An implant or endoprosthesis suitable to be implanted in human or animal tissue includes two (or more than two) parts to be joined in situ. Each one of the parts includes a joining location, the two joining locations facing each other when the device parts are positioned for being joined together, wherein one of the joining locations includes a material which is liquefiable by mechanical vibration and the other one of the joining locations includes a material which is not liquefiable by mechanical vibration and a structure (e.g. undercut cavities or protrusions) suitable for forming a positive fit connection with the liquefiable material. The joining process is effected by pressing the two device parts against each other and by applying ultrasonic vibration to one of the device parts when the two parts are positioned relative to each other such that the two joining locations are in contact with each other.

A surgical instrument for operating hip joint osteoarthritis in a human patient is provided. The hip joint comprises an acetabulum, being a part of the pelvic bone, and a caput femur, being the proximal part of the femoral bone. The surgical instrument is adapted to assist in the operating of the hip joint osteoarthritis from the abdominal side of the pelvic bone of said human patient.

A medical device for delivering an action to an area of a hip joint or its surroundings, inside a human body, is provided. The hip joint of a patient comprises a collum femur and a ball shaped caput femur, being the proximal parts of the femoral bone, and an acetabulum, being a bowl shaped part of the pelvic bone. The medical device comprising; an elongated member, having a length axis along its elongated distribution, comprising a first portion, adapted to enter the body of the patient, and a mechanical element, adapted to be used during an operation in the hip joint or its surroundings, inside the body. The first portion of the elongated member comprises a holding member adapted to hold the mechanical element inside the body of the patient, wherein the first portion of the elongated member have a first portion cross-section area substantially perpendicular to the length axis of the elongated member. The first portion is adapted to pass through a hole, in a bone of the patient, the hole having a hole cross-section area. The first portion cross-section area, is adapted to be smaller than said hole cross-section area. The mechanical element have a functional status, ready to deliver said action inside said body, when held by the holding member inside the body of the patient. The mechanical element is adapted to have a mechanical element cross-sectional area substantially perpendicular to the length axis of the elongated member, substantially larger than the first portion cross-sectional area and adapted to be unable to pass through the hole, when the mechanical element is in the functional status.

A femoral head arthroplasty system can comprise a femoral prosthesis comprising a mounting plate having a first side and an opposed second side. An adapter can extend from the second side of the mounting plate. An implant body can extend from the first side of the mounting plate. The implant body can extend from the mounting plate by a distance no greater than 90 mm. The femoral head arthroplasty system can further comprise a femoral head replacement having a generally spherical surface and comprising a recess that is shaped to complementarily receive the adapter of the femoral prosthesis.

A medical device for implantation in a hip joint of a human patient is provided. The natural hip joint having a ball shaped caput femur as the proximal part of the femoral bone with a convex hip joint surface towards the centre of the hip joint and a bowl shaped acetabulum as part of the pelvic bone with a concave hip joint surface towards the centre of the hip joint. The caput femur has a centrally placed longitudinal extension, extending through the center of the caput and collum femur, aligned with the collum femur, defined as the caput and collum femur center axis. The medical device comprising; an artificial acetabulum, comprising a concave surface towards the centre of the hip joint. The artificial concave acetabulum is adapted to, when implanted, be fixated to the femoral bone of the human patient, and be in movable connection with an artificial caput femur fixated to the pelvic bone of the patient.

A method for fixating an artificial convex caput femur surface to the pelvic bone of a patient, the method comprising the steps of: exposing the acetabulum surface, creating a hole or recess in the pelvic bone from the acetabulum side of the pelvic bone, providing the artificial convex caput femur, comprising an elongated member to the hip joint, inserting said elongated member in said hole, and performing an action on the acetabulum side of the pelvic bone such that the elongated member is structurally changed on the abdominal side of the pelvic bone or inside the pelvic bone.

A medical device for fixation in a femoral bone of a patient is provided, the medical device comprises: a connecting portion adapted to be connected to a prosthetic hip joint contacting portion, an expanding portion, and a bone contacting surface on the expanding portion. The expanding portion could be adapted to be at least partially inserted into the femoral bone of a patient and to expand within the femoral bone, such that the bone contacting surface is placed in contact with the inside of the femoral bone for fixating the medical device to the femoral bone. By the fixation using an expanding portion a sturdy fixation is achieved without the need to go into or penetrate bone, or the need for fixation using bone cement.

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 cutting the skin of the human patient, dissecting an area of the pelvic bone on the opposite side from the acetabulum, creating a hole in said dissected area using said pelvic drill, said 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.

An implantable medical device for implantation in a hip joint is provided. The medical device comprises: at least one artificial hip joint surface adapted to replace at least the surface of at least one of the caput femur and acetabulum. At least one artificial hip joint surface comprises: a positioning hole with at least one opening in said at least one artificial hip joint surface. The hole is adapted to be placed and dimensioned such that the medical device is adapted to be fitted using a positioning shaft and at least partly surround the shaft, for positioning the at least one artificial hip joint surface in a desired position in the hip joint. The hole is adapted to be fitted using the positioning shaft, when the shaft is stabilized and placed in at least one of the femoral bone and the pelvic bone for positioning said medical device inside the hip joint.

A method for implanting a medical device for lubricating a joint in a human body, said method comprising the steps of creating an opening reaching from outside of the human body into the joint, providing an artificial contacting surface to said joint, fixating the artificial contacting surface to the joint, implanting a reservoir in the human body, and lubricating said artificial contacting surface by pressurizing a lubricating fluid contained in said reservoir.