Joseph R Dvorak

US Patent:

20040260208, Dec 23, 2004

Filed:

Jun 20, 2003

Appl. No.:

10/601003

Inventors:

Robert Laprade - Chanhassen MN, US
Fred Wentorf - Roseville MN, US
David Strothman - Minnetonka MN, US
Joseph Dvorak - Minneapolis MN, US

International Classification:

A61B005/11

US Classification:

600/595000

Abstract:

A device for measuring a varus rotation angle in a knee comprises a femoral reference member configured to be positioned medially of the knee, a first arm hingedly engaged to the femoral reference member, and a first potentiometer to output an angular relationship between the femoral reference member and the first arm. The device also includes a second arm hingedly engaged to the first arm, and a second potentiometer to output an angular relationship between the first and second arms, wherein the varus rotation angle is determinable from the outputs of the first and second potentiometers. Furthermore, a joint-space opening of the knee joint may be determined using the outputs of the first and second potentiometers.