Return to sport activity following ultrasonographic diagnosis and conservative management of spontaneous injuries of the serratus cervicis ventralis and serratus thoracis ventralis muscles in 11 endurance horses.

The research examines the diagnosis, ultrasound findings, and outcomes of 11 endurance horses that suffered injuries to their serratus ventralis thoracis (SVT) or serratus ventralis cervicis (SVC) muscles. It was found that these injuries were effectively diagnosed using ultrasound, and through conservative management, all horses were able to return to full training and competition.

Clinical Diagnosis

• The 11 endurance horses were participating in medium- to high-level competitions when they presented with lameness caused by injuries to the SVT or SVC muscle.
• Physical examinations showed that horses with SVT injuries had swelling behind the shoulder region, a dorsocranial displacement of the scapula, and edema (fluid retention) of the ventral thorax.
• Horses with SVC injuries were identified by swelling in front of the scapula and edema of the pectoral area.

Dynamic Examinations and Ultrasonography

• Dynamic examinations showed a moderate-to-severe reduction in the forward phase of the stride during walking; during trotting, a lameness score of 2 to 3 out of 5 was given, based on the modified American Association of Equine Practitioners Lameness Scale.
• Ultrasonography showed moderate-to-severe increases in the size of the muscle body, heterogenicity in echogenicity (the ability to reflect ultrasound waves), loss of the striated muscle pattern, and various degrees of perimuscular edema.

Outcome and Recovery

• All horses were able to resume full training and competition after conservative management of their injuries. The average recovery times were 216 days (range 74 to 362 days) for SVT injuries and 148 days (range 112 to 309 days) for SVC injuries.

Conclusions and Significance

• This study is the first of its kind to describe the clinical and ultrasonographic features of spontaneous injuries to the SVT or SVC in horses.
• The use of ultrasonography for diagnosis was found to be straightforward and well received by the horses, representing a considerable advancement in the management of such injuries in equine practice.