Application of a hook plate for management of equine ulnar fractures.

The research evaluated the effectiveness of using a hook plate to rectify closed fractures in the ulna of horses under or at 6 months old. Complications were sometimes encountered in this procedure, however, seven out of ten horses recovered and resumed athletic activities.

Objective and Methodology of the Study

• The study was centered on determining the utility of a hook plate as a treatment method for proximal ulnar fractures in equine subjects, specifically horses aged six months or younger. The system acted on a tension band principle.
• The fractures were categorized into five types (1A, 1B, 2, 3, and 4), with each classification having ten horses that underwent the hook plate procedure. All fractures in these categories exhibited displacement of a proximal fragment.

Findings and Complications of the Treatment

• The study set out several complications that arose from the treatment. These include implant deformation, observed in four horses, screw pullout in one horse, osseous sequestration (the isolation of a section of bone due to loss of blood supply) in one horse, and ulnar fracture through a hole used to apply a tension device in one horse.
• One horse suffered a metacarpophalangeal deformity linked to a displaced anconeal fragment.
• Hook deformation was found to likely root from the failure to insert screws in all of the proximal holes of the plate, and in two instances, difficult recovery from anesthesia was potentially related.

Results and Conclusion of the Study

• The results showed the treatment had a recovery rate of 70%, with seven of the ten horses discharged from the hospital and returned to athletic activities.
• The study concluded that the insertion of the hook through the tendon of the triceps muscle and incorporation of the fragment within the hook can be used to effectively reduce and stabilize a fragment that might otherwise not hold screws.