Radiographic Evaluation of Proximal Femoral Nutrient Arteries After Total Hip Arthroplasty With a Short Femoral Stem.

BACKGROUND

The use of less invasive approaches and broach only press-fit femoral stems in total hip arthroplasty (THA) may increase the risk for periprosthetic fracture. Proximal femoral nutrient arteries (FNAs) can be mistaken for fractures after THA. Description of FNAs in relation to THA implants is important to better distinguish between FNAs and periprosthetic fractures. The purpose of this study was to evaluate the frequency, location, and morphology of FNAs visible on radiographs after primary THA with a broach-only stem design.

METHODS

A retrospective cohort study was performed. Patients ≥18 years who underwent primary THA with a cementless, broach-only stem, and had 6-week follow-up radiographs were included. Patient demographics were recorded. Anteroposterior and lateral radiographs at 6 weeks postoperatively were assessed for the presence of FNA; if present, measurements of vessel location and morphology were obtained. Descriptive statistics were reported. Univariate and multivariate analyses were performed to identify patient characteristics associated with the radiographic presence of perforating vessel.

RESULTS

A total of 378 hips were evaluated (332 patients). FNAs were identified radiographically in 46.3% (175 hips/378 hips). All FNAs were found to be unicortical, most observed in the posterior and lateral cortices. Gender, age, BMI, stem position, and surgical approach did not correlate with a presence of FNA on radiograph.

CONCLUSION

FNA was seen on postoperative radiographs in 46% of patients after THA with one broach-only stem design. The FNA was unicortical and present on preoperative radiographs. Surgeons should consider this when evaluating postoperative radiographs.