A femoral head resurfacing implant is described comprising an external articulating surface and an internal fixation surface. A stem projects from the center of the internal fixation surface. The internal fixation surface comprises a top surface, surrounding and substantially orthogonal to a long axis of the stem, a chamfer surface extending downwardly and outwardly from the top surface and a side surface extending substantially parallel to the long axis of the stem. At least one projection is arranged on the internal fixation surface to provide a predetermined gap between the top surface and/or chamfer surface and a resected head onto which the implant is to be fitted. Furthermore, the side surface constitutes or comprises a cement containment feature configured to restrict or eliminate outflow of cement from the predetermined gap.