Risk of Intraoperative Periprosthetic Femoral Fracture According to Cementless Femoral Stem Geometry: A Cohort Study...

Area of Science:

• Orthopedic Surgery
• Biomaterials Engineering
• Medical Device Design

Background:

• Intraoperative periprosthetic femoral fracture is a significant complication of total hip arthroplasty (THA), potentially compromising implant stability.
• Cementless femoral stems, used for press-fit stability, may have a higher fracture incidence compared to cemented stems.
• The Radaelli classification system standardizes cementless femoral stem comparison by geometry, length, and modularity.

Purpose of the Study:

• To evaluate the association between femoral stem geometry, using the Radaelli classification, and the risk of intraoperative periprosthetic fracture in primary THA.
• To identify specific cementless femoral stem designs that may increase fracture risk.

Main Methods:

• A retrospective cohort study of 1,384 patients undergoing primary THA with uncemented femoral components.
• Femoral stem geometry was classified according to the Radaelli system.
• Logistic regression analysis was used to assess the association between stem geometry and intraoperative fracture occurrence.

Main Results:

• An overall intraoperative femoral periprosthetic fracture incidence of 3.6% was observed.
• Flat wedge stems had the highest proportion of fractures (34%), followed by short fit-and-fill stems (20%).
• No statistically significant association was found between most stem geometries and fracture risk, except for C2 fit-and-fill stems in a small sample.

Conclusions:

• Most femoral stem geometries, per the Radaelli classification, are not significantly associated with increased intraoperative fracture risk in primary THA.
• While flat wedge stems showed a higher fracture proportion, this was not statistically significant.
• Further research with larger sample sizes is needed to confirm findings, especially for specific geometries like C2 fit-and-fill stems.