Exostoses on the palmar or plantar aspect of the diaphysis of the third metacarpal or metatarsal bone in horses: 16 cases (2001-2010).

The research investigates exostosis (a bony growth) on either the front or back of the metacarpal or metatarsal bone in horses, its symptoms, diagnosis, treatment, and the prognosis of affected horses. To do so, the researchers analyzed cases from 2001 to 2010.

Methodology

• The researchers went through records from 2001 to 2010 and selected 16 horses that showed signs of this abnormal bone growth through radiographic and ultrasonographic exams.
• The horses were further categorized based on the presence of lameness: 9 horses, noted as group A, had unilateral lameness (in one limb) that lessened with local or perineural analgesia while 7 horses, grouped as B, had inconsistent lameness in the affected limb.

Findings

• Through evaluations of these records, the authors found that the exostosis was located between the middle and far third of the bone in all horses.
• A condition known as desmopathy or peritendinous fibrosis (or both) at the site of the exostosis was identified in 6 of the horses.
• All the horses in group A were able to return to full function after treatment, whether it was surgical or conservative management.
• No recurrence of lameness was observed in any of the horses in group B, regardless of whether they received no treatment or only conservative management.

Conclusions

• The researchers concluded that an exostosis on either the front or back of the metacarpal or metatarsal bone could be a potential cause for lameness in horses.
• They suggest radiography and ultrasonography in combination with specific diagnostic analgesia for a reliable diagnosis.
• The prognosis for affected horses to return to athletic activity is generally good, but it can vary depending on whether there is concurrent desmopathy of the suspensory ligament, a structure that supports the lower leg of the horse.