B ﹒股骨侧Engh改良的Gruen分区(引自:Engh CA,Bobyn JD,Glassman AH ﹒ Porous‐Coated hip replacement ﹒ Thefactors governing bonein gronth,stress shielding,and clinical results ﹒ J Bone Joint Surg(Br),1987,69:45‐. ......