The Clinical Value of Extracorporeal Shock Wave Therapy Evaluated by Contrast-Enhanced Ultrasound for Noninfectious Nonunion

Objectives: The aim of this study was to investigate the clinical value of Contrast-enhanced ultrasound (CEUS) in evaluating Extracorporeal shock wave therapy (ESWT) for noninfectious nonunion. Methods: Thirty-eight patients with long bone nonunion fractures whose were treated in our hospital from October 2016 to October 2019 were included (20 males and 18 females). The patients received ESWT once a week for 12 consecutive weeks. CEUS was performed before and after the first ESWT session. According to the ratio of the perfusion area to the callus area, neovascular blood flow observed in CEUS was divided into 4 grades: grade 0 = 0%, grade 1 = 0–30%, grade 2 = 30–70% and grade 3 = 70–100%. The peak values of microbubbles perfusion in the callus area were recorded before and after ESWT. Each patient was followed up for 12 months to record the healing time. Nonunion over 12 months was considered a nonhealing fracture. To compare the ultrasonic data before and after ESWT, paired T test was used and the correlation between the ultrasonic data and the nonunion healing time, the pearson analysis was used. Results: Of the 38 patients, 35 patients achieved nonunion healing. The healing time ranged from 5 months to 12 months. Among the 38 patients, 24 patients had a microvascular health score of 0 points and 14 patients had a score of 1 point before treatment. After therapy, the neovascular health score was 0, 1, 2 and 3 in 5, 10, 15 and 8 patients, respectively. There was a statistically significant difference before and after treatment (P < 0.05). The peak value of microbubbles perfusion in the fracture site after ESWT was significantly higher than that before ESWT (P < 0.05). The greater of difference, the shorter of healing time. Conclusion: Under the supervision of CEUS, the changes in microvascular perfusion of noninfectious nonunion patients before and after ESWT effectively reflected the therapeutic effect. CEUS could predict the ESWT on bone nonunion at an early stage. Level of evidence: Level III.