M02.9Reactive arthropathy, unspecified

M02.9 is the ICD-10-CM diagnosis code for reactive arthropathy, unspecified. It belongs to category M02 (postinfective and reactive arthropathies), block M00-M02 (infectious arthropathies) and chapter 13 (diseases of the musculoskeletal system and connective tissue). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within M02, choose M02.9 (Reactive arthropathy, unspecified) only when documentation doesn't support a more specific option: arthropathy following intestinal bypass (M02.0), Postdysenteric arthropathy (M02.1), Postimmunization arthropathy (M02.2), Reiter's disease (M02.3) and other reactive arthropathies (M02.8).

Code first underlying disease, such as: congenital syphilis [Clutton's joints] (A50.5), enteritis due to Yersinia enterocolitica (A04.6), infective endocarditis (I33.0) and viral hepatitis (B15-B19).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 553 (Bone Diseases and Arthropathies with MCC, relative weight 1.2494) and DRG 554 (Bone Diseases and Arthropathies without MCC, relative weight 0.8331), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is a manifestation code, so it describes the effect of an underlying disease and can't be the principal diagnosis. Code the underlying condition first.

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

Before ICD-10, this condition was coded in ICD-9-CM as 713.7 (other general diseases with articular involvement).