Methods, materials and apparatus for treating bone and other tissue
View Patent ↗A method of treating a vertebra, comprising: (a) accessing an interior of a vertebra; and (b) introducing a sufficient amount of artificial biocompatible material which does not set to a hardened condition in storage, into said bone, with sufficient force to move apart fractured portions of said bone.
1. A surgical set comprising:
at least one tool adapted to deliver a material into a vertebra, the tool including a pressure delivery mechanism which comprises;
a) a body which contains a piston and has an input port;
b) a delivery tube which is connected to the body through which the material is delivered to a patient's vertebra; and
c) a hydraulic actuator which is connected to the body at the input port for delivering hydraulic fluid under pressure to the body to push against the piston to cause material in the delivery tube to be delivered to the patient's vertebra, the hydraulic actuator being a pump which comprises a piston and a cylinder having matching threads so that the hydraulic fluid can be pumped by rotating the piston; and
at least 1 cc of artificial biocompatible prepared material contained within the delivery tube, in which the pressure delivery mechanism is capable of delivering the material at a pressure of above 10.13 MPa (100 atmospheres).
2. A set according to claim 1 , wherein said set comprises a disposable hydraulic actuator.
3. A set according to claim 1 , wherein said set comprises a replaceable magazine for storing said material.
4. The surgical set of claim 1 , wherein the material has a Young modulus of less than 120% of healthy vertebral trabecular bone.
5. The surgical set of claim 1 , wherein the material has a Young modulus of less than 600 megapascal.
6. The surgical set of claim 1 , wherein the material has a Young modulus of less than 300 megapascal.
7. The surgical set of claim 1 , wherein the material is an acrylic bone cement that sets to a hardened condition.
8. The surgical set of claim 7 , wherein the acrylic bone cement comprises a mixture of PMMA beads and MMA monomers.
9. The surgical set of claim 8 , wherein the PMMA beads include beads having a size of 10 to 200 microns.
10. The surgical set of claim 9 , wherein the PMMA beads are provided in a range of sizes.
11. The surgical set of claim 10 , wherein the bead sizes and ratios of materials in the acrylic bone cement mixture are selected to result in a viscosity working window before setting of at least 5 minutes.
12. The surgical set of claim 1 , wherein the hydraulic actuator is coupled to the body by a flexible conduit.
13. The surgical set of claim 1 , wherein the hydraulic actuator provides a hydraulic advantage.
14. The surgical set of claim 13 , wherein the hydraulic actuator provides a hydraulic gain of at least 1:3.
15. The surgical set of claim 13 , wherein the tool comprises a pressure relief valve.
16. The surgical set of claim 1 , further comprising a barrel for holding the prepared material prior to injecting the material through the delivery tube.
17. The surgical set of claim 1 , wherein the body further comprises a pusher that extends into the delivery tube and is acted on by the piston in the body to cause the material located in the delivery tube to be displaced.
18. The surgical set of claim 1 , in which the viscosity of the material is from 600 Pa·s to 1800 Pa·s for a period of at least 5 minutes after mixing.