M84.634A

Pathological fracture in other disease, left radius, initial encounter for fracture

FY2027Chapter 13: Diseases of the musculoskeletal system and connective tissue/M80–M85 Disorders of bone density and structure

BillableComplete code, valid to report

M84.634A (also written M84634A) is a billable ICD-10-CM diagnosis code for pathological fracture in other disease, left radius, initial encounter for fracture. 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, A, means initial encounter for fracture. Its coding notes include a Code also instruction, 1 Excludes1 entry and 11 Excludes2 entries.

7th character

Category M84.6 requires a 7th character.

Assembled code M84.634A Open code

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

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.

Guidelines I.C.13.cPathological fractures: the 7th characterRead the official text

Code also

Two codes may be needed to describe the condition. This note gives no sequencing order.

Inherited from M84.6 Pathological fracture in other disease
  • underlying condition

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from M84.6 Pathological fracture in other disease
  • pathological fracture in osteoporosis (M80.-)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Inherited from M84 Disorder of continuity of bone
  • traumatic fracture of bone-see fracture, by site
Also from chapter/block level (10 notes)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • 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.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the Musculoskeletal Rehabilitation clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

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 214 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 C

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition