M84.529P
Pathological fracture in neoplastic disease, unspecified humerus, subsequent encounter for fracture with malunion
M84.529P (also written M84529P) is a billable ICD-10-CM diagnosis code for pathological fracture in neoplastic disease, unspecified humerus, subsequent encounter for fracture with malunion. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 928 codes in category M84 (Disorder of continuity of bone). Its 7th character, P, means subsequent encounter for fracture with malunion. Its coding notes include a Code also instruction and 11 Excludes2 entries.
7th character
Category M84.5 requires a 7th character.
Guidelines tips
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Sequencing depends on the focus of treatment: the fracture or the neoplasm.
7th character A applies while the patient is in active treatment, regardless of which provider sees them. D is for routine care during healing after active treatment ends.
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
- underlying neoplasm
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
- traumatic fracture of bone-see fracture, by site
Also from chapter/block level (10 notes)
- 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)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 5,561 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CNotes
Also from chapter/block level (1 note)
- Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition