Does Intraoperative Fluoroscopy Improve Limb-Length Discrepancy and Acetabular Component Positioning During Direct...

One potential benefit of the direct anterior approach (DAA) for total hip arthroplasty is the ability to use intraoperative fluoroscopy for acetabular cup positioning and limb-length evaluation. Previous studies comparing the use of fluoroscopy with an anterior approach to a posterior approach have reported conflicting results. To our knowledge, no prior study has compared acetabular cup position and limb-length discrepancy (LLD) using a DAA with and without fluoroscopy.

We retrospectively reviewed the charts of 298 patients who underwent direct anterior total hip arthroplasty with or without intraoperative fluoroscopy. All procedures were performed by 2 surgeons who use DAA as their primary approach. Preoperative and 6-week postoperative low anteroposterior pelvis and cross-table lateral radiographs were reviewed by 3 independent surgeons. Acetabular cup inclination, anteversion, and LLD were measured and compared.

Thirty-three patients were excluded for inadequate imaging, leaving 125 patients in the fluoroscopy group and 140 patients in the nonfluoroscopy group. Mean inclination, anteversion, and LLD were 39.4° (95% confidence interval [CI], 38.5°-40.2°), 30.2° (95% CI, 29.2°-31.2°), and 1.1 mm (95% CI, 0.1 mm-2.2 mm) for the fluoroscopy group and 39.9° (95% CI, 39.3°-40.5°), 31.1° (95% CI, 30.0°-32.2°), and 0.8 mm (95% CI, -0.1 mm to 1.6 mm) for the nonfluoroscopy group. There was no significant difference in acetabular inclination (P = .35), anteversion (P = .22), or postoperative LLD (P = .64) between groups.

This study found no clinically or statistically significant difference in acetabular inclination, anteversion, or LLD between the fluoroscopy and nonfluoroscopy groups. Both surgeons achieved a similar mean acetabular cup position and an equivalent mean LLD.