To analyze the effect of orthopedic robot-assisted femoral neck system (FNS) fixation in the treatment of unstable femoral neck fractures.

A total of 81 patients with unstable femoral neck fractures admitted to department of trauma orthopedics of No.215 Hospital of Shaanxi Nuclear Industry were selected from June 2021 to June 2024. According to the surgical methods, the enrolled patients were divided into robot group (orthopedic robot + FNS fixation, n=46) and control group (artificial surgery + FNS fixation, n=35). Inculusion criteria: unilateral unstable femoral neck fractures, age 18 to 75 years, normal hip before the fracture, patient accepted robot assisted or traditional FNS fixation with complete information. Exclusion criteria: hip fracture history, pathologic fractures or multi-fractures, follow-up duration less than six months, vital organ dysfunction, severe osteoporosis, etc. The surgical indicators, numerical rating scale (NRS), Harris hip score (HHS), pain factors and postoperative complications were compared between the two groups by t test, analysis of variance, and chi square test.

The intraoperative blood loss volume and intraoperative fluoroscopy frequency in the robot group were 25 (22, 31) ml and (14±3) times, which were less than 31 (26, 38) ml and (15±3) times in the control group (Z=4.631, t=2.455, both P<0.05). The success rate of one-time nail placement was 100.0% in the robot group which was higher than 80.0% in the control group (Fisher’s exact test P=0.002). There were no statistical differences in surgical time and hospitalization time between groups (Z=1.639, t=1.693, both P>0.05). Repeated measures analysis of variance revealed that the NRS score in the two groups showed a decreasing trend (time-point F=227.30, P<0.001; between groups F=8.83, interaction F=3.75, both P<0.05), and the NRS scores were 5.7±1.1 and 4.1±1.0 in the robot group at one day and three days after surgery, which were lower than 6.5±1.3 and 4.8±1.1 in the control group (t=2.715, 2.878, both P<0.05). HHS score in both groups showed an increasing trend (time-point F=483.43, P<0.001, between-group F=5.31, P=0.022, interaction F=1.49, P>0.05), and HHS score in the robot group were 82±9 at three months after surgery, which was higher than 76±7 in the control group (t=3.311, P<0.05), while there was no statistical significance in HHS score at six months after surgery between groups (t=1.548, P>0.05). Prostaglandin E₂ (PGE₂) and neuropeptide Y (NPY) in the two groups increased first and then decreased, and no statistical differences were exhibited in PGE₂ and NPY between groups at one day after surgery (t=1.664, 1.717, both P>0.05). PGE₂ and NPY in the robot group at three days after surgery were lower than those in the control group (t=2.155, 2.586, both P<0.05). There was no statistical difference in total incidence rate of postoperative complications between the robot group (10.9%) and the control group (17.1%) (χ²=0.667, P>0.05).

Orthopedic robot-assisted FNS fixation for unstable femoral neck fractures can effectively relieve the postoperative pain, and promote the short-term hip joint recovery, and it has small trauma to patients and is conducive to postoperative rehabilitation.