US Patent 9498344 Modular reverse shoulder prostheses

A modular reverse shoulder prosthesis according to embodiments of the present invention includes a stem having a proximal taper and a primary stem axis, the proximal taper extending from the stem about a metaphyseal axis, the metaphyseal axis at an angle with respect to the primary stem axis, a metaphysis having a proximal end, a distal end, a first aperture in the distal end configured to be placed over the proximal taper, and a second aperture in the proximal end having an insert axis that is eccentrically offset from the metaphyseal axis, the metaphysis configured for attachment to the stem at any rotational position of the metaphysis about the metaphyseal axis, and a reverse insert, the reverse insert having a proximal end and a distal end, wherein the proximal end comprises a concave cup formed about a cup axis and configured to receive a glenosphere.