Patent · US Expired

Semi-restraining knee prosthesis

US4215439A · kind A · utility

98Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 16, 1978
Grant dateAug 5, 1980
Priority date
Expiry dateOct 16, 1998

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61F2/3886
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A surface replacement knee joint prosthesis is provided which restrains axial and lateral rotation of the knee joint when the leg is fully extended, and superior-inferior dislocation at all times. The prosthesis has femoral and tibial members articulated by spaced spheroidal load-sharing condylar surfaces with substantially matching radii of curvature. The femoral member defines a tapering channel positioned between the spaced condylar surfaces. A stem having a truncated head projects superiorly from the tibial member and progressively engages the tapering channel during extension, for restraining the rotation and dislocation of the knee joint when the leg is fully extended. When the leg is in flexion, the clearance between the stem and the diverging arms which define the channel allows axial and lateral rotation as in a natural knee joint.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.