title: Low accuracy of stem implantation in THR using the CASPAR-system: anteversion measurements in 10 hips.
abstract: We studied 10 patients by means of pre- and postoperative CT who underwent computer-assisted total hip replacement using the CASPAR-system (OrthoMaquet GmbH, Rastatt, Germany). The anteversion angles of the stem and translational deviations measured after surgery were compared to the preoperatively planned ones as a quality control. We found an average difference of 7.8 degrees (SD 6.3 degrees; 95% CI 3.3 degrees-12.3 degrees) in the angles and an average difference of 1.8 (SD 1.7; 95% CI 0.6-3.0) mm and 1.2 (SD 1.4: 95% CI 0.25-2.2), respectively, in the medial and lateral deviation. In conclusion, we could not confirm the same accuracy of implant position as that claimed by the manufacturer.
authors.affiliation: Department of Orthopedics, University of Rostock, Germany. farhad.mazoochian@med.uni-rostock.de
authors.forename: Farhad
authors.initials: F
authors.lastname: Mazoochian
authors.forename: Christoph
authors.initials: C
authors.lastname: Pellengahr
authors.forename: Armin
authors.initials: A
authors.lastname: Huber
authors.forename: Jörn
authors.initials: J
authors.lastname: Kircher
authors.forename: Hans Jürgen
authors.initials: HJ
authors.lastname: Refior
authors.forename: Volkmar
authors.initials: V
authors.lastname: Jansson
mesh_terms: D000368:Aged; D000886:Anthropometry; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed