title: A Madreporic-surfaced femoral component in a canine total hip arthroplasty model: bone remodelling response at 6 and 24 months.
abstract: OBJECTIVE
  To evaluate the bone-remodelling response at 6 and 24 months after total hip arthroplasty around a two-thirds Madreporic-surfaced femoral component in a canine model.
  
  
  METHODS
  A research study in dogs. Statistical analysis was by multivariate analysis of variance.
  
  
  METHODS
  A musculoskeletal research laboratory in a university teaching hospital.
  
  
  METHODS
  Ten mature mixed-breed dogs.
  
  
  METHODS
  Unilateral implantation of total hip arthroplasty in the right femur with a Madreporic-surfaced prosthesis. Studies were conducted at 6 months in five dogs and at 24 months in five dogs. In each case, the nonoperated femur was the study control.
  
  
  METHODS
  Fluorescence microscopy analysis on comparable sections at four levels of the femora, percent porosity computed by image analysis, cortical atrophy.
  
  
  RESULTS
  Cancellous hypertrophy was most prominent at the junction of the beaded and smooth portions of the femoral stem. At 6 months the cortex demonstrated atrophy predominant in the anteromedial quadrant. Active bone turnover was present within the interstices of the prosthesis at 6 and 24 months. No significant cortical bone loss occurred between 6 and 24 months. Stress transfer to the bone-prosthesis interface and endosteal cortical "cancellization" appear to be linked phenomena.
mesh_terms: D000818:Animals; D001178:Arthroplasty; D016723:Bone Remodeling / Q000502:physiology*; D002858:Chromium Alloys; D004285:Dogs; D006622:Hip Prosthesis; D015999:Multivariate Analysis; D011474:Prosthesis Design; D013499:Surface Properties; D013997:Time Factors
chemical_list: D002858:Chromium Alloys