The present application relates to an artificial joint implant comprising a first element with a socket and a second element with a ball head. The socket is at least hemispherical and said ball head is inserted in said socket such as to form a ball-and-socket connection between said first element and said second element. Movement of said ball head in said socket is restricted in at least one degree of freedom by means of a at least one protrusion engaged in a at least one groove, wherein said at least one protrusion is provided on said socket and said at least one groove is provided on said ball head or vice versa.