Nerve supply to the nose is externally derived from branches of the trigeminal nerve. The skin of the nose superiorly at the radix and rhinion is supplied from branches of the supratrochlear termination of the ophthalmic nerve. The anterior ethmoidal nerve, another branch of the ophthalmic, may traverse the dorsum of the nose to supply the tip . In endonasal or in open rhinoplasty, this nerve bundle may be damaged by over-aggressive endonasal incisions violating the fibromuscular layer, or elevation of the S-STE (skin-soft tissue envelope) in the wrong plane, resulting in a numb nasal tip. The infraorbital nerve may also contribute branches to the lateral nasal walls, columella, and vestibule. Knowledge of this external nerve supply is necessary to perform adequate nerve blocks for closed reductions, or for rhinoplasty under local anesthesia with sedation. Intranasal anesthesia is also a prerequisite for these procedures. This may be performed with intranasal cocaine pledgets or other strategically placed topical anesthetics. Perhaps the most important target is the sphenopalatine ganglion located in the posterior portion of the nose just posterior to the middle turbinate. Internal branches of the anterior ethmoid must also be anesthetized in the superior portion of the nose to complete a total nasal block.
*1 Traumatic neuroma follows different forms of nerve injury (often as a result of surgery). They occur at the end of injured nerve fibres as a form of ineffective, unregulated nerve regeneration; it occurs most commonly near a scar, either superficially (skin, subcutaneous fat) or deep (e.g., after a cholecystectomy). They are often very painful. Synonyms include scar neuroma, amputation neuroma, or pseudoneuroma.