A method of treating a hip joint of a human patient using a pelvic drill comprising a driving member, a bone contacting and an operating device for operating said driving member. The method comprise the steps of creating a hole passing through the pelvic bone and into the hip joint of the human patient, and providing at least one hip joint surface to the hip joint, through said hole in the pelvic bone of the human patient. In one embodiment the method includes inserting a needle or tube like instrument into the patient's body for filling a part of the patient's body with gas and thereby expanding a cavity within the body.