Patent ID: 8206455

Claim:
A hip prosthesis having a medial side, a lateral side, an anterior side, and a posterior side, the hip prosthesis comprising: a neck; and a stem defining a longitudinal axis and having a proximal portion, a distal portion, and a transition portion extending between the proximal portion and the distal portion of the stem, the proximal portion of the stem including an anterior locking surface, a posterior locking surface, and a lateral surface, the anterior locking surface and the posterior locking surface of the proximal portion forming a first included angle of between six degrees and twenty degrees, the lateral surface of the proximal portion having an inflection point, the lateral surface angling toward the longitudinal axis of the stem in both a proximal direction from the inflection point and a distal direction from the inflection point, the lateral surface angling toward the longitudinal axis of the stem at a 2.5 degree angle in the distal direction from the inflection point, the transition portion of the stem having an anterior face and a posterior face that form a second included angle that is less than the first included angle.