Surgical treatment of non-displaced subcapital hip fracture: Femoral Neck System vs. cannulated screws. Comparative study.

Objective: The objective of this study is to compare the outcomes of using the Femoral Neck System (FNS) (DePuy Synthes®) versus the use of cannulated screws (CS) in the surgical treatment of non-displaced subcapital hip fractures.

Materials and methods: A retrospective cohort study was conducted on non-displaced subcapital hip fractures treated with CS or FNS between 2020 and 2023, with a minimum follow-up of one year. A total of 28 patients were included, 14 treated with CS and 14 with FNS. Demographic, radiological, clinical, and functional variables were analyzed.

Results: In the CS group, 64% were male, with a mean age of 66.5 years (SD 14.9) and an average follow-up of 22 months (range, 12-36 months). In the FNS group, 57% were male, with a median age of 60.8 years (SD 13.78) and an average follow-up of 16 months (range, 12-24 months). Regarding functional outcomes, no significant differences were found between FNS and CS in the Harris scale: 94.21±11.55 for FNS and 96.50±6.9 for CS (p=0.618). The total postoperative complications (FNS/CS) were 7.1% versus 43%, and implant failure with conversion to total hip replacement was 0% versus 43%, both significantly higher in the CS group (p=0.047; p=0.016, respectively). The FNS also presented a lower rate of avascular necrosis (0% versus 11.1%, p=0.391) and nonunion (0% versus 20%, p=0.163), although these differences did not reach statistical significance.

Conclusions: Although both treatment methods, cannulated screws and the FNS, showed similar short-term functional outcomes in the management of undisplaced subcapital femoral fractures, the FNS demonstrated a significantly lower rate of complications and reoperations. These results suggest that the FNS could be considered a safer and more effective option compared to cannulated screws.