Bone remodeling in experimental total hip arthroplasty.

Experimental studies of cementless porous-coated total hip arthroplasty indicate that the most important design variable for femoral remodeling is stem stiffness. In the long-term (2 years) in the canine model, other variables including the presence, type and placement of the porous coating did not significantly affect the pattern of bone remodeling when tested with metallic stems. The basic pattern of bone remodeling was characterized by proximal cortical atrophy, and distal cortical and medullary bone hypertrophy. The use of low stiffness stems altered this pattern, leading to reduced proximal bone loss and no distal cortical hypertrophy.