Tenotomy of the tibial insertion of the semitendinosus muscle of two horses with fibrotic myopathy

Minimally invasive tenotomy of the tibial insertion of the semitendinosus muscle: An ex vivo study in horses

OBJECTIVE

To describe a minimally invasive technique for semitendinosus tenotomy with ultrasonographic guidance and to evaluate procedural complications.

STUDY DESIGN

Experimental study.

SAMPLE POPULATION

Cadaveric equine hind limbs (n = 16).

METHODS

A stab incision was performed distocaudal to the tibial insertion of the semitendinosus muscle with ultrasonographic assistance. After transection of the tendon with an arthroscopic retrograde knife, the tendon edges palpably retracted, and complete transection was confirmed by ultrasound. Limbs were dissected to confirm the degree of tendon transection and to identify iatrogenic trauma to surrounding soft tissues.

RESULTS

Tenotomy was complete in all limbs, resulting in a palpable gap forming between tendon edges. Superficial iatrogenic laceration to the underlying gracilis muscle (n = 2) or gracilis fascia (n = 1) was apparent in 3 of 16 limbs.

CONCLUSION

Ultrasound-assisted tenotomy of the tibial insertion of the semitendinosus muscle was reliably performed in a minimally invasive fashion with minor iatrogenic damage.

CLINICAL SIGNIFICANCE

Minimally invasive tenotomy of the semitendinosus muscle can be performed with ultrasonographic assistance and should be considered as an alternative technique for surgical management of fibrotic semitendinosus myopathy.

Standing myotomy to treat fibrotic myopathy: 22 cases (2004-2016)

OBJECTIVE

To report the clinical and diagnostic findings associated with fibrotic myopathy, describe the surgical procedure for standing fibrotic myotomy and report postoperative outcomes.

STUDY DESIGN

Retrospective study.

SAMPLE POPULATION

Twenty-two horses.

METHODS

Records were included if a clinical diagnosis of fibrotic myopathy was based on clinical and/or ultrasonographic examination and the horse was treated with myotomy of the affected muscle. Records were reviewed for signalment, preoperative findings, perioperative complications, and outcomes. Follow-up also included a phone survey of owners.

RESULTS

Quarter horses represented 14 of 22 horses in this study. Ultrasonographic examination was performed in 14 of 22 horses. The semitendinosus muscle was affected in 17 of 22 horses. Other muscles affected included the semimembranosus, gracilis, and biceps femoris. Four of the 22 horses had a diagnosis of incisional postoperative complications. Eight of 12 formerly athletic horses returned to their intended athletic use. Ten of 16 owners were satisfied with the procedure.

CONCLUSION

Prognosis for long-term comfort after standing fibrotic myotomy was fair with appropriate rehabilitation. Ultrasonographic examination was helpful in identifying the muscles affected and aided in surgical planning.

CLINICAL IMPACT

Standing fibrotic myotomy is a technically straightforward procedure that yields a fair outcome in horses with minimal intraoperative and/or postoperative complications.