A method of implanting a prosthetic stemless shoulder implant may include making an incision into a patient's shoulder area of a patient and passing a cutting instrument through a rotator cuff interval (70) of the patient. A central portion (12) of the native humeral head may be resected and removed so that a central void remains (12'). The same or another cutting instrument may be inserted through the rotator cuff interval and into the central void. Medial and lateral portions (14, 16) of the native humeral head adjacent the central void may be resected and removed. A base (100) of a prosthesis may be implanted into a proximal portion of the humerus after passing the base through the rotator cuff interval, and two humeral head portions (150a, 150b) may be inserted through the rotator cuff interval and coupled to the base and to one another.
