M90.55

Osteonecrosis in diseases classified elsewhere, thigh

Not billable — category only FY2026 2025-10-01 → 2026-09-30

Exclusions 19 never code together

M90code

Excludes1

osteochondritis, osteomyelitis, and osteopathy (in):
cryptococcosis (B45.3)B45.3
diabetes mellitus (E08-E13 with .69-)E08-E13
gonococcal (A54.43)A54.43
neurogenic syphilis (A52.11)A52.11
renal osteodystrophy (N25.0)N25.0
salmonellosis (A02.24)A02.24
secondary syphilis (A51.46)A51.46
syphilis (late) (A52.77)A52.77

Excludes2

arthropathic psoriasis (L40.5-)L40.5-
certain conditions originating in the perinatal period (P04-P96)P04-P96
certain infectious and parasitic diseases (A00-B99)A00-B99
compartment syndrome (traumatic) (T79.A-)T79.A-
complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
neoplasms (C00-D49)C00-D49
symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94

Excludes1 — never code together. The excluded condition and this one are mutually exclusive.

Excludes2 — not included here, but the patient may have both. Code both when documented.

Instructional notes 4

Code first

Notes

Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

Index entries leading here filed at null

No alphabetic index entry points at this code.

Alongside this code 9 same parent — M90.5

Subordinate codes 3

Additional references

AHA Coding Clinic® Licence required

Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.

Maps to no condition category in any loaded model.

Presence is a property of the code. Untick a model to hide it everywhere.

Present FY2024–FY2027.