M87.859 — Other osteonecrosis, unspecified femur
Is M87.859 billable?
Yes, but M87.859 will trip a Medicare edit. M87.859 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, CMS lists M87.859 under Medicare Code Editor edit 20, “Unspecified code” — meaning a code specifying laterality (right, left or bilateral) exists in the same family. On an inpatient claim this triggers the edit, because CMS holds that there are very limited circumstances in which laterality cannot be documented.
M87.859 at a glance
| Code | M87.859 |
|---|---|
| Description | Other osteonecrosis, unspecified femur |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to M87.859?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name M87.859 directly.
A code specifying laterality (right, left or bilateral) exists in the same family. CMS holds that there are very limited circumstances in which laterality cannot be documented.
Which MS-DRGs does M87.859 group to?
M87.859 sits in MDC 08 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 553Bone Diseases and Arthropathies with MCCmedical
- 554Bone Diseases and Arthropathies without MCCmedical
As a secondary diagnosis, M87.859 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is M87.859 listed in the Alphabetic Index?
The Alphabetic Index lists these routes under M87.85, the nearest indexed parent of M87.859. Use them to find the family, then select the specific code.
- Osteonecrosis › specified type NEC › femur
Excludes1 — never code together — inherited from M86-M90
The conditions below can never be reported together with M87.859 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- postprocedural osteopathies (M96.-)
Excludes1 — never code together — inherited from M87
The conditions below can never be reported together with M87.859 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from M87
Report an additional code alongside M87.859 to fully describe the condition. M87.859 is sequenced first.
- code to identify major osseous defect, if applicable (M89.7-)
Excludes2 — not included here — inherited from Chapter 13
The conditions below are not part of M87.859, but a patient may have both at the same time. When documentation supports it, M87.859 and the excluded code may both be reported.
- arthropathic psoriasis (L40.5-)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- compartment syndrome (traumatic) (T79.A-)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
How long has M87.859 existed?
M87.859 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.