2023, Vol. 27 ›› Issue (27): 4318-4323

OrthoPilot navigation system assisted total hip arthroplasty improves the accuracy and safety of acetabular cup placement

Ren Yi, Lu Ming, Qin Kunpeng, Zhang Hui, Gao Weilu, Li Yetian, Wang Jun, Yin Li, Yin Zongsheng   

Abstract: BACKGROUND: As a classic surgical method for the treatment of femoral head necrosis and femoral neck fracture, total hip arthroplasty has some problems, such as poor placement of prosthesis, postoperative dislocation and so on. OrthoPilot navigation assisted total hip arthroplasty can theoretically improve the accuracy and safety of prosthesis placement. At present, there are few studies on its application in total hip arthroplasty in China.  
OBJECTIVE: To explore the feasibility and short-term clinical effect of OrthoPilot navigation assisted total hip arthroplasty.
METHODS: A retrospective analysis was performed in 23 patients who received OrthoPilot navigation assisted total hip arthroplasty in the Department of Joint surgery of the First Affiliated Hospital of Anhui Medical University from June 2019 to April 2022. A total of 23 patients with freehand total hip arthroplasty were matched at 1:1 according to sex, age, body mass index and preoperative Harris score. The anteversion and inclination angles during and after operation were measured and counted. The operation time, total blood loss, postoperative drainage, average hemoglobin loss and postoperative Harris scores were calculated.  
RESULTS AND CONCLUSION: (1) The operation time in the navigation group was (152.4±39.9) minutes and in the non-navigation group was (115.3±35.4) minutes, with statistically significant (P=0.02). (2) In terms of angle measurement, the anteversion angle of acetabular cup was (42.3±3.5)° during operation and (42.6±5.5)° after operation, with no significant difference (P=0.574) in the navigation group. The inclination angle of acetabular cup was (18.5±3.4)° during operation and (19.3±3.9)° after operation, with no significant difference (P=0.567) in the navigation group. (3) According to “Lewinnek safe zone”, 22 hips were in the safety zone and 1 hip outside the safety zone after operation in the navigation group, while 17 hips were in the safety zone and 6 hips outside the safety zone after operation in the non-navigation group, showing a significant difference (χ2=4.212, P=0.04). (4) In terms of surgical treatment, there was no significant difference in total blood loss, postoperative drainage, average hemoglobin loss, Harris score, and the incidence of postoperative lower extremity deep venous thrombosis between the two groups. (5) The average follow-up was 3 months after operation, and there were no patients with early infection or dislocation in the two groups. (6) These results verify that OrthoPilot navigation assisted total hip arthroplasty can improve the accuracy and safety of acetabular cup placement, and its short-term clinical effect is not significantly different from that of freehand total hip arthroplasty.

Key words: OrthoPilot navigation, total hip arthroplasty, inclination angle, anteversion angle, safety zone