The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 06, 1992
Filed:
Oct. 04, 1991
Matthew Lyons, West Brookfield, MA (US);
Exactech, Inc., Gainesville, FL (US);
Abstract
A femoral stem prosthesis including a stem tapering from a proximal end to a distal end, and having a primary zone of taper and a secondary zone of taper. The secondary zone of taper, located at the distal end of the stem, has a larger angle of taper than that of the primary zone of taper, but substantially less than the taper in prior art stems. In the secondary zone of taper, the stem gradually tapers away from the femoral bone to avoid a sudden change in stress level in the bone at the distal stem tip, thus avoiding the incidence of thigh pain. The stem of the inventive prosthesis preferably includes longitudinal channels to increase its flexibility and preferably has a trapezoidal cross-sectional geometry to resist rotational forces and to provide multi-plane stability within the femur, thereby providing effective stress transfer to the femur.