Shoulder arthroplasty implant system

A shoulder arthroplasty implant comprising:

• a stem having a proximal portion, a distal portion, an anterior portion, a posterior portion, a medial portion, and a lateral portion, wherein the stem has a size and shape for insertion into an intramedullary canal of a humerus bone;
• and
• a plurality of fins extending radially outward from the outer surface of the stem, the plurality of fins comprising a medial fin extending outward from the medial portion and a lateral fin extending outward from the lateral portion, each of the plurality of fins being configured to engage cancellous bone in a metaphysis or epiphysis of the humerus bone to provide rotational stability to the stem;
• wherein the distal portion comprises a distal taper decreasing in size in a direction extending from the proximal portion toward the distal portion;
• wherein a lateral surface of the distal taper comprises a convex lateral curve extending in a direction from the proximal portion toward the distal portion;
• wherein a medial surface of the distal taper comprises a concave medial curve extending in a direction from the proximal portion toward the distal portion;
• wherein the distal portion comprises a medial-to-lateral taper, such that an anterior-posterior width of the medial fin is greater than an anterior-posterior width of the lateral fin.