What are the symptoms of nerve damage caused by injection?

Generally speaking, injections will not damage nerves. Of course, if in special circumstances, nerves are damaged after an injection, you may experience discomfort when walking, and symptoms such as numbness, swelling, and pain. Nerve damage is extremely harmful to human health and is difficult to treat, so too much attention needs to be paid to the protection of the nerves. Try to avoid injuries and strengthen your lifestyle adjustments.

Classification of cranial nerve damage

(1) Olfactory nerve damage

There are often symptoms of ethmoid sinus fracture or frontal-basal brain contusion, such as cerebrospinal fluid leak and partial or complete unilateral or bilateral loss of smell.

(2) Optic nerve damage

It is often accompanied by anterior and middle cranial fossa fractures involving the orbital apex and optic canal. Immediately after the injury, the patient experiences decreased vision or even blindness, direct light reflex disappears, and indirect light reflex is normal. If the optic chiasm is damaged, binocular vision will be impaired and visual field will be lost.

(3) Injury to oculomotor, trochlear, abducens and ophthalmic branch of trigeminal nerve

Fractures of the lesser wing of the sphenoid bone, petrous part of the temporal bone, and maxillofacial region are common. Patients with oculomotor nerve injury may experience diplopia, ptosis, pupil dilation, loss of light reflex, and eye deviation to the outside and below; patients with trochlear nerve injury may experience diplopia when gazing downward.

Injury to the abducens nerve may cause limited eye abduction and strabismus; injury to the trigeminal nerve may cause loss of corneal reflex, facial sensory disturbance, chewing weakness, and occasionally trigeminal neuralgia.

There are often fractures of the petrous part and foramen of the temporal bone, and symptoms such as facial paralysis, loss of taste in the anterior 2/3 of the tongue on the same side, keratitis, tinnitus, vertigo, and sensorineural hearing loss may appear at different times after the injury.

(5) Injury to the glossopharyngeal, vagus, accessory, and hypoglossal nerves

Rarely occurs. Occipital bone fractures are common. Symptoms include difficulty in swallowing, disappearance of pharyngeal reflex, loss of taste in the posterior 1/3 of the tongue, hoarseness, drooping shoulders, atrophy of the tongue muscles on the injured side, and tongue extension tending to the affected side.