The successful repair of a complete fracture of a cannon bone in a circus pony by inserting a single metal plate has been described by veterinarians in Portugal.
Complete fractures of the third metacarpal are responsible for about a third of all long-bone fractures in the horse, mostly related to external trauma or to high-energy injuries.
The scientific literature shows that such fractures have been repaired through stabilization and the internal use of two bone plates.
Isabel Dias and her colleagues, writing in the Open Veterinary Journal, described the repair of the break in a 7-year-old Shetland circus pony using a single bone plate.
The 103kg animal, who had been struck by a truck, was fully recovered after three months.
The pony was agitated and seemingly unable or unwilling to stand when he was admitted to the Veterinary Teaching Hospital of University of Tras-os-Montes and Alto Douro. He had a small penetrating wound on his right hindlimb. X-rays revealed a complete fracture, with one end of the broken bone offset to the side.
The owner opted for surgical repair. During the procedure under general anaesthetic, one eight-hole compression plate, contoured to the side face of the bone, was used the stabilize the fracture, with four screws employed above the break and three in the lower section.
The pony received post-operative antibiotics and pain relief following surgery. X-rays were taken periodically to monitor the break.
The entire limb was placed in a cast following surgery and the pony was kept under movement limitations for four weeks.
The animals stayed at the hospital until his full recovery three months after surgery.
At this point, due to slight lameness and swelling of the nearby joint, and since the bone repair was apparent in the x-rays, it was decided to remove the internal implants.
He returned to his previous level of exercise without any significant post-operative complications or degree of lameness, the study team reported.
“The originality of this clinical case results from the fact that for small equids of this weight, even with an extremely demanding physical activity such as in the present case, the option of a single plate can be used, instead of double plating, reducing the cost and risk of infection.”
The case-report team comprised Dias, Luís Maia, Miguel Quaresma, Mário Cotovio and Filipe Silva, all affiliated with the University of Trás-os-Montes and Alto Douro in Vila Real, Portugal.
Laterally applied single bone plate option for fixation of complete diaphyseal fracture of a third metatarsal bone in a circus work pony
Isabel R. Dias, Luís M. Maia, Miguel Quaresma, Mário Cotovio, Filipe C. Silva
Open Veterinary Journal, (2021), Vol. 11(4): 645–650 DOI: 10.5455/OVJ.2021.v11.i4.14