Abstract: A system for fixing a prosthetic component to an anchor implanted in the bone of a patient. The prosthetic component includes a fixing channel and an installation channel. The fixing channel opens to an engagement collar configured to engage with a bone anchor. The installation channel opens from an outer surface of the prosthetic and communicates with the fixing channel. The installation channel permits placement of a fastener therethrough into the fixing channel to secure the prosthetic to the bone anchor. The axes of the fixing channel and the installation channel intersect at a point which lies within the radius of a fastener seat which is configured to engage a head of the fastener when the fastener is placed into the fixing channel.