Is Q77.4 a billable ICD-10-CM code?

Yes. Q77.4 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does Q77.4 sit in the tabular list?

Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations and deformations of the musculoskeletal system (Q65-Q79).

What cannot be coded together with Q77.4?

Q77.4 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 Q77.4 (Q77) and apply to it just the same.

Q77.4

Q77.4 — Achondroplasia

Billable / specific codeICD-10-CMPOA exempt

Q77.4 is a billable, specific ICD-10-CM code for achondroplasia. It is valid for submission on a claim.

Inclusion terms

Alternative wordings a physician may use in the chart for this same code.

Hypochondroplasia
Osteosclerosis congenita

Excludes1 inherited from the categories above Q77.4

These are not written on Q77.4, but they bind it: a note on a category applies to every code beneath it. Billing Q77.4 with anything listed here is a denial.

Written on Q77 — Osteochondrodysplasia with defects of growth of tubular bones and spine

mucopolysaccharidosis (E76.0-E76.3)

Excludes2 inherited from the categories above Q77.4

Also inherited, and the opposite of Excludes1: these conditions are not part of Q77.4, but a patient can have both, so you may code both.

Written on Q77 — Osteochondrodysplasia with defects of growth of tubular bones and spine

congenital myotonic chondrodystrophy (G71.13)

Other codes that can never be billed with Q77.4

These codes carry an Excludes1 note pointing at Q77.4. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading Q77.4 alone.

E34.3Short stature due to endocrine disorder
M85.8Other specified disorders of bone density and structure

Risk adjustment

Q77.4 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.

How Q77.4 is indexed

Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to Q77.4.

Achondroplasia(osteosclerosis congenita)
Chondrogenesis imperfecta
Hypochondroplasia
Chondrodysplasia›fetalis
Dwarfism›achondroplastic
Dwarfism›hypochondroplastic
Osteosclerosis›congenita

Code history

Q77.4 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Related codes at this level

Codes that share Q77. If Q77.4 is not quite right, the correct code is usually one of these.

Questions about Q77.4

Is Q77.4 a billable ICD-10-CM code?: Yes. Q77.4 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does Q77.4 sit in the tabular list?: Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations and deformations of the musculoskeletal system (Q65-Q79).
What cannot be coded together with Q77.4?: Q77.4 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 Q77.4 (Q77) and apply to it just the same.