Porcupine Quill Migration Into the Temporomandibular Joint Causing Trismus in a Dog.

Porcupine quill injuries have been reported in the veterinary literature as the source of a wide range of complications affecting separate body regions and organ systems, particularly in dogs from specific geographic locations. However, migration of porcupine quills involving the temporomandibular joint and its clinical consequences have not been previously reported. This report describes the first documented case of a dog presenting with trismus and a draining tract in the area of the left zygomatic arch several weeks following a porcupine encounter. The dog was referred as a consequence of the unsuccessful initial management of the injuries and the associated clinical signs. For this reason, advanced diagnostic imaging, including ultrasonography and computed tomography, was performed to investigate the possible cause. Surgical management for resolution of the clinical signs involved resection of the zygomatic arch, followed by partial resection of the lateral aspect of the mandibular condylar process for retrieval of the quill fragments.