Devices and methods for bone fixation
Devices and methods for bone fixation including a bone fixation system including a bone plate or intervertebral spacer including a plurality of apertures dimensioned to receive bone fasteners and at least one polymeric element capable of transitioning from a solid state to a flowable state. The polymeric element transitions to a flowable state as a result of exposure to ultrasonic vibration. The polymeric element is placed on the bone plate or intervertebral spacer adjacent a fastener in an aperture and acts to prevent rotational and/or translational movement of the fastener relative to the bone plate or intervertebral spacer.
1 . A bone fixation system, comprising:
a plate, configured for placement adjacent to a patient's bone, including a plurality of apertures each dimensioned to receive a fastener there through and a polymeric element adjacent at least two apertures, wherein the plate includes a recess in a surface of the plate that is adjacent to and in communication with the at least two apertures;
one or more fasteners configured to extend through the at least two apertures to secure the plate to the bone;
a sonotrode configured to change a physical state of the polymeric element;
wherein upon introducing the sonotrode to the polymeric element, material of the polymeric element flows into a space adjacent the one or more fasteners in the at least two apertures such that the material of the polymeric element is in contact with both the plate and the one or more fasteners; and
wherein upon removing the sonotrode from the polymeric element, the material of the polymeric element is configured to harden to a solid state, thereby preventing the one or more fasteners from moving relative to the plate.
2 . The bone fixation system of claim 1 , wherein the recess is in communication with the two apertures along at least a portion of a perimeter of each of the two apertures.
3 . The bone fixation system of claim 2 , wherein the recess is in communication with the two apertures along an entire perimeter of each of the two apertures.
4 . The bone fixation system of claim 1 , wherein the polymeric element comprises a thermoplastic material.
5 . The bone fixation system of claim 1 , wherein the polymeric element prevents the one or more fasteners from translating in a direction opposite of a direction of insertion.
6 . The bone fixation system of claim 1 , wherein the polymeric element prevent the one or more fasteners from rotating.
7 . The bone fixation system of claim 1 , wherein each of the one or more fasteners comprises a shank portion and a head portion having a circumferential surface with a recess.
8 . The bone fixation system of claim 7 , wherein the material of the polymeric element is configured to flow into the recess on the circumferential surface of the head of each of the one or more fasteners.
9 . The bone fixation system of claim 1 , wherein the plate is configured for spinal fixation.
10 . The bone fixation system of claim 1 , wherein the plate is configured for long bone fixation.
11 . The bone fixation system of claim 1 , wherein the recess in the surface of the plate is adjacent to and in communication with each of the plurality of apertures.
12 . The bone fixation system of claim 11 , wherein the material of the polymeric element is configured to flow in each of the plurality of apertures.