Real-Time Fluoroscopic Navigation Improves Acetabular Component Positioning During Direct Anterior Approach Total Hip Arthroplasty.

We investigated whether a novel, real-time fluoroscopybased navigation system optimized component positioning and leg length in fluoroscopically aided direct anterior approach total hip arthroplasty (DAA-THA). We retrospectively reviewed 75 fluoroscopically assisted DAA-THA performed by a single surgeon: 37 procedures used the software intraoperatively to overlay anteversion, inclination, and leg length information over the existing fluoroscopic radiograph with the aim of enhancing component positioning. The control group consisted of 38 procedures from the single surgeon's patient pool who had undergone non-navigated fluoroscopic assisted DAA-THA 1 month prior to the system's trial. Our results demonstrate that the navigation group measurements were significantly closer to the target numbers with less variation. The mean difference from target value were as follows: for anteversion (control: -4.68°, navigated: -01.0°), inclination (control: -1.87°, navigated: 0.8°), and leg length discrepancy (control: -2.59°, navigated: -0.98°). In addition, surgical time was shorter in the navigation group (75.7 vs. 74 minutes; p = 0.001). The real-time feedback and calculations provided by the navigation software provided a reproducible precision for component positioning and leg length measurement during DAA-THA.