Resorbable compressing screw and method

• US 4,776,329 A
• Filed: 09/20/1985
• Issued: 10/11/1988
• Est. Priority Date: 09/20/1985
• Status: Expired due to Fees

• Current Assignee: Smith & Nephew Richards Incorporated (Smith & Nephew PLC)
• Original Assignee: Richards Medical Company
• Inventors: Treharne, Richard
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Isabella, David J.
• Application Number:
  US06/778,232
• Time in Patent Office: 1,117 Days
• Field of Search: 128/92 B, 128/92 BA, 128/92 BB, 128/92 C, 128/92 CA, 128/92 D, 128/92 G, 128/92 YV, 128/92 Y, 128/92 YR, 128/92 YF, 623/16
• US Class Current: 606/65
• CPC Class Codes: A61B 17/746 the longitudinal elements coupled to a plate opposite the femoral head
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: Y10S 606/908 Bioabsorbable material

Abstract

A method for repairing a bone fracture with a compression screw assembly is provided. First and second non-resorbable compression members are positioned so that the head portion of the compression screw can protrude from the surface of the second non-resorbable compression member after further compression is effected by the normal healing process. At least the head portion of the screw is formed of a material that resorbs upon contact with body fluids.

Claims

1. A method for repairing a bone fracture with a compressing screw having a head portion and first and second non-resorbable compression members positioned so that the head portion of the screw can protrude from the surface of the second non-resorbable compression member after further compression is effected by the normal healing process, comprising the steps of:

(a) connecting the first non-resorbable compression member to a first bone section on one side of a fracture;

(b) connecting the second non-resorbable compression member to a second bone section on the other side of the fracture, the first and second members cooperating in such a way that the compressing screw can be used to compress the fracture by pulling the holding the first and second members together; and

(c) compressing the fracture by utilizing the compressing screw with the head portion spaced from the bone fracture area and that bears against the first non-resorbable compression member, at least the head portion being formed of a material that resorbs on contact with body fluids.

2. The method of claim 1, wherein the head is formed with an opening of the middle thereof to expose a greater portion of the head to body fluids.

3. The method of claim 1, wherein the head is formed with notches to expose a greater portion of the head to body fluids.

4. The method of claim 2, wherein the resorbable material is formed of poly (DL-lactide) having a weight molecular weight of 40,000-160,000.

5. A method for repairing bone fractures with a compressing screw having a head portion, and first and second non-resorbable compression members positioned so that the head portion of the screw can protrude from the surface of the second non-resorbable compression member after further compression is effected by the normal healing process, comprising the steps of:

(a) connecting the first compression member to a first bone section on one side of a fracture;

(b) connecting the second compression member to a second bone section on the other side of the fracture, the first and second members cooperating in such a way that a compressing screw can be used to compress the fracture by pulling the first and second members together,

(c) compressing the fracture by inserting and tightening a non-resorbable compressing screw, and

(d) replacing said non-resorbable compressing screw with a compressing screw with at least head portion formed of a material that resorbs on contact with body fluids, after the non-resorbable screw has been used to compress the fracture.

6. The method of claim 5, wherein the compressing screw is formed entirely of resorbable material.

7. The method of claim 6, wherein the head is formed of a material that resorbs faster than the remainder of the screw.

8. The method of claim 5, wherein the head is formed with an opening on the middle thereof to expose a greater portion of the head to body fluids.

9. The method of claim 5, wherein the head is formed with notches to expose a greater portion of the head to body fluids.

10. The method of claim 6, wherein the resorbable material is formed of poly(DL-lactide) having a weight molecular weight of 40,000-160,000.

11. A method for repairing bone fractures with a compressing screw having a head portion and first and second non-resorbable compression members positioned so that the head portion of the screw can protrude from the surface of the second non-resorbable compression member after further compression is effected by the normal healing process, comprising the steps of:

(a) connecting the first compression member to a first bone section on one side of a fracture;

(b) connecting the second compression member to a second bone section on the other side of the fracture, the first and second members cooperating in such a way that the compressing screw can be used to compress the fracture by pulling and holding the first and second members together, and

(c) compressing the fracture by utilizing a compressing screw formed entirely of resorbable material with a head portion that resorbs faster than the remainder of the screw.