Smartphone-based navigation system enables low-volume surgeons to perform accurate acetabular cup placement: A single-center retrospective study

Purpose

Using navigation systems during total hip arthroplasty (THA) has been reported to be useful for preventing acetabular cup malpositioning. However, only few studies have reported on the application of navigation systems to THA at low-volume hospitals owing to cost and usage complexity. Therefore, the aim of this study was to determine whether smartphone-based portable navigation using augmented reality technology would enable low-volume surgeons to perform acetabular cup placement more accurately than with the conventional manual technique.

Methods

We retrospectively compared acetabular cup placement between the navigation (n ​= ​28) and conventional (n ​= ​24) groups. The acetabular cup inclination and anteversion angles were measured using computed tomography (CT)-based planning software. Furthermore, the absolute difference between the postoperative and target angles was compared between the groups.

Results

The absolute difference between the postoperative and target angles of cup inclination was 2.6° ​± ​2.3° in the navigation group and 5.6° ​± ​5.2° in the conventional group (p ​< ​0.01). Additionally, the cup anteversion was 3.2° ​± ​3.0° in the navigation group and 9.4° ​± ​7.1° in the conventional group (p ​< ​0.01).

Conclusions

Using a smartphone-based portable navigation system could allow for appropriate cup placement even by low-volume surgeons.