Injury of accessory nerve, right side, sequela

This code signifies a long-term or late effect resulting from a previous injury to the right accessory nerve (cranial nerve XI). This could manifest as persistent weakness, atrophy, or impaired function of the sternocleidomastoid and trapezius muscles on the right side, impacting shoulder elevation and head rotation.

Apply this code when documenting a chronic or residual condition directly attributable to an old injury of the right accessory nerve. Documentation should clearly state the prior injury and the current, ongoing neurological deficit or functional impairment as a consequence.

• Always use an additional code to identify the specific sequela (e.g., muscle weakness, atrophy).
• Ensure documentation specifies "right side" and clearly indicates a "sequela" or "late effect" rather than an acute injury.
• Distinguish from acute accessory nerve injuries (S04.71XA, S04.71AD) which would use different 7th characters.