A patient with left-sided facial palsy of LMN type following parotid surgery has complete transection of the main trunk of the facial nerve proximal to the pes anserinus. The expected House-Brackmann grade immediately post-operatively and the recommended timing of nerve repair are:

• A House-Brackmann VI; nerve repair within 72 hours ✓
• B House-Brackmann IV; nerve repair at 3 months
• C House-Brackmann VI; nerve repair at 12 months
• D House-Brackmann V; primary repair can wait up to 6 months

Explanation

Complete transection of the facial nerve main trunk causes immediate House-Brackmann Grade VI (complete paralysis — no movement whatsoever). Immediate or early (within 72 hours) primary end-to-end neurorrhaphy (or interposition nerve graft if gap exists) gives the best functional outcomes, with potential recovery to Grade III–IV. The critical window is before Wallerian degeneration progresses and muscle fibrosis begins; distal nerve stumps can be identified electrically for up to 72 hours post-injury. If primary repair is impossible, cable graft using great auricular or sural nerve is performed. Delayed repair (>12 months) has significantly poorer outcomes due to irreversible motor end plate degeneration.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.