Equine orbital fractures: a review of 18 cases (2006-2013).

OBJECTIVE: To review the clinical features, treatments, complications, and outcomes of horses with traumatic orbital fractures. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Eighteen horses with confirmed orbital fractures. PROCEDURES: Medical records of horses presenting with orbital fractures between 2006 and 2013 were reviewed. Signalment, etiology of fracture, clinical signs, fracture descriptions, diagnostic imaging, treatments, complications, and outcomes were evaluated. RESULTS: Eighteen horses presented with orbital fractures resulting from rearing in a confined space (n = 5), being kicked (4), colliding with a stationary object (3), and unknown trauma (6). Radiography and computed tomography were effective at classifying fractures and evaluating sinus/nasal involvement. Epistaxis/sinusitis were associated with fractures of the zygomatic process of the temporal bone (n = 3) and comminuted fractures of multiple bones (5). Seventeen fractures required treatment, with fifteen receiving a combination of medical and surgical therapy. Surgery included reduction of large bony fragments (n = 8), removal of small fragments (12), stabilization with a wire implant (1), and sinus trephination and lavage (5). Factors contributing to a favorable outcome included: globe retention (n = 16), vision (14), comfort (15), cosmesis (9), and return to previous function (13). CONCLUSIONS: Horses sustaining orbital fractures treated promptly with medical and surgical therapy have a favorable prognosis for return to function and cosmesis. Fractures affecting the zygomatic process of the frontal bone are unlikely to involve the sinus/nasal cavities. Epistaxis and sinusitis warrant more aggressive therapy and decrease functional and cosmetic outcome.

Surgical correction of severe strabismus and enophthalmos secondary to zygomatic arch fracture in a dog.

A grossly displaced segmental zygomatic arch fracture with marked ventro-lateral deviation of the left globe was diagnosed in a 3-month-old male German Shepherd dog following a bite injury. The fracture was approached via a modified lateral orbitotomy and a fragment of the lacrimal bone removed. The rostral portion of the fracture was stabilized with a 5-hole 2.0 dynamic compression plate bone plate. The surgical correction achieved sufficient skeletal fixation for proper anatomical reduction of the globe and excellent cosmetic and functional outcomes.

False ankylosis of the temporomandibular joint in a cat.

Progressive inability to open the mouth developed in a cat after trauma to the head. Evaluation revealed a healed depression fracture of the left zygomatic arch and normal temporomandibular joints. Surgical exploration of the fracture confirmed a false ankylosis that developed between the depression fracture and the ramus of the mandible. Treatment included excision of the central portion of the zygomatic arch and a portion of the ramus. The cat regained normal function of its mouth.

Periorbital skull fractures in five horses.

Periorbital skull fractures were diagnosed in 5 horses, and were associated with ophthalmic complications including corneal ulceration, uveitis, and entrapment of the eye by retrobulbar bone fragments. Physical examination was of greater diagnostic use than radiography. Surgical repair was performed on all horses and was associated with a more favorable postoperative appearance in horses treated acutely; however, the cosmetic results were considered acceptable in all horses. Major postoperative complications were not observed.

Surgical correction of temporomandibular joint ankylosis in two cats.

Two cats with temporomandibular joint ankylosis were examined. Difficulty in opening the mouth and malocclusion were associated with trauma and fracture around the zygomatic arch and the condyle of the mandible after an automobile accident. Unilateral condylectomy or aggressive caudal mandibulectomy was performed to improve quality of life. Excision arthroplasty of the temporomandibular joint improved mandibular function and appearance. Some malocclusion remained but had no clinical significance.

Traumatic tympanic bulla fracture.

A Pekingese dog was presented for evaluation of head trauma with ventral head and neck swelling, puncture wounds, palpable mandibular fractures, and loss of menace, severe miosis, and loss of palpebral reflex of the right eye. Computed tomography confirmed multiple mandibular and zygomatic fractures, a right ear canal avulsion, and a complete right tympanic bulla fracture with ventral displacement. The tympanic bulla fracture was managed conservatively. Topical lubrication and antibiotic ointment was prescribed for the right eye. A subtotal hemimandibulectomy was performed to address the mandibular fractures. A temporary oesophagostomy feeding tube was placed. No short-term complications developed as a result of the fractured bulla and avulsed ear canal being left in situ, and no complications were reported 18 months after the injury. To the authors' knowledge this is the first report of a traumatic tympanic bulla fracture in the dog.

Oculocardiac reflex induced by zygomatic arch fracture in a crossbreed dog.

A 3-year-old crossbreed male dog was presented with a history of blunt facial trauma. Skull radiographs showed right zygomatic arch fracture. An electrocardiogram revealed bradycardia, first-degree atrioventricular block and QT prolongation. Standard biochemical profile including electrolytes was normal. Atropine response test (0.04 mg/kg intravenously) restored normal sinus rhythm at a rate of 140 bpm with normal QT and PR intervals. This observation is consistent with oculocardiac reflex secondary to zygomatic arch fracture.