Disclosed herein are components of a reverse shoulder prosthesis. In an embodiment, a reverse shoulder prosthesis includes a humeral adapter tray configured to sit near a resected surface of a humerus, the humeral adapter tray comprising: a cavity; a central bore; and a distal face including a boss, the boss: (i) configured as an extension of the distal face, (ii) posteriorly offset from the central bore by at least 10 mm, and (iii) configured to engage a humeral stem; and a humeral liner comprising: a distal rim configured to sit within the cavity of the humeral adapter tray; and a concave articulating surface configured to mate with a convex articulating surface of a glenosphere. In an embodiment, the boss, in addition to being posteriorly offset, is superiorly offset from the central bore by at least 8 mm. In an embodiment, the reverse shoulder a humeral stem which engages the boss.