Dermoid cysts formation is a complication of wound pinch grafting in a horse: A case report.

Objectives: To describe dermoid cyst formation as an uncommon complication of the pinch grafting technique in horses.

Study design: Case report.

Animal: A 8 year old Arabian gelding.

Methods: Clinical presentation, imaging, treatment, and histopathology records were reviewed. The horse originally presented due to delayed healing of a laceration to the distal aspect of the metatarsus. The wound was treated initially with debridement and it was allowed to fill with healthy granulation tissue prior to pinch grafting. Two months after grafting, the horse started to show self-mutilation behavior targeting the wound site. Ultrasonographic examination revealed the presence of cystic lesions in the subcutaneous tissue in the wound bed and adjacent to the long digital extensor tendon.

Results: Treatment involved surgical excision of the cysts, which resulted in a resolution of the self-mutilation episodes. The specimens were submitted for histopathological investigation, which revealed findings compatible with dermoid cyst formation, suspected to be secondary to the skin-grafting procedure.

Conclusion: Dermoid cysts formation should be considered as a potential differential diagnosis for skin graft complications in horses.