I build the muscle that surrounds the patella? Two years ago, I ruptured my right patella tendon and since then I cannot build the muscle surrounding the patella. Furthermore, I have a hard time building leg muscle at all, and I do squats on the smith machine as well as leg curls and extensions.

First I would stop doing leg extensions. Second remember there is no muscle structure around the knee and or the patella. You have Your Rectus femoris and other quad muscles in the upper thigh and also the biceps femoris or hamstring muscles. The tendons from these muscles cross over the knee and attach to the Tibia allowing it to flex and extend. I would Try this program since you already do Smith Machine Squats.