A medical device for implantation in a hip joint of a human patient. The natural hip joint having a ball shaped caput femur (5) as the proximal part of the femoral bone (7) with a convex hip joint surface towards the centre of the hip joint and a bowl shaped acetabulum (11) as part of the pelvic bone (9) with a concave hip joint surface towards the centre of the hip joint. The medical device comprises an artificial caput femur (112), comprising a convex surface towards the centre of the hip joint. The artificial convex caput femur is adapted to, when implanted be fixated to the pelvic bone of the human patient. The artificial convex caput femur is further adapted to be in movable connection with an artificial acetabulum surface (1340) fixated to the femoral bone of the patient, thereby forming a ball and socket joint. The medical device further comprises a fixation element (1311) adapted to engage the surface of the abdominal side of the pelvic bone, for fixating the medical device to the pelvic bone.
