Anterior pelvic plane registration accuracy and cup position measurement using ultrasound- and pointer-based navigation in primary total hip arthroplasty

Article type: Research Article

Authors: Kiefer, Hartmuth^{a; 1} | Löchel, Jannis^{b; 1; *} | Sambo, Keosun^a | Leder, Björn^a | Wassilew, Georgi I.^c

Affiliations: [a] Department of Orthopaedic and Trauma Surgery, Lukas-Hospital Bünde, Germany | [b] Center for Musculoskeletal Surgery, Orthopaedic Department, Charité – Universitätsmedizin Berlin, Berlin, Germany | [c] Department for Orthopaedic Surgery, University of Greifswald, Greifswald, Germany

Correspondence: [*] Corresponding author: Jannis Löchel, %****␣thc-28-thc191888_temp.tex␣Line␣125␣**** Center for Musculoskeletal Surgery, Orthopaedic Department, Charité – Universitätsmedizin Berlin, Charitéplatz 1 D – 10117 Berlin, Germany. Tel.: +49 3834 86 7061; E-mail: jannis.loechel@uni-greifswald.de.

Note: [1] Co-first/equal authorship.

Abstract: BACKGROUND: Incorrect cup positioning in primary total hip arthroplasty is known as a risk factor for early implant failure. The use of navigation systems leads to more accurate cup positioning. OBJECTIVE: The aim of this study was to compare the registration accuracy of the anterior pelvic plane and the measurement accuracy of the definite cup position for a pointer computer-assisted orthopaedic navigation system (P-CAOS) and an ultrasound-based navigation tool (US-CAOS) in an intra-individual study design. METHODS: Anterior pelvic plane registration was performed in 44 patients receiving a primary total hip arthroplasty with P-CAOS and US-CAOS. The cup implantation was performed using US-CAOS. Intraoperatively, the cup position was assessed using P-CAOS and US-CAOS. The postoperative cup position was determined via CT scan. Inclination and anteversion errors were calculated using intraoperative values and CT data. All operations were performed by a single, high-volume surgeon using a minimally invasive anterolateral approach. RESULTS: The mean inclination error was 0.9∘ in the US-CAOS group and -1.1∘ in the P-CAOS group. This was not statistically significant. The mean anteversion error was significantly reduced (p< 0.001) in the US-CAOS group (1.4∘) compared to the P-CAOS group (-8.0∘). Significantly more cups (23 of 44; 52%) in the P-CAOS group were outliers regarding to the defined anteversion error range of 15∘± 10∘. Outliers in the US-CAOS group amounted to two (of 44; 5%) (p< 0.001). The number of outliers regarding the inclination error range of 40∘± 10∘, did not differ significantly between the P-CAOS (2; 5%) and US-CAOS (1; 2%) group. CONCLUSION: We were able to show a systematic anterior pelvic plane registration error in this intraindividual study design. US-CAOS based APP landmark registration showed to be significantly more precise compared to P-CAOS registration. The anteversion error of the cup using US-CAOS showed to be significantly reduced compared to the P-CAOS method.

Keywords: Primary total hip arthroplasty, ultrasound-based navigation, pointer-based navigation, anterior pelvic plane, registration error, anteversion error, inclination error, orthopaedic navigation system, cup positioning

DOI: 10.3233/THC-191888

Journal: Technology and Health Care, vol. 28, no. 3, pp. 315-323, 2020