Intramedullary implant with locking and compression devices
View Patent ↗An intramedullary fixation device includes an intramedullary implant having a longitudinal bore along a longitudinal axis, a two-component compression device and a two-component locking device, both devices preassembled in the longitudinal bore. The intramedullary implant includes an elongated slot and first and second apertures transversely crossing the longitudinal axis. The compression device is movable along the longitudinal axis and defines an end opening aligned with the elongated slot of the intramedullary implant. The locking device includes first and second openings aligned along the first and second apertures of the intramedullary implant.
1. An intramedullary fixation device comprising:
an intramedullary implant having a longitudinal bore along a longitudinal axis, the longitudinal bore having a first internally threaded portion and a second internally threaded portion, the intramedullary implant including an elongated slot and first and second apertures transversely crossing the longitudinal axis;
a two-component compression device preassembled in the longitudinal bore of the intramedullary implant, a first component of the compression device defining a first plurality of threads that engage the first internally threaded portion, the compression device movable along the longitudinal axis, a second component of the compression device defining an end opening aligned with the elongated slot of the intramedullary implant; and
a two-component locking device preassembled in the longitudinal bore of the intramedullary implant, a first component of the locking device defining a second plurality of threads that engage the second internally threaded portion, a second component of the locking device including first and second openings aligned along the first and second apertures of the intramedullary implant.
2. The fixation device of claim 1 , wherein the second component of the compression device is coupled to the first component of the compression device.
3. The fixation device of claim 2 , wherein the first component of the compression device includes a resilient portion and a flange received in an internal groove of the second component of the compression device.
4. The fixation device of claim 3 , wherein the second component of the locking device is coupled to the first component of the locking device.
5. The fixation device of claim 4 , wherein the first component of the locking device includes a resilient portion and a flange received in an internal groove of the second component of the locking device.
6. The fixation device of claim 5 , wherein the second component of the compression device has an outer periphery keyed to a first inner periphery of the longitudinal bore at a first location.
7. The fixation device of claim 6 , wherein the second component of the locking device has an outer periphery keyed to a second inner periphery of the longitudinal bore at a second location.
8. The fixation device of claim 7 , wherein the second inner periphery of the longitudinal bore in the second location is different than the first inner periphery of the longitudinal bore in the first location.
9. The fixation device of claim 8 , wherein the first inner periphery is smaller than the second inner periphery.
10. The fixation device of claim 1 , wherein the end opening of the compression device and the first and second openings of the locking device each include internal ridges for engaging corresponding threaded fixation fasteners.
11. An intramedullary fixation device comprising:
an intramedullary implant having a longitudinal bore along a longitudinal axis, the intramedullary implant including an elongated slot and first and second apertures transversely crossing the longitudinal axis;
a compression device preassembled in the longitudinal bore of the intramedullary implant, the compression device movable along the longitudinal axis, the compression device including a first component threadably coupled to the longitudinal bore of the intramedullary implant and a second component coupled to the first component, the second component having an end opening aligned with the elongated slot of the intramedullary implant; and
a locking device preassembled in the longitudinal bore of the intramedullary implant, the locking device including a first component threadably coupled to the longitudinal bore of the intramedullary implant and a second component coupled to the first component, the second component including first and second openings aligned along the first and second apertures of the intramedullary implant,
wherein the first component and the second component of the compression device are each separate from the first component and the second component of the locking device.
12. The fixation device of claim 11 , wherein the end opening of the compression device is defined between first and second end extensions of the second component of the compression device.
13. The fixation device of claim 11 , wherein one of the first and second openings of the locking device is defined between end extensions of the second component of the locking device.
14. The fixation device of claim 11 , wherein each one of the end opening of the compression device and the first and second openings of the locking devices includes internal ridges for engaging threaded fixation fasteners received through the corresponding openings.
15. The fixation device of claim 11 , wherein each one of the first components of the compression and locking devices includes a driver engagement formation.
16. The fixation device of claim 11 , wherein each one of the compression and locking devices is cannulated along the longitudinal axis of the intramedullary implant.
17. The fixation device of claim 11 , wherein the end opening of the compression device is substantially perpendicular to the longitudinal axis of the intramedullary implant and oriented in a lateral-medial direction.
18. The fixation device of claim 11 , wherein the first and second openings of the locking device are substantially perpendicular to one another, and wherein one opening is oriented in a lateral-medial direction and the other opening is oriented in a posterior-anterior direction.
19. An intramedullary fixation device comprising:
an intramedullary implant for ankle arthrodesis, the intramedullary implant having a longitudinal bore along a longitudinal axis, an elongated talar slot, a lateral-medial through-hole, and a posterior-anterior through-hole, the longitudinal bore defining a first internally threaded portion and a second internally threaded portion;
a two-component compression device preassembled in the longitudinal bore of the intramedullary implant, a first component of the compression device defining a first plurality of threads threadably engagable with the first internally threaded portion, a second component of the compression device defining an end opening corresponding to the elongated slot for receiving a talar fixation fastener transversely to the longitudinal axis of the intramedullary implant, the first component of the compression device movable relative to the longitudinal bore to move the talar fixation fastener along the elongated slot for tibio-talar compression; and
a two-component locking device preassembled in the longitudinal bore of the intramedullary implant, a first component of the locking device defining a second plurality of threads threadably engagable with the second internally threaded portion, the second component of the locking device defining a through-hole corresponding to the posterior-anterior through-hole of the intramedullary implant for receiving a first calcaneal fixation fastener, the locking device defining an end opening corresponding to the lateral-medial through-hole of the intramedullary implant for receiving a second calcaneal fixation fastener, the first component of the locking device movable relative to the longitudinal bore and the compression device to lock the first and second calcaneal fasteners in the intramedullary implant.
20. The fixation device of claim 19 , wherein each one of the end opening of the compression device, the through-hole of the locking device and the end opening of the locking device includes internal ridges for engaging the corresponding talar, first calcaneal and second calcaneal fixation fasteners.
21. The fixation device of claim 19 in combination with the talar fixation fastener and the first and second calcaneal fixation fasteners, wherein each of the fixation fasteners is substantially perpendicular to the longitudinal axis of the intramedullary implant, and wherein the talar and the second calcaneal fasteners are substantially parallel to one another and substantially perpendicular to the first calcaneal fastener.