In a patient with a fracture of the orbital floor, which nerve is most likely affected, causing decreased sensation of the cheek?

In a patient with a fracture of the orbital floor, which nerve is most likely affected, causing decreased sensation of the cheek?

• A. Infraorbital nerve
• B. Zygomatic nerve
• C. Infraorbital artery
• D. Trigeminal nerve

Answer: (A)

The cheek sensation in this scenario is most likely lost because the infraorbital nerve carries sensory input from the midface, including the cheek, upper lip, and lower eyelid. This nerve is a branch of the maxillary division of the trigeminal nerve and travels through the infraorbital canal in the floor of the orbit, exiting at the infraorbital foramen. An orbital floor fracture can injure this nerve as it passes through the floor, leading to decreased sensation in the cheek. The zygomatic nerve can contribute some cheek sensation, but its disruption is less directly tied to the classic cheek numbness seen with an orbital floor fracture. The infraorbital artery is a blood vessel, not a nerve, so it wouldn’t account for sensory loss. The trigeminal nerve provides facial sensation overall, but the question points to the specific branch that traverses the orbital floor and supplies the cheek.

The cheek sensation in this scenario is most likely lost because the infraorbital nerve carries sensory input from the midface, including the cheek, upper lip, and lower eyelid. This nerve is a branch of the maxillary division of the trigeminal nerve and travels through the infraorbital canal in the floor of the orbit, exiting at the infraorbital foramen. An orbital floor fracture can injure this nerve as it passes through the floor, leading to decreased sensation in the cheek.

The zygomatic nerve can contribute some cheek sensation, but its disruption is less directly tied to the classic cheek numbness seen with an orbital floor fracture. The infraorbital artery is a blood vessel, not a nerve, so it wouldn’t account for sensory loss. The trigeminal nerve provides facial sensation overall, but the question points to the specific branch that traverses the orbital floor and supplies the cheek.