title: Primary metal-on-metal total hip arthroplasty with large-diameter femoral heads: a clinical trial of 59 hips.
abstract: Large-diameter femoral heads with nearly anatomical sizes became available for metal-on-metal total hip arthroplasty after recent advances in metal-on-metal technology. We retrospectively studied the clinical and radiological results in 59 hips of 54 patients (32 women and 22 men, mean age 54.4 years) who underwent cementless metal-on-metal total hip arthroplasty with large-diameter heads. Patients were followed for a mean of 48.6 months. Range of motion improved significantly after surgery (p = 0.001). Harris hip scores improved from 38.5 points to 903 points at latest follow-up. We found no gender-related differences in Harris hip scores, whereas there was a correlation between age and Harris hip scores (p < 0.001), with excellent results being observed predominantly in younger patients. Mean acetabular inclination of the acetabular cup was 42.2 degrees (range: 37-51 degrees). Radiologically, a 1 mm thick radiolucency was detected in three acetabula, which were asymptomatic. One acetabulum was revised because of displacement. Three patients reported squeaking within their hips, which however disappeared in a short time. We did not observe any dislocation, deep infection or loosening. Grade 1 heterotopic ossification was detected in one hip. Although the inherent stability and the functional results of large anatomical heads are encouraging, longer follow-up data and larger series are essential to evaluate the real advantages of this type of prosthesis over conventional femoral heads.
authors.affiliation: Ataturk Training and Research Hospital, Department of Orthopaedics and Traumatology, Ankara, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Cicek
authors.forename: Kasim
authors.initials: K
authors.lastname: Kilicarslan
authors.forename: Nadir
authors.initials: N
authors.lastname: Yalcin
authors.forename: Erhan
authors.initials: E
authors.lastname: Arslan
authors.forename: Yunus
authors.initials: Y
authors.lastname: Dogramaci
authors.forename: Hasan
authors.initials: H
authors.lastname: Yildirim
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D005260:Female; D006621:Hip Joint / Q000503:physiopathology; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000453:epidemiology; D015207:Osteoarthritis, Hip / Q000601:surgery; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D012189:Retrospective Studies
chemical_list: D008670:Metals