Clinical study on the effect of low-intensity pulsed ultrasound on healing of proximal sesamoid bone fractures in Yili horses

The incidence of sports injuries in horses is increasing, thus accurate assessment, diagnosis, and treatment are critical. Among common sports-related injuries, proximal sesamoid bone fractures (PSBFs) are one of the most frequent types. To investigate the effects of low-intensity pulsed ultrasound (LIPUS) on imaging and hematological parameters of PSBFs, providing a clinical reference for the diagnosis and treatment of PSBFs in racehorses. After clinical diagnosis and radiographic examination confirmed the disease and its location, the affected horses were randomly divided into two groups: the ultrasound group received daily LIPUS treatment, while the control group received no intervention. After a four-week treatment, lameness grading, imaging, and hematological parameters were reassessed to evaluate PSBF healing and changes in blood indicators. Both imaging and hematological examinations play important clinical roles in the early diagnosis and later-stage evaluation of diseases. In this study, following LIPUS treatment, the affected horses showed significantly increased ALP activity in the serum, and higher levels of serum calcium (Ca), phosphorus (P), and the calcium-phosphorus product (Ca × P) (P < 0.05). Additionally, analysis of inflammatory cytokines revealed that the expression of pro-inflammatory markers, TNF-α, IL-1β, and IL-6, were markedly elevated during the early stages of fracture but gradually returned to normal as treatment progressed. These findings suggest that LIPUS can accelerate healing by alleviating inflammation at the fracture site. This study found that LIPUS treatment of PSBFs significantly improved microcirculation at the fracture site and promoted efficient healing through enhanced callus formation and accelerated bone repair. This favorable outcome of LIPUS therapy provides a valuable clinical reference for future diagnosis and treatment of PSBFs.