Is S82.021 a billable ICD-10-CM code?

No. S82.021 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does S82.021 sit in the tabular list?

Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Injuries to the knee and lower leg (S80-S89).

What cannot be coded together with S82.021?

S82.021 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above S82.021 (S82) and apply to it just the same.

S82.021

S82.021 — Displaced longitudinal fracture of right patella

Non-billable headerICD-10-CMright

S82.021 is a non-billable header ICD-10-CM code for displaced longitudinal fracture of right patella. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

The appropriate 7th character is to be added to all codes from category S82

A: initial encounter for closed fracture
B: initial encounter for open fracture type I or II
C: initial encounter for open fracture type IIIA, IIIB, or IIIC
D: subsequent encounter for closed fracture with routine healing
E: subsequent encounter for open fracture type I or II with routine healing
F: subsequent encounter for open fracture type IIIA, IIIB, or IIIC with routine healing
G: subsequent encounter for closed fracture with delayed healing
H: subsequent encounter for open fracture type I or II with delayed healing
J: subsequent encounter for open fracture type IIIA, IIIB, or IIIC with delayed healing
K: subsequent encounter for closed fracture with nonunion
M: subsequent encounter for open fracture type I or II with nonunion
N: subsequent encounter for open fracture type IIIA, IIIB, or IIIC with nonunion
P: subsequent encounter for closed fracture with malunion
Q: subsequent encounter for open fracture type I or II with malunion
R: subsequent encounter for open fracture type IIIA, IIIB, or IIIC with malunion
S: sequela

Excludes1 inherited from the categories above S82.021

These are not written on S82.021, but they bind it: a note on a category applies to every code beneath it. Billing S82.021 with anything listed here is a denial.

Written on S82 — Fracture of lower leg, including ankle

traumatic amputation of lower leg (S88.-)

Excludes2 inherited from the categories above S82.021

Also inherited, and the opposite of Excludes1: these conditions are not part of S82.021, but a patient can have both, so you may code both.

Written on S82 — Fracture of lower leg, including ankle

fracture of foot, except ankle (S92.-)
periprosthetic fracture around internal prosthetic ankle joint (M97.2)
periprosthetic fracture around internal prosthetic implant of knee joint (M97.1-)

Other codes that can never be billed with S82.021

These codes carry an Excludes1 note pointing at S82.021. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading S82.021 alone.

M84.3Stress fracture
M84.4Pathological fracture, not elsewhere classified
S81Open wound of knee and lower leg

Risk adjustment

S82.021 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code history

S82.021 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Code to one of these instead S82.021

16 child codes. Green means billable.

Related codes at this level

Codes that share S82.02. If S82.021 is not quite right, the correct code is usually one of these.

Questions about S82.021

Is S82.021 a billable ICD-10-CM code?: No. S82.021 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does S82.021 sit in the tabular list?: Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Injuries to the knee and lower leg (S80-S89).
What cannot be coded together with S82.021?: S82.021 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above S82.021 (S82) and apply to it just the same.