The KAREY-HA® system for total hip arthroplasty has been designed to provide an optimal combination of strength and minimizing geometry setting offering a respectful anatomy in which it is integrated concept. Stem KAREY® -HA is intelligently designed: a) At its proximal or metaphyseal area, has a progressive trapezoidal geometry allows optimum adaptation of the stem as well as a translational anti-, anti-rotational mounting prosthetic that provides a perfect primary stability avoiding collapse. b) There is a progressive slots in the medial side to promote bone growth and join the anti-translational property (sinking) cited above. c) In the distal zone has a hypo-sized favors progressive stiffness decreased stem avoiding this the “stress-shielding” mode. Stem KAREY HA® is a non-cemented prosthesis.