title: The John Charnley Award paper. Efficacy of using a bone graft substitute to enhance biological fixation of a porous metal femoral component.
abstract: The efficacy of using hydroxyapatite/tricalcium phosphate (HAP/TCP) particles to enhance the biological fixation of a canine cementless femoral component with a noninterference fit was evaluated with a custom-designed collarless, wedge-shaped femoral component with titanium fiber metal pads along the anteroposterior surfaces of the stem. A polyethylene acetabular component was cemented into the pelvis. Three groups of dogs were employed: group I (n = 7) had a femoral component with an interference fit; group II (n = 6) had a component with a noninterference fit with uniform voids along the anteroposterior stem surfaces; and group III (n = 6) had a component with a noninterference fit including uniform voids filled with HAP/TCP particles. All dogs were harvested after 12 weeks of unrestricted weight bearing. Cross-section specimens from three different levels from each bone-component composite were evaluated histologically to determine the type and extent of tissue ingrowth and the percentage of peripheral bone or HAP/TCP particles adjacent to the fiber metal pad surfaces. Three other cross-section specimens, adjacent to the histological section levels of the same composites, were assessed for shear strength at the fiber metal-tissue interface and for biochemical composition of the ingrown tissue.
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001861:Bone Regeneration; D001842:Bone and Bones / Q000032:analysis; D002118:Calcium / Q000032:analysis; D002130:Calcium Phosphates; D004285:Dogs; D005269:Femur / Q000000981:diagnostic imaging; D006025:Glycosaminoglycans / Q000032:analysis; D006615:Hip / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006882:Hydroxyapatites; D008670:Metals; D011474:Prosthesis Design; D011509:Proteoglycans / Q000032:analysis; D011859:Radiography
chemical_list: D002130:Calcium Phosphates; D006025:Glycosaminoglycans; D006882:Hydroxyapatites; D008670:Metals; D011509:Proteoglycans; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous; D002118:Calcium