Tenotomy of the semitendinosus muscle under standing sedation versus general anesthesia: Outcomes in 20 horses with fibrotic myopathy.

The study sets to compare the outcomes of tenotomy (a surgical operation involving the division of a tendon) on horses experiencing fibrotic myopathy which was performed under two different forms of anesthesia – standing sedation and general anesthesia.

Methods

• To make the comparison, medical records of 20 horses who underwent tenotomy between the period of 2002-2015 were examined.
• Several details such as breed, medical history, the muscles affected, the method used to keep the horse immobile during the surgery, the surgical procedures followed, and the short-term outcomes were pulled from the medical records.
• Furthermore, long-term outcomes regarding the horse’s gait and athletic function were assessed through conversations with the horse owners at least six months following the surgery.
• The study utilised Pearson’s χ statistical analysis to compare the method used to restrain the horse and the muscles affected with the overall outcome of the surgery. Statistical significance was set at P < .05.

Results

• The results showed that of the 20 horses whose records were examined, eight had undergone the surgical procedure under standing sedation while the remaining 12 were operated on under general anesthesia.
• In the horses where the semitendinosus muscle alone was affected, 8 out of 14 showed varying degrees of improvement. In the case of horses with both semitendinosus and semimembranosus muscles affected, four out of six showed improvement.
• When compared based on the type of anesthesia, six out of eight horses that were operated under standing sedation and six out of 12 horses that were operated under general anesthesia showed some degree of improvement in their fibrotic gait.
• In the case of athletic horses, five out of six horses that underwent surgery under standing sedation and six out of nine horses that were operated under general anesthesia returned to their pre-injury level of athleticism.
• Incisional complications were observed only in horses that were operated under general anesthesia. None of the horses operated under standing sedation had such complications.

Conclusions

• The study concludes that tenotomy of the semitendinosus muscle in horses suffering from fibrotic myopathy leads to similar improvement in gait. It found little material difference based on whether the procedure was performed under standing sedation or general anesthesia.