M84.439A — Pathological fracture, unspecified ulna and radius, initial encounter for fracture
Is M84.439A billable?
Yes, but M84.439A will trip a Medicare edit. M84.439A is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, CMS lists M84.439A 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.
More specific alternatives
M84.439A at a glance
| Code | M84.439A |
|---|---|
| Description | Pathological fracture, unspecified ulna and radius, initial encounter for fracture |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter for fracture |
What does the 7th character "A" mean in M84.439A?
In M84.439A, the 7th character A means initial encounter for fracture. The 7th character is required for M84.439A to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
What Medicare edits apply to M84.439A?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name M84.439A 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 M84.439A group to?
M84.439A sits in MDC 08 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 542Pathological Fractures and Musculoskeletal and Connective Tissue Malignancy with MCCmedical
- 543Pathological Fractures and Musculoskeletal and Connective Tissue Malignancy with CCmedical
- 544Pathological Fractures and Musculoskeletal and Connective Tissue Malignancy without CC/MCCmedical
As a secondary diagnosis, M84.439A is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is M84.439A listed in the Alphabetic Index?
The Alphabetic Index lists these routes under M84.43, the nearest indexed parent of M84.439A. Use them to find the family, then select the specific code.
- Fracture, pathological › radius (pathologic)
- Fracture, pathological › ulna (pathologic)
Excludes1 — never code together — inherited from M84.4
The conditions below can never be reported together with M84.439A on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 13
The conditions below are not part of M84.439A, but a patient may have both at the same time. When documentation supports it, M84.439A 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)
Excludes2 — not included here — inherited from M84
The conditions below are not part of M84.439A, but a patient may have both at the same time. When documentation supports it, M84.439A and the excluded code may both be reported.
- traumatic fracture of bone-see fracture, by site
Excludes2 — not included here — inherited from M84.4
The conditions below are not part of M84.439A, but a patient may have both at the same time. When documentation supports it, M84.439A and the excluded code may both be reported.
- personal history of (healed) pathological fracture (Z87.311)
How long has M84.439A existed?
M84.439A 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.