Results of the anatomic cementless prosthesis with different types of hydroxyapatite coating.

This study evaluates the clinical and radiographic results and the bone-implant osteointegration obtained with the Anatomic (Zimmer, Warsaw, Ind) cementless total hip prosthesis using three different types of surface coating. Two hundred twenty-seven patients underwent total hip arthroplasty using the Anatomic prosthesis. Patients were divided into groups based on the type of surface coating: in group A (69 patients), prostheses were uncoated; in group B (90 patients), the metaphyseal region of the prostheses was coated with calcicoat (a mixture of hydroxyapatite and tricalcium phosphate) (Zimmer); and in group C (68 patients), the fiber mesh and proximal stem of the prostheses were coated with calcicoat. Prostheses coated with calcicoat yielded better clinical and radiographic results than uncoated prostheses, especially in regard to thigh pain. No significant difference was observed between groups B and C. These results obtained with the Anatomic prosthesis are promising and encourage the use of implants coated with calcicoat.