A trial implant system and method of trialling are described. A stem prosthetic implant (320) has a neck bearing a taper (324). A protector (330) covers the taper and is removable from the taper. The protector has a side wall (333 342) and an end wall (335) and the end wall is rigid and an inner surface (346) of the side wall is deformable. A head prosthetic implant (380) has a prosthetic articulating surface (382) and includes a tapered bore arranged to matingly receive the taper therein to form a prosthetic assembly of the stem prosthetic implant and the head prosthetic implant. A head trial implant (310) has a trial articulating surface (312) and including a trial bore (318) arranged to matingly receive the taper covered by the protector therein to form a trial assembly of the stem prosthetic implant and the head trial implant. The trial assembly provides at least a portion of the trial articulating surface coincidental with the prosthetic articulating surface provided by the prosthetic assembly.
