Management of an extensive equine juvenile ossifying fibroma by rostral mandibulectomy and reconstruction of the mandibular symphysis using String of Pearls plates with cortical and cancellous bone autografts

Abstract

Objective: To describe a surgical technique for rostral mandibulectomy and reconstruction of the mandibular symphysis.

Study design: Case report.

Animal: One 5-month-old warmblood cross filly.

Methods: A preoperative diagnosis of a juvenile ossifying fibroma was made on the basis of clinical appearance and was later confirmed via histology. The tumor was large, rapidly growing and extending to the caudal aspect of the mandibular symphysis. Computed tomography was performed for surgical planning. The tumor was excised by performing a mandibulectomy caudal to the symphysis. The mandibular symphysis was reconstructed with String of Pearls (SOP) plates. Cortex screws placed in lag fashion, a cortical bone graft from one of the mandibles and a cancellous graft harvested from the tuber coxae.

Results: At 9 months of age there was no sign of tumor reoccurrence, the implants were removed because of infection and the mandible had formed a new stable symphysis. The horse was able to prehend food and masticate normally. The owner was pleased with the cosmetic and functional outcome.

Conclusion: The described surgical technique is a viable option for mandibulectomy and reconstruction of the mandibular symphysis. The technique provided adequate stability for healing to occur in the face of infection.

Clinical significance: Neoplasia and other conditions affecting the entire mandibular symphysis can be treated by complete surgical excision and reconstruction.