title: The long-term clinical relevance of calcar atrophy caused by stress shielding in total hip arthroplasty: a 10-year, prospective, randomized study.
abstract: Eighty osteoarthritic female patients were randomly allocated to 4 equal groups; the Zwey-Muller, the Corail, the Optifix, or Autophor 900S cementless total hip arthroplasties (THAs) were implanted; and bone density changes, at different sites, were prospectively studied. In zone 7, the greatest reduction of bone density values was observed at 2 years (group A: 24%, group B: 8%, group C: 14.8%, and group D: 18.5%). In all groups, a similar pattern of slow but progressive recovery of bone mineral density changes after the third year was observed, approaching baseline values at 10 years, during which all patients showed satisfactory clinical results. We suggest that the clinical and theoretical relevance of the stress-shielding phenomenon in THA has been overestimated in the literature.
authors.affiliation: Orthopaedic Department, University of Thessaly, Larisa, Hellenic Republic, Greece.
authors.forename: Theofilos
authors.initials: T
authors.lastname: Karachalios
authors.forename: Christos
authors.initials: C
authors.lastname: Tsatsaronis
authors.forename: George
authors.initials: G
authors.lastname: Efraimis
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Papadelis
authors.forename: George
authors.initials: G
authors.lastname: Lyritis
authors.forename: George
authors.initials: G
authors.lastname: Diakoumopoulos
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D015519:Bone Density; D005260:Female; D005269:Femur / Q000503:physiopathology*; D006622:Hip Prosthesis; D006801:Humans; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery*; D010014:Osteolysis / Q000209:etiology*; D011446:Prospective Studies; D011474:Prosthesis Design; D016896:Treatment Outcome