Multi-axial connection system
View Patent ↗A system and method for a multi-axial connection of an apparatus to bone. The system may include a fastener inserted into a body and a head of the fastener held within a chamber of the body through a combination of a retention ring, a pressure cap, a rod, and a compression element. The compression element applies force to the rod which, in turn, pushed on the pressure cap. The force on the pressure cap urges it against the head of the fastener and pushed it against the retention ring. The force on the retention ring causes it to expand to the walls of the chamber. Once the ring can no longer expand within the chamber, the head of the fastener is wedged between the retention ring and the pressure cap.
1. A fixation system, comprising:
a body having a first end and a second end;
a body rod receiving channel disposed within the body and defined by a first wall and a second wall of the body;
a first and a second removal extensions that are coupled to the first and second walls of the body at a break region;
a fastener head receiving chamber disposed adjacent the second end of the body, wherein the fastener head receiving chamber is defined by the first wall and the second wall of the body and wherein the first wall and the second wall of the body are tapered from the first end towards the second end of the body, and wherein the body rod receiving channel and the fastener head receiving chamber are configured to communicate with one another;
a pin mounting channel positioned in the body having a first diameter that is larger than a second diameter;
a pin fixably attached to the body via the pin mounting channel, wherein the pin includes
a pin head that is larger than a pin shaft, the pin head having a pin head diameter configured to not extend beyond the first diameter of the pin mounting channel;
a pressure cap slidably engaged with the body, wherein the pressure cap includes pin receiving slots that extend through an entire width of a wall of the pressure cap, and wherein the pin receiving slots are elongated so that the pressure cap slidably moves between the body's first and second ends; and
a compression element configured to cooperate with the body and urge a rod, when the rod is disposed within the body rod receiving channel, into contact with at least part of the pressure cap.
2. The fixation system of claim 1 , further comprising a cannulated fastener having a head at a first end, wherein the head of the fastener includes a drive element.
3. The fixation system of claim 1 , wherein the pressure cap is configured to press the head of the fastener towards the tapered end of the fastener head receiving chamber.
4. The fixation system of claim 1 , further comprising a retention device disposed within the fastener head receiving chamber and configured to retain the fastener head within the fastener head receiving chamber.
5. The fixation system of claim 4 , wherein the retention device is a split ring.
6. The fixation system of claim 1 , wherein the first and second removable extensions are configured to break off at the respective break region.
7. The fixation system of claim 1 , wherein the compression element includes threads that cooperate with complimentary internal threads of the body.
8. The fixation system of claim 7 , wherein compression element includes threads that cooperate with complimentary internal threads on the first and second removable extensions.
9. The fixation system of claim 1 , wherein the first and second removable extensions are configured to break off at the respective break region after the compression element moves the rod below the break region.
10. The fixation system of claim 1 , wherein the body comprises an aperture in one of the walls of the body rod receiving channel.
11. The fixation system of claim 1 , wherein the compression element is a set screw.
12. A fixation system, comprising:
a body having a first end and a second end;
a body rod receiving channel disposed within the body and defined by a first wall and a second wall of the body;
a first and a second removal extensions that are coupled to the first and second walls of the body at a break region, the first and second removal extensions include threads on an inner surface;
a fastener head receiving chamber disposed adjacent the second end of the body, wherein the fastener head receiving chamber is defined by the first wall and the second wall of the body and wherein the first wall and the second wall of the body are tapered from the first end towards the second end of the body, and wherein the body rod receiving channel and the fastener head receiving chamber are configured to communicate with one another;
a pin mounting channel positioned in the body having a first diameter that is larger than a second diameter;
a pressure cap slidably engaged with the body, wherein the pressure cap includes pin receiving slots that extend through an entire width of a wall of the pressure cap, and wherein the pin receiving slots are elongated so that the pressure cap slidably moves between the body's first and second ends;
a pin fixably attached to the body via the pin mounting channel, wherein the pin extends into the pin receiving slots of the pressure cap; and
a compression element configured to cooperate with the body and urges a rod, when the rod is disposed within the body rod receiving channel, into contact with at least part of the pressure cap.
13. The fixation system of claim 12 , wherein the pin includes a pin head that is larger than a pin shaft, the pin head having a pin head diameter configured to not extend beyond the first diameter of the pin mounting channel.
14. The fixation system of claim 12 , further comprising a cannulated fastener having a head at a first end, wherein the head of the fastener includes a drive element.
15. The fixation system of claim 12 , further comprising a retention device disposed within the fastener head receiving chamber and configured to retain the fastener head within the fastener head receiving chamber.