I have SLE Lupus. I have two spinal syovial cysts now and another one on my right side between (or on) my ribs. The spinal cysts are causing a lot of pain and my doctor has referred me for an MRI for my spine. My question is why does the cyst on my ribs throb like a heartbeat? Honestly, that s the only way I can describe it. It actually causes me to jump at times because that pain is so shocking and so intense, then subsides and then happens again. Thank you.