A Comparative Analysis of Femoral Neck System and Three Cannulated Screws Fixation in the Treatment of Femoral Neck Fractures: A Six-Month Follow-Up

Abstract

Objective: To investigate the efficacies of Femoral Neck System (FNS) and the three cannulated screws fixation (3CS) as therapeutic options for femoral neck fractures.

Method: This was a retrospective study involving 69 patients (26 males and 43 females; mean age of 54.9 years (range, 28-66 years)) subjected to either FNS or 3CS for femoral neck fracture therapy. These patients were treated in our hospital from October 2019 to May 2020. Patient follow up was done at 1, 2, 3 and 6 months. During the short-term (6 months) follow-up period, surgical procedures for the two groups and incidences of complications were analyzed. Perioperative parameters were recorded and analyzed. Postoperative hip joint functions were measured and compared using the Harris score. The assessed perioperative parameters included surgical time, hemoglobin loss, fluoroscopy duration, hospitalization length and hospitalization cost. The main complications at last follow-up (6 months) included varus tilting, femoral neck shortness, and implant removal.

Results: Differences in the number of patients, age, Garden type of fracture and time from injury to surgery between the two groups were not significant (P > 0.05). With regards to perioperative parameters, compared to 3CS, FNS treatment performed better in surgical time (60.00 ± 12.44 vs 76.81 ± 13.10 min, P = 0.000), blood loss (13.67 ± 8.02 vs 16.58 ± 4.16 g/L, P = 0.059) and fluoroscopy time (39.73 ± 9.57 vs 58.14 ± 9.15 s, P = 0.000). Differences in hospitalization length and cost between the groups were not significant (P > 0.05). During the whole follow-up period, all patients did not exhibit dysfunction, pulmonary embolism or even death as a result of long-term immobilization of affected limbs. Surgical incisions for all patients healed well without infections. During the 6-month follow-up period, the FNS group exhibited a higher Harris score (84.61 ± 3.42 vs 78.67 ± 3.72, p = 0.000). In addition, treatment-associated complications (FNS vs 3CS) included femoral neck varus tilt (3.03% vs 11.11%), femoral neck shortness (6.06% vs 13.89%), and implant removal (0% vs. 13.89%). Implant removal rate for the FNS group was significantly less than that of the 3CS group (P = 0.026). Differences in incidences of femoral neck varus tilt (P = 0.196) and femoral neck shortness (P = 0.282) between the two groups were not significant. However, the difference in number was significant (FNS group was less).

Conclusion: FNS treatment is associated with a smaller surgical trauma, stronger stability, and reductions in post-operative complication incidences, therefore, it is a potential therapeutic option for femoral neck fractures.

Keywords: Cannulated screws fixation; Femoral neck fractures; Femoral neck shortness; Femoral neck system; Implant removal; Varus tilting.