Agreement of imageless navigation-derived pelvic tilt measurements with radiographic and CT-based measurements in direct anterior total hip arthroplasty: A prospective single-center study.
prospective_cohort · Level II
Where this comes from
- Record sourced from PubMed, PMID 42415944.
- Also identified by DOI 10.1002/jeo2.70842 and PMC identifier 13340135.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Pelvic tilt (PT) is a major determinant of functional acetabular orientation, affecting implant stability and impingement risk. Although imageless navigation systems are increasingly used to guide intraoperative cup orientation, their validity in measuring supine PT remains unclear. This study evaluated the validity of an imageless navigation system relative to preoperative computed tomography (CT)-based planning and intraoperative radiographic measurements during direct anterior approach (DAA) total hip arthroplasty (THA). This prospective observational study included consecutive patients undergoing primary DAA-THA between August 2023 and June 2024 at a single ambulatory surgery center. Sagittal PT was measured intraoperatively using imageless navigation and compared with CT-based preoperative planning and cross-table intraoperative lateral X-ray measurements. Agreement among the navigation system, lateral X-ray and preoperative planning was assessed. Demographic characteristics, morphometric variables and suprapubic fat thickness (SPFT) were collected to assess their associations with measurement error. Fifty-one patients were included (64.7% female; mean age, 59.6 ± 10.8 years). Bland-Altman analysis showed greater bias for X-ray_Navigation (3.7 ± 3.6°; limits of agreement [LoA]= -3.3° to 10.7°) and Navigation_CT (3.6 ± 4.9°; LoA = -6.0° to 13.3°) than for CT_X-ray (-0.1 ± 3.6°; LoA = -7.2° to 7.0°). Mean absolute error (MAE) was 4.1 ± 3.1°, 2.9 ± 2.2° and 4.8 ± 3.8° for X-ray_Navigation, CT_X-ray, Navigation-CT, respectively. SPFT independently predicted increased MAE in both the X-ray_Navigation and Navigation_CT comparisons. Receiver operating characteristic analysis identified SPFT cutoffs of 48.9 and 47.1 mm for predicting ≥5° discrepancies in the X-ray-Navigation and Navigation-CT comparisons, respectively. The imageless navigation device demonstrated moderate agreement with CT-based and intraoperative radiographic measurements and may provide clinically useful intraoperative estimation of supine PT during DAA-THA. However, SPFT was independently associated with larger measurement discrepancies. Level III.