S84.91 – Injury of unspecified nerve at lower leg level, right leg

ICD-10-CM 2027 diagnosis code · Injuries to the knee and lower leg

Non-billable header

ICD-10-CM code S84.91

Code: S84.91 (claims format: S8491)
Description: Injury of unspecified nerve at lower leg level, right leg
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 19. Injury, poisoning and certain other consequences of external causes (S00-T88)
Block: S80-S89 Injuries to the knee and lower leg
Parent codes: S84 › S84.9

Billable codes under S84.91

S84.91 is a header code and cannot be used on claims. Choose the most specific code:

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care (use placeholder X for empty positions).

Character	Meaning
`A`	initial encounter
`D`	subsequent encounter
`S`	sequela

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

S84 – Injury of nerves at lower leg level

Excludes2 (not included here):

injury of nerves at ankle and foot level (S94.-)

Code also:

any associated open wound (S81.-)

7th character note:

The appropriate 7th character is to be added to each code from category S84

Block S80-S89

Excludes2 (not included here):

burns and corrosions (T20-T32)
frostbite (T33-T34)
injuries of ankle and foot, except fracture of ankle and malleolus (S90-S99)
insect bite or sting, venomous (T63.4)

Related codes in S84.9

Frequently asked questions

What is ICD-10 code S84.91?

S84.91 is the ICD-10-CM code for injury of unspecified nerve at lower leg level, right leg, in the block S80-S89 (Injuries to the knee and lower leg).

Is S84.91 a billable code?

No. S84.91 is a header code with more specific child codes; report one of the billable codes listed above.

What category does S84.91 belong to?

It belongs to category S84 – Injury of nerves at lower leg level.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.