Abnormal head and neck carriage following trauma in a 5-month-old Thoroughbred colt

A 5-month-old Thoroughbred colt was referred to the equine service of the Veterinary Teaching Hos- pital of the University of Perugia with neck pain and abnormal head-neck posture of 2 days duration fol- lowing a fall over a fence in the paddock. After the traumatic episode, unilateral epistaxis was initially observed by the breeder, but no treatment was ren- dered following the trauma. At the time of admis- sion, he was bright and alert. The heart rate was 56 beats/min (reference range [RR], 60 to 80 beats/ min), the respiratory rate was 36 breaths/min (RR, 20 to 40 breaths/min), the rectal temperature was 38.1 °C (RR, 37.5 to 38.5 °C), and the mucous mem- branes were pink. A venous blood sample was col- lected aseptically for a hemogram and biochemical analyses. Hematology showed a moderate erythro- cytosis (16.1 X 109 RBCs/μL; RR, 6.4 X 109 to 10.4 X 109 RBCs/μL), an increased PCV (60.7%; RR, 30% to 47%), and a hemoglobin concentration of 20.6 g/ dL (RR, 10.7 to 16.5 g/dL). The biochemical param- eters showed slight hypoalbuminemia (2.8 g/dL; RR, 3.0 to 4.0 g/dL), hyperglobulinemia; (4.2 g/dL; RR, 1.8 to 3.6 g/dL), a moderately increased alanine aminotransferase (26 U/L; RR, 0 to 14 U/L), and an elevated serum amylase A (41 U/L; RR, 0 to 10 U/L). The neurologic evaluation, including the gait analysis, was normal. An overextended collum (neck) posture and a slight right-sided caput (head) tilt were identified, together with a painful swelling over the left regio retromandibularis (pharyngeal re- gion), between the mandible and the ventral margin of the atlas and axis. The colt did not show any dif- ficulties in lowering the head or eating. Based on the findings of the clinical examination, radiographic and ultrasonographic examinations of the head and cra- nial cervical spine were obtained (Figure 1).