Method for drilling a bore in bone using a compaction drill

• US 5,443,468 A
• Filed: 02/04/1994
• Issued: 08/22/1995
• Est. Priority Date: 02/04/1994
• Status: Expired due to Term

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Lanny L. Johnson
• Inventors: Johnson, Lanny L.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): Tucker, Guy V.
• Application Number:
  US08/191,610
• Time in Patent Office: 564 Days
• Field of Search: 606/80, 606/79, 606/84, 606/85, 606/96, 606/99, 606/102, 606/105, 606/170, 606/180, 623/13, 408/1 R, 408/207, 408/209, 408/226, 408/229, 408/230, 433/165, 433/166, 33/511, 33/512
• US Class Current: 606/80
• CPC Class Codes: A61B 17/1615 Drill bits, i.e. rotating tools extending from a handpiece to contact the worked material
• CPC Class Codes: A61B 17/885 Tools for expanding or compacting bones or discs or cavities therein A61B17/8805, A61B17/7097 take precedence

Abstract

A drill bit is provided that is constructed and arranged to form a bore in a bone by cutting and moving bone fragments to a wall of the bore. The drill bit includes an elongated shaft having a distal portion and a proximal portion. The proximal portion has a constant diameter. A cutting tip is defined at the free end of the distal portion. A segment of the distal portion has transverse cross-sectional area less than that of the proximal portion. The distal portion segment also includes a surface to facilitate movement of the bone fragments towards the proximal portion of the shaft. When the drill bit enters the bone so as to form the bore and is moved an amount such that the distal portion is disclosed completely within the bore, a space is defined between the wall of the bore and a periphery of the segment of the distal portion which receives the bone fragments. Further insertion of the drill bit into the bone causes the bone fragments to move along the surface of the distal portion segment to the outer cylindrical surface of the proximal portion which compacts the bone fragments against the wall of the bore.

Claims

1. A method of forming a bore in bone comprising the steps of:

initiating a bore in said bone utilizing a drill bit of the type comprising an elongated shaft having a cylindrical proximal portion of substantially constant diameter and cross-sectional area and a distal portion, said distal portion including a cutting element at a free end thereof and a segment having varying cross-sectional area less than that of said proximal portion, said segment joining the cutting element to the proximal portion and increasing in cross-sectional area between said element and the proximal portion;

advancing said drill bit further into the bone to lengthen the bore and move fragments of bone, created by advancing the drill bit, to said segment of varying cross-sectional area thereby retaining said bone fragments between a wall of the bore and said segment;

further advancing said drill bit into the bone whereby additional creation of bone fragments causes retained fragments to be moved against the wall of the bore and forced between the wall and said proximal portion whereby the bone fragments are compacted against and along a portion of the wall to increase the density of said portion of the wall; and

removing said drill bit from said bore.

2. A method of forming a bore in bone according to claim 1, further comprising the step of:

additionally compacting and enlarging the bore following removal of the drill bit by inserting into the bore a sizing instrument having a larger diameter than that of said drill bit.