Patterns of osseointegration and remodeling in femoral revision with bone loss using modular, tapered, fluted, titanium stems

Radiographic signs of osseointegration with the use of fluted, tapered, modular, titanium stems in revision hip arthroplasty with bone loss have not been previously categorized. Serial radiographs of 64 consecutive hips with mean follow-up of 6.2 years were retrospectively reviewed. Bone loss was classified as per Paprosky classification, osseointegration was assessed according to a modified system of Engh et al, and Harris Hip Score was used to document pain and function. Seventy-four percent of the hips had type 3 or 4 bone loss. All stems were radiographically osseointegrated. Early minor subsidence was seen in 6.2% of the hips; definite bony regeneration, 73% of the hips; and stress shielding, 26% of the hips. These osseointegration patterns were different from those described for extensively porous-coated cobalt-chromium stems and had a bearing on the evaluation of fixation of these stems.