A 16-year-old boy is brought to the emergency department after an eye injury during a baseball game. He was batting for his high school team when the opposing pitcher made a wild throw and the baseball hit him in the right eye. The patient has since been having diplopia that worsens when he looks up. On physical examination, he has mild periorbital ecchymosis, enophthalmos, and limited vertical movement of the right eye. Visual acuity and left eye examination are normal. CT scan of the head reveals an orbital floor fracture. Which of the following additional findings is most likely to be seen in this patient?

Question

A 16-year-old boy is brought to the emergency department after an eye injury during a baseball game.  He was batting for his high school team when the opposing pitcher made a wild throw and the baseball hit him in the right eye.  The patient has since been having diplopia that worsens when he looks up.  On physical examination, he has mild periorbital ecchymosis, enophthalmos, and limited vertical movement of the right eye.  Visual acuity and left eye examination are normal.  CT scan of the head reveals an orbital floor fracture.  Which of the following additional findings is most likely to be seen in this patient?

Quizplus · Accepted Answer

11ec160b_35be_7c03_9249_bd7930bf6a71_MD0001_00 Fractures to the orbital floor, which is composed of the zygomatic bone and maxilla, most commonly result from direct frontal trauma to the orbit due to assault, motor vehicle crashes, or sports injuries. The infraorbital nerve (continuation of the maxillary nerve) runs along the orbital surface of the maxilla in the infraorbital groove before traversing the infraorbital canal and exiting the skull via the infraorbital foramen (just below the orbit). Damage can result in numbness and paresthesia of the upper cheek, upper lip, and upper gingiva. In addition, displacement of the orbital contents through the floor may cause enophthalmos, and entrapment of the inferior rectus muscle (as seen in above CT) can impair vertical gaze. (Choice A) The corneal reflex involves cranial nerves V₁ (sensory) and VII (motor) and processing in the pons. It can be impaired by trauma to the superior orbital fissure because cranial nerves III, IV, V, and VI pass through this structure. (Choice B) Hematomas over the mastoid process (Battle sign), along with periorbital ecchymosis and clear otorrhea, are signs of basilar skull fractures. (Choice C) Nasal fractures or high force trauma to the midface can result in loss of smell if the olfactory nerves are torn from the cribriform plate in the ethmoid bone. (Choice D) The facial nerve (cranial nerve VII) controls the motor function of the face and can be impaired in fractures of the temporal bone after lateral head trauma or zygomatic orbit fractures. Educational objective: Fractures to the orbital floor commonly result from direct frontal trauma to the orbit. The infraorbital nerve runs along the orbital floor in a groove in the maxilla before exiting the skull just inferior to the orbit. Damage can result in paresthesia of the upper cheek, upper lip, and upper gingiva. In addition, the inferior rectus muscle can also become entrapped, limiting vertical gaze. __________ References: Orbital fractures: a review. (http://www.ncbi.nlm.nih.gov/pubmed/21339801) Pediatric orbital fractures. (http://www.ncbi.nlm.nih.gov/pubmed/24436730)

A 16-Year-Old Boy Is Brought to the Emergency Department After