Fibrotic myopathy of the semitendinosus muscle in a thoroughbred foal

Fibrotic myopathy of the semitendinosus muscle was diagnosed in a 9-months-old female thoroughbred foal on the left hindleg. The cranial phase of the stride was shortened than normal and the foot was suddenly pulled caudally just before contacting to the ground during walking. A non-painful firmness area was palpated over the semitendinosus muscle on the caudal surface of the left hindleg above at the level of the stifle joint. Tenotomy of the tibial insertion of the semitendinosus muscle was undergone. The foal returned to the normal exercise one month after surgery