The tendons are wrapped in a covering that secretes a lubricating, nourishing fluid called synovia. When you move your hand, each tendon slides inside its sheath. Each joint also has a lubricating cover around it called a joint capsule. Ganglion cysts are diagnosed easily, as they are visible and pliable to touch. It looks like a sac of liquid. Inside the ganglion cyst is a thick, sticky, clear, colorless, jellylike material. Depending on the size, cysts may feel firm or spongy.