AMS HA CUP and PerFix HA STEM (Kyocera)

Hydroxyapatite (Ca10(PO4)6(OH)2: HA) is a ceramic material with a composition similar to that of inorganic bone which was developed by Aoki et al., in the 1970s [1]. HA is characterized by its direct chemical bonding to the bone and was initially studied as filler for bone defects. The early research on HA for joint prosthesis was conducted in the 1980s as a surface coating material on the base metal, owing to its low mechanical strength. In the late 1980s, clinical application of HA-coated THA (HA-THA) was initiated. However, many of the early HA-THAs relied solely on the HA coating for bone anchorage of the implant, resulting in poor clinical outcomes, especially on the cup side [5–8].