Implant component assembly

1 . An implant component assembly for a joint replacement, the assembly comprising:

an implant component, the implant component including an interface part configured for attaching to another implant component and an assembly channel,

an assembly screw for securing the other implant component to the implant component, the assembly screw having a longitudinal axis, a screw head, and a screw shank and being insertable into the assembly channel,

a screw retention unit configured for keeping the assembly screw within the assembly channel and allowing rotation of the assembly screw about the longitudinal axis,

another interface part for attaching a joint member, wherein the another interface part comprises a tapered recess and a concave interface surface, wherein the concave interface surface comprises an array of indexing holes,

a joint assembly channel that extends from the tapered recess along a longitudinal axis of the tapered recess to a side of the implant component opposite to the side of the implant component where the tapered recess is located, wherein the screw head is between the another interface part and the another implant component,

wherein the screw retention unit includes a screw seat for supporting the screw head, the screw seat comprising a through hole for accommodating the screw shank,

wherein the screw shank of the assembly screw comprises a threaded portion and an unthreaded portion, the unthreaded portion being located between the threaded portion and the screw head, and

wherein the screw seat engages a portion of the screw shank having a reduced diameter in comparison to the threaded portion of the screw shank.

2 . The implant component assembly of claim 1 , wherein the assembly channel comprises an accommodation portion and the screw seat is insertable into the accommodation portion.

3 . The implant component assembly of claim 2 , wherein the screw seat is fixed within the accommodation portion by a form fit, friction fit, or welding.

4 . The implant component assembly of claim 1 , wherein the screw retention unit comprises a screw stop, the screw stop being formed as a step of the assembly channel.

5 . The implant component assembly of claim 1 , wherein a diameter of the assembly channel is smaller than a diameter of the screw head.

6 . The implant component assembly of claim 1 , wherein the screw retention unit comprises a screw stop, wherein a distance in the longitudinal direction between the screw seat and the screw stop is larger than the screw head in the longitudinal direction.

7 . The implant component assembly of claim 1 , wherein the interface part of the implant component comprises a tapered interface surface for mounting the other implant component, the tapered interface surface defining a recess.

8 . The implant component assembly of claim 1 , wherein the implant component further comprises at least one suture hole and/or at least one suture groove for securing soft tissue to the implant component.

9 . The implant component assembly of claim 1 , wherein the implant component further comprises a handling tool engagement recess for engaging a handling tool for handling the implant component during a surgical procedure.

10 . The implant component assembly of claim 1 , wherein the assembly screw comprises a tool interface recess formed for an engagement of a fastening tool in a rotational direction about the longitudinal axis of the assembly screw.

11 . The implant component assembly of claim 1 , wherein the array of indexing holes are arranged in a circle, wherein a center of the circle is located along the longitudinal axis of the tapered recess.

12 . A method for pre-assembling an implant component assembly of a joint replacement, the method comprising the steps:

providing an implant component assembly for a joint replacement according to claim 1 , wherein the assembly channel is formed as a through hole and extends from a proximal side of the implant component to the interface part;

providing the screw seat;

providing the assembly screw having the longitudinal axis, the screw head, and the screw shank;

inserting the screw shank of the assembly screw into the through hole of the screw seat to form an assembled screw seat;

inserting the assembled screw seat with the screw head first into an accommodation portion of the assembly channel from the side of the interface part; and

fixing the screw seat within the accommodation portion of the assembly channel.

13 . The method for pre-assembling of claim 12 , further comprising the steps:

providing another implant component, the other implant component comprising an interface part corresponding to the interface part of the implant component and a threaded hole for engagement with the assembly screw;

connecting the implant components via their interface parts; and

securing the implant components to each other via tightening the assembly screw.