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.

Fig. 1

(A) Manipulative reduction of the femoral neck before surgery, preoperative frontal and axial X‐rays of the hip joint showed that the femoral neck was well aligned; (B) The anti‐rotation guide needle was inserted, with the position of the guide needle avoiding the center of the femoral neck to leave space for the bolt; (C) The bolt guide pin was inserted and localized at the center of the femoral neck in the positive and lateral X‐ray of the hip joint; (D and E) Reamed along the guide pin (center distance ≤10 mm); (F) Knocked and inserted the bolt and outer steel plate along the guide needle; (G) The guide needle was pulled out; (H) The anti‐rotation screw and locking nail were inserted, and the fixed guide needle pulled out

Fig. 2

A 49‐year‐old female patient with left femoral neck fracture was treated with FNS. (A and B) Preoperative X‐ray and CT three‐dimensional reconstruction examination showed a left Garden type IV femoral neck fracture; (C and D) G‐arm machine fluoroscopy, manual traction and reduction of femoral neck fractures, exposing the lateral side of femur and femur for surgical marking; (E and F) A fixed guide pin was inserted to fix the femoral neck in order to prevent it from rotating and shifting during the operation; (G and H) Postoperative hip joint frontal and axial X‐rays revealed that the femoral neck was reduced and that the internal fixation position was good; (I and J) At 1 month of post‐operative follow‐up, hip joint frontal and axial X‐rays showed a good internal fixation position and callus existence; (K and L) At 6 months of post‐operative follow‐up, frontal and axial X‐rays of the hip joint showed that the fracture had healed and that the internal fixation position was good

Fig. 3

A 52‐year‐old female patient with left femoral neck fracture was treated with FNS. (A) Before surgery, frontal X‐ray imaging showed Garden IV femoral neck fracture; (B) Postoperative hip joint X‐ray imaging showed that internal fixation position of the fracture was good; (C, D and E) At 1, 2 and 3 months, post‐operative hip joint X‐rays showed good femoral neck fracture healing; (F and G) At 6 months, post‐operative hip joint frontal and axial X‐rays showed that the fracture had healed; (H) Surgical incision length was about 4–5 centimeters; (I and J) At 6 months after fracture healing, the patient was able to walk normally without squatting obstacles