2027 ICD-10-CM Diagnosis Code M84.575KPathological fracture in neoplastic disease, left foot, subsequent encounter for fracture with nonunion
ICD-10-CM Codes›M00–M99›M80-M85›M84
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- 7th Character K — Subsequent, Nonunion
- Chronic Condition
M84.575K is a billable ICD-10-CM diagnosis code for pathological fracture in neoplastic disease, left foot, subsequent encounter for fracture with nonunion. The 7th character K means subsequent encounter for fracture with nonunion. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 564 through 566. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 5,561 closely related codes. Coders also document this condition as neoplasm of bone of left foot. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pathological fracture, subsequent encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Neoplasm of bone of left foot
- Pathologic fracture of bone of foot at site of neoplasm
- Pathological fracture of left foot
- Pathological fracture of left foot at site of neoplasm
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to M84.575K: its own notes plus those printed at M84.5, M84, and Chapter 13. A note printed at a category, block or chapter applies to every code under it.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- traumatic fracture of bone-see fracture, by site
- 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)
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
- underlying neoplasm
Notes
General instructions on how these codes are used.
- Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
7th Character
Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.
- The appropriate 7th character is to be added to each code from subcategory M84.5:
- Ainitial encounter for fracture
- Dsubsequent encounter for fracture with routine healing
- Gsubsequent encounter for fracture with delayed healing
- Ksubsequent encounter for fracture with nonunion this code
- Psubsequent encounter for fracture with malunion
- Ssequela
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name M84.575K, its category, or a range that includes it.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Foot Injuries and Disorders
Each of your feet has 26 bones, 33 joints, and more than 100 tendons, muscles, and ligaments. No wonder a lot of things can go wrong. Here are a few common problems:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert M84.575K to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About M84.575KOverview
Is M84.575K (Pathological fracture in neoplastic disease, left foot) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report pathological fracture in neoplastic disease, left foot, subsequent encounter for fracture with nonunion on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What does the 7th character K in M84.575K mean?
The final character K reports a subsequent encounter where the pathological fracture in neoplastic disease, left foot has failed to heal, called a nonunion. In this category the CMS Tabular List defines K as "subsequent encounter for fracture with nonunion".
What MS-DRG does M84.575K group to?
When pathological fracture in neoplastic disease, left foot, subsequent encounter for fracture with nonunion is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 566, 565, with relative weights from 0.7374 to 1.4909 depending on complications. Higher weights mean higher Medicare reimbursement.
Is M84.575K a CC or MCC?
CMS lists M84.575K as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 5,561 closely related codes in its exclusion list.
What is the ICD-9 equivalent of M84.575K?
Under the General Equivalence Mappings, pathological fracture in neoplastic disease, left foot, subsequent encounter for fracture with nonunion converts to ICD-9-CM 733.82 (nonunion of fracture). The mapping is approximate, so confirm the match fits the documentation.
