Humeral head implant system
A humeral head implant system includes a head component including a first articulating surface, a second bottom surface extending from the first spherical articulating surface, a first cavity extending a first distance into the head component from the second bottom surface, and a second cavity extending into the head component along a cavity axis. The head component defines a head axis extending through a center of the first articulating surface parallel to the cavity axis. A base component defines a slot extending from a first width to a second width. An insert component includes an insert body, a first engagement feature, and a slot engagement feature. The first engagement feature is received in the second cavity along the cavity axis. The insert body has an insert thickness less than the first distance, and the slot engagement feature slides into the slot in a direction transverse to the cavity axis.
1 . A humeral head implant system comprising:
a humeral head component including a proximal convex articulating surface configured to articulate in a shoulder cavity, and a distal surface opposite the proximal convex articulating surface, a rim projecting distally from the distal surface of the humeral head component, a head cavity extending from the distal surface toward the proximal convex articulating surface;
an adapter component having a proximal adapter surface and a distal adapter surface, the proximal adapter surface configured to be received within the head cavity so that the proximal adapter surface is oriented toward the proximal convex articulating surface and the distal adapter surface is oriented away from the proximal convex articulating surface, the distal adapter surface having a diameter that is larger than a diameter of the proximal adapter surface, an adapter cavity extending from the distal adapter surface toward the proximal adapter surface;
a humeral base component including a circular proximal base surface configured to confront the distal surface of the humeral head component in an assembled condition of the humeral head implant system, and a distal extension for implantation into a humerus of a patient, a base cavity extending from the proximal base surface in a direction toward the distal extension; and
a fastener extending from a proximal-most end to a distal-most end, the proximal-most end of the fastener having a width that is greater than a width of the distal-most end of the fastener, wherein in an assembled condition of the humeral head implant system, the proximal-most end of the fastener is received within adapter cavity and the distal-most end of the fastener is received within the base cavity to couple the adapter to the humeral base component.
2 . The humeral head implant system of claim 1 , wherein the head cavity is positioned radially inward of the rim.
3 . The humeral head implant system of claim 1 , wherein the proximal convex articulating surface is ellipsoidal.
4 . The humeral head implant system of claim 1 , wherein the head cavity in the humeral head component defines a central head cavity axis, and the head component defines a head axis extending through a center of the proximal convex articulating surface, the head axis spaced from and parallel to the head cavity axis.
5 . The humeral head implant system of claim 1 , wherein in the assembled condition of the humeral head implant system, the fastener is positioned through a center of the circular proximal base surface of the humeral base component.
6 . The humeral head implant system of claim 5 , wherein the adapter cavity has a central axis which is offset from a center of the proximal adapter surface.
7 . The humeral head implant system of claim 1 , wherein the adapter is configured to couple to humeral base component, via the fastener, at a plurality of different orientations relative to the humeral base component, each of the plurality of different orientations resulting in a correspondingly different position of the humeral head component relative to the humeral base component.
8 . The humeral head implant system of claim 1 , wherein the distal extension of the humeral base component has a tri-fin configuration including three fins extending radially outwardly from the distal extension.
9 . The humeral head implant system of claim 8 , wherein a first fin and a second fin of the three fins each extend radially outward from the distal extension a first distance, and a third fin of the three fins extends radially outward from the distal extension a second distance, the second distance being less than the first distance.