Dear Helen, goog results for  orthopedics may be obtain when we introduce hydroxyapatite into polymer matrix. See, for example, our paper   Panin, S.V. Nano- and Micro-Structured UHMWPE Composites Filled With Hydroxyapatite Irradiated by Nitrogen Ion Beams for Bio-Medical Applications / S.V. Panin, L.A. Kornienko, M.V. Chaikina, V.P. Sergeev, L.R. Ivanova, S.V. Shil’ko // Russian Physics Journal. – 2014. – Vol. 56, № 10. – P. 1137–1143. 

All  the best, Serge

Thank you sir.I got some information

There are many materials, which can be used with hydroxyapatite. They comprise polymers, ceramics and even some metals. However, all of them must be, at least, bioinert but, preferably, they should be biocompatible and/or biodegradable. Therefore, just search in Google or scientific databases for biocompatible polymers (there are plenty of them), bioceramics (titania, zirconia, alumina, carbon, etc.) and biocompatible (Ti, noble metals, stainless steel) or biodegradable (Mg and its alloys) metals.

Depending on the type of treatment you are focusing, there are many combinations that can be used but depending on you objectives. HA can be combined with different materials for bone repair of load bearing or non load bearing area, for diagnostic purpose, for cancer treatment, for bone disease therapy and etc. Please specify your objective in use of HA

Sergey V. Dorozhkin -Thank you sir.But tell me little bit about bioinert  and importance of that.

Bioinert means that they do not interact with tissues. Normally, they are chemically stable compounds such as Al2O3, ZrO2, TiO2, stainless steel, Ti, Ta, noble metals, carbon. Therefore, implants from such materials will stay in the body forever without changes.

Dear Helen, following this discussion and first answer of Sergey V. Dorozhkin it may be noticed that in some cases the biocompatible composites are advisable when biodegradable  matrix materials interacting with tissues can be served as  temporary binder for GA and other fillers. First of all, organic compounds, polymers such as polycaprolactam are biocompatible in terms of degradation mechanism mentioned above. Until their full disapperance...   

Yes thank you for your explanation.

You may want to check a related discussion at this forum: https://www.researchgate.net/post/Is_there_any_bio-activity_explanation_of_hydroxyapatite_towards_bone_growth_or_with_surrounding_tissues