Hi, 1) Here is what you mean by PERTHES diseases- Its a diseases where the blood supply to the hip bone gets blocked, not the bone with out the nutrients and oxygen can t remain alive so it starts getting to the point where it slowly the tissue starts dying and its knows as NECROSIS (Fancy word for death of cells) it will cause a lot of pain and for that you were prescribed traumadol. 2) Ok now about GALL BLADDER - it acts as reservoir for the bile which is produced by liver, now bile is released as per need from the liver and excess is stored in gall bladder during process of digestion. (Gall bladder is a organ which is like a bottle which has one opening where it has two straws one duct{straw/pipe} bring the bile from liver to gallbladder and other from gallbladder to intestine) 3) Now about the TRAMADOL - Its pain medication which decreases pain but the side effects is it will cause the duct opening to be narrow/constricts them, hence lies the problem of the gall bladder stone. LET ME EXPLAIN - Have you seen, how salt is made from the sea water? Water is evaporated by sun s heat living the white crystals of salt. In same way if the bile is coming in but the bile can t go out from the gall bladder what happens ? body starts absorbing the water from bile juice so it will turn into as crystal like structure similar to salt crystal formation when water is taken off, hence the person taking tramadol has chances for getting gall stone which occurred in your case. HERE IS THE ANSWER FOR YOUR QUESTION: Their is only one gallbladder in human body, you were operated and gallbladder was removed. Now their is no reservoir for the bile, and bile when secreted from the liver is always in syrup like so it has enough water hence from above example you will get an idea that now its impossible to get another stone in future as we need a storage vessel of bile to form crystal/stone and our storage vessel was removed. Hope it helps.