Apparatus for sizing a femoral component

United States Patent [19]

McNulty et al.

US005562675A [li] Patent Number: [45] Date of Patent:

II

5,562,675 Oct. 8,1996

[54] APPARATUS FOR SIZING A FEMORAL
COMPONENT

[75] Inventors: Donald E. McNulty, Warsaw; David
C. Kelman, Winona Lake, both of Ind.;
John R. Moreland, Pacific Palisades,
Calif.; John E. Hamm, Warsaw, Ind.

[73] Assignee: DePuy Inc., Warsaw, Ind.

[21] Appl. No.: 437,848
[22] Filed: May 9,1995

Related U.S. Application Data

[62] Division of Ser. No. 937,704, Sep. 1, 1992, Pat. No. 5,445, 642.

[51] Int. CI.6 A61B 17/56

[52] U.S. CI 606/96; 606/102; 606/88

[58] Field of Search 606/87, 88, 102,

606/86, 82, 80, 96, 79; 623/18, 20

[56] References Cited

U.S. PATENT DOCUMENTS

Hack et al., "Surgical Procedure—The Omnifit® STAT-IMTM Surgical Instruments", Osteonics Corp., 1991, pp. 1-26.

"Surgical Technique for the AGC® total Knee System", ACCU-LINETM Knee Instrumentation, Biomet, Inc. Brochure, 1990, pp. 1-18, Author unknown.

Yoshioka et al., "The Anatomy and Functional Axes of the Femur", Journal of Bone and Joint Surgery, vol. 69-A, No. 6, Jul. 1987, pp. 873-880.

"Surgical Procedure for the Whiteside Ortholoc® Modular Knee System", Dow Corning Wright Brochure, 1990, pp. 1-38, Author unknown.

Scott, et al., "RFC.® Modular Knee System with Specialist® Instruments", Surgical Technique, Johnson & Johnson Orthopaedics, date unknown, pp. 1-97.

Insall et al., "Insall/Burstein® II Constrained Condylar Modular Knee System", Surgical Technique using Zimmer® Intramedullary Instrumentation, The Hospital for Special Surgery, date unknown, pp. 1-32.

"Zimmer Intramedullary Knee Instrumentation for the Miller/Gallante Total Knee System", Zimmer, Inc. brochure, 1986.

Primary Examiner—Michael Powell Buiz

Assistant Examiner—Guy V. Tucker

Attorney, Agent, or Firm—Barnes & Thornburg

A sizing assembly for determining the optimum size of a femoral component of a knee prosthesis is placed against the resected distal end of a femur. The assembly includes a body with a flat surface for contacting the resected surface of the femur and feet for engaging the femoral condyles. The assembly further includes a pivoted stylus that slides in the body and engages the anterior femoral cortex. Once the size of the femoral component is determined, a drill bushing corresponding to the femoral component is supported on the body. The drill bushing includes two apertures for guiding a drill to bore pilot holes in the resected femur.

5 Claims, 8 Drawing Sheets