M84.4Pathological fracture, not elsewhere classified

M84.4 is the ICD-10-CM diagnosis code for pathological fracture, not elsewhere classified. It belongs to category M84 (disorder of continuity of bone), block M80-M85 (disorders of bone density and structure) and chapter 13 (diseases of the musculoskeletal system and connective tissue). It is a header code, so it can't be reported by itself; one of its 9 subcodes must be used instead.

Within M84 (disorder of continuity of bone), M84.4 is specifically for pathological fracture, not elsewhere classified. Related codes cover stress fracture (M84.3), pathological fracture in neoplastic disease (M84.5), pathological fracture in other disease (M84.6), nontraumatic fracture, not elsewhere classified (M84.7), other disorders of continuity of bone (M84.8) and unspecified (M84.9).

Codes in this range require a 7th character: A for initial encounter for fracture, D for subsequent encounter for fracture with routine healing, G for subsequent encounter for fracture with delayed healing, K for subsequent encounter for fracture with nonunion, P for subsequent encounter for fracture with malunion and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.

Don't report M84.4 together with the conditions in its Excludes1 note: collapsed vertebra NEC (M48.5), pathological fracture in neoplastic disease (M84.5-), pathological fracture in osteoporosis (M80.-), pathological fracture in other disease (M84.6-) and 2 more.

The conditions in its Excludes2 note aren't part of M84.4, but may be coded alongside it if the patient has both: personal history of (healed) pathological fracture (Z87.311).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.