Value of musculoskeletal ultrasound in shock wave therapy of long tubular bone fracture nonunions

Abstract

Objective To assess the value of musculoskeletal ultrasound in extracorporeal shock wave therapy (ESWT) of long tubular bone fracture nonunions. Methods A total of 41 patients with 45 fracture nonunions were enrolled. Fracture gap distance, soft tissue incarceration, foreign body in the gap, and blood flow near the fracture gap were assessed by ultrasound before ESWT. Fracture gap, large blood vessels, nerves, and fixations on the body surface were marked. After ESWT, ultrasonic examination was performed every two months for detecting the distance of nonunion gap, echogenicity of the gap, and blood flow near the fracture gap. Anteroposterior and lateral projection X-ray films were used to assess the healing of the fractures. Results One patient with tibia fracture accepted surgical operation for incarceration of the extensor digitorum longus. No neurovascular complication was found in the patients treated with musculoskeletal ultrasound-guided ESWT. Significantly increased blood flow near the fracture gap was found in five patients, and 24 patients were diagnosed with fracture healing according to clinical and X-ray examinations. Ultrasonography showed fracture line healing in six cases, fractured gap less than 2 mm in 28 cases, and hyperechoic fractured gap in 22 cases. Using fracture gap less than 2.1 mm with hyperechogenicity or fracture line disappearance as the ultrasonic criteria of diagnosing fracture healing, the accuracy, sensitivity, and specificity were 95.5%, 91.7%, and 100.0%, respectively. Conclusion Musculoskeletal ultrasound may be used as an effective method for preoperative evaluation of indications of ESWT, intraoperative localization, and postoperative evaluation of therapeutic effects. Key words: Musculoskeletal ultrasound; Fracture nonunion; Shock wave therapy