An accelerometer-based navigation system provides acetabular cup orientation accuracy comparable to that of computed tomography-based navigation during total hip arthroplasty in the supine position

Tomonori Tetsunaga, Kazuki Yamada, Tomoko Tetsunaga, Tomoaki Sanki, Yoshi Kawamura, Toshifumi Ozaki

Research output: Contribution to journalArticle


Background: Inadequate acetabular component orientation is associated with postoperative impingement, dislocation, and accelerated polyethylene wear. Computed tomography (CT)-based navigation systems provide accuracy for total hip arthroplasty (THA) but are not available in all facilities. Accelerometer-based navigation systems are inexpensive, but their accuracy remains undetermined. This study compares the accuracy of cup orientation in THA using CT-based and accelerometer-based navigation systems. Methods: This retrospective study included 35 consecutive patients (11 males, 24 females; mean age, 65 years) who underwent primary cementless THA via an anterolateral approach in the supine position. Both CT-based and accelerometer-based navigation systems were used simultaneously. The accuracy of cup orientation was compared between the two systems using postoperative CT. Results: The accuracy of cup inclination was 2.7° ± 2.0° in the CT-based group and 3.3° ± 2.4° in the accelerometer-based group. The accuracy of cup anteversion was 2.8° ± 2.6° in the CT-based group and 3.4° ± 2.2° in the accelerometer-based group. No significant difference was observed in cup inclination (p = 0.29) or cup anteversion (p = 0.34) between CT-based and accelerometer-based navigation. Conclusions: The accuracy of cup positioning did not differ significantly between CT-based and accelerometer-based navigation systems.

Original languageEnglish
Article number147
JournalJournal of Orthopaedic Surgery and Research
Issue number1
Publication statusPublished - Apr 15 2020



  • Hip
  • Navigation system
  • Retrospective study
  • Total hip replacement

ASJC Scopus subject areas

  • Surgery
  • Orthopedics and Sports Medicine

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