Claims
- 1. A process of preparing an orthopedic device, comprising the steps of:
a) providing a polyethylene workpiece; and b) positioning an irradiation source adjacent to the workpiece so that the workpiece may be exposed to irradiation from the irradiation source; and c) interrupting the irradiation source so that only portions of the workpiece are exposed to irradiation.
- 2. The method of claim 1, further comprising the step of translating the workpiece.
- 3. The method of claim 1, further comprising the step of arranging a perforated mask between the irradiation source and the workpiece.
- 4. The method of claims 1, further comprising the step of arranging a wire mesh between the irradiation source and the workpiece.
- 5. The method of claim 3, wherein the perforated mask is curved.
- 6. The method of claim 4, wherein the wire mesh surrounding the workpiece is curved.
- 7. The method of claim 1, further comprising a rotatably mounted chopper wheel between the irradiation source and the workpiece.
- 8. The method of claim 1, further comprising the step of pulsing the irradiation source.
- 9. The method of claim 1, wherein the irradiation step is controlled to deliver a dose of irradiation between 2.5 and 100 Mrads.
- 10. The method of claim 1, wherein the irradiation step is controlled to deliver a dose of irradiation between 5 and 15 Mrads.
- 11. The method of claim 1, further comprising the step of pre-forming the workpiece into a form suitable for implantation prior to the irradiation step.
- 12. The method of claim 11, wherein said pre-forming step comprises injection molding said workpiece into forms suitable for implantation prior to the irradiation step.
- 13. The method of claim 12, wherein said injection molding step is performed with a blend of UHMWPE and HDPE to form said workpiece.
- 14. The method of claim 12, wherein said injection molding step is performed with a blend of UHMWPE and HDPE to form said workpiece, said blend having a ratio of about 30:70 UHMWPE to HDPE.
- 15. The method of claim 1, further comprising the step of shaping said workpiece into the forms selected from the group consisting of acetabular cups, knees, ankles, shoulders, tibial and femoral joints, finger and thumb members, vertebra, elbows, foot, toe and wrist members.
- 16. The method of claim 1, wherein the composition of the polyethylene workpiece is selected from the group comprising high molecular weight polyethylene, ultra high molecular weight polyethylene, high density polyethylene, ultra high density polyethylene, cross-linked polyethylene and non-cross-linked polyethylene.
- 17. The method of claim 1, wherein the polyethylene is UHMWPE.
- 18. The method of claim 17, wherein the UHMWPE has a molecular weight between about 1,000,000 to 10,000,000.
- 19. The method of claim 18, wherein the UHMWPE has a molecular weight between about 2,000,000 to 6,000,000.
CROSS REFERENCE
[0001] This is a divisional application of U.S. patent application Ser. No. 09/553,503, filed Apr. 20, 2000, entitled SELECTIVELY CROSS-LINKED POLYETHYLENE ORTHOPEDIC DEVICES, which claims the benefit of Provisional Application 60/130,322, filed Apr. 21, 1999. The contents of these applications are hereby incorporated by reference in their entirety.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60130322 |
Apr 1999 |
US |
Divisions (1)
|
Number |
Date |
Country |
Parent |
09553503 |
Apr 2000 |
US |
Child |
10095240 |
Mar 2002 |
US |