S04.21 Injury of trochlear nerve, right side

Non-billable ICD-10-CM code.

Applies from S04 Injury of cranial nerve

Applicable to

• The selection of side should be based on the side of the body being affected

Code first

• any associated intracranial injury (S06.-)

Code also

• any associated:
• open wound of head (S01.-)
• skull fracture (S02.-)

7th character note

• The appropriate 7th character is to be added to each code from category S04

7th character required

• A — initial encounter
• D — subsequent encounter
• S — sequela

Applies from S04.2 Injury of trochlear nerve

Applicable to

• Injury of 4th cranial nerve

Code annotations containing back-references to S04.21

Back-references to S04

• Code Also: G96.00 Cerebrospinal fluid leak, unspecified ("head injury (S00-S09)")
• Code Also: G96.08 Other cranial cerebrospinal fluid leak ("head injury (S00 - S09)")
• Code Also: G96.09 Other spinal cerebrospinal fluid leak ("head injury (S00 - S09)")
• Code Also: S01 Open wound of head ("injury of cranial nerve (S04.-)")

Nearby codes

• S04.2 Injury of trochlear nerve
• S04.20 Injury of trochlear nerve, unspecified side
• S04.20XA Injury of trochlear nerve, unspecified side, initial encounter
• S04.20XD Injury of trochlear nerve, unspecified side, subsequent encounter
• S04.20XS Injury of trochlear nerve, unspecified side, sequela
• S04.21 Injury of trochlear nerve, right side (this code)
• S04.21XA Injury of trochlear nerve, right side, initial encounter
• S04.21XD Injury of trochlear nerve, right side, subsequent encounter
• S04.21XS Injury of trochlear nerve, right side, sequela
• S04.22 Injury of trochlear nerve, left side
• S04.22XA Injury of trochlear nerve, left side, initial encounter