Hip joint prosthesis

Claim 1

A hip joint prosthesis comprising a femoral component having a joint head and an elongated shank formed of an elastic titanium-base metal alloy having an elastic modulus comparable to that of human bone, the joint head adapted to cooperate with the natural acetabulum or a prosthetic acetabulum, the shank having a proximal end adjacent the joint head and a distal end, the shank having substantially parallel lateral and medial sides such that the width of the shank is approximately constant along substantially the entire length of the shank in the lateral-medial plane, the shank having anterior and posterior sides slightly inclined towards each other in the distal direction such that the shank is slightly tapered distally in the anterior-posterior plane, and the shank being straight and having an approximately uniform cross-section over a major portion of its length starting from said distal end, and with a multiplicity of discrete, generally cylindrically-shaped protuberances spaced from one another being provided on portions of at least the anterior, posterior and medial sides of the shank, the height of said protuberances being smaller than their diameter and the spacing between adjacent protuberances being smaller than their diameter, and said protuberances being rounded at their free ends to avoid sharp edges.