Ultrasonographic bridging callus as an early predictor of tibial fracture healing.

Abstract

This study assessed whether ultrasonographic (U/S) detection of bridging callus can serve as an early sign of tibial fracture healing. By comparing U/S with serial radiographs, the goal was to identify the best predictors of fracture union. Previous studies indicate that early radiographic bridging callus may signal eventual healing, and U/S could detect this sooner than X-rays. Thus, U/S may provide earlier predictions of bone union or impaired healing. A prospective evaluation was conducted on a consecutive cohort of patients with tibial fractures managed by intramedullary nailing. Patients were followed until complete bone healing or determination of nonunion at twelve months. Demographic and clinical data were collected contemporaneously. Radiographic and ultrasound images were obtained monthly and independently assessed by two experienced orthopaedic surgeons. Of the 42 initially enrolled patients 6 were lost to follow-up, resulting in the 36 included in the final cohort. There were 29 males and 7 females, aged between 22 and 64 years (mean, 39; median, 36.5). Fourteen fractures were open, with 20 classified as AO/OTA A, seven B, and nine C patterns. Of the 36 patients who completed the study, 31 healed uneventfully, while 5 did not achieve healing. An ultrasonographic bridging callus was observed between the first and third month following surgery. A "V"-shaped ultrasound corkscrew sign appeared in areas where no callus developed, and may serve as a prognostic factor for eventual nonunion. Bridging callus detected by ultrasound during the initial three months was identified as a positive prognostic indicator of bone healing. Ultrasonography is rarely used to assess fracture healing, but it may help predict outcomes. Portable point-of-care ultrasound (POCUS) can reduce radiation in follow-ups. Detecting bridging callus on ultrasound within three months reliably indicates bone healing, often appearing a month before seen on X-ray and suggesting eventual union.