ICD-10 code for primary myopathy

The ICD-10-CM code for primary myopathy is G71.9 (Primary disorder of muscle, unspecified). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on G71.9.

Within G71, choose G71.9 (Primary disorder of muscle, unspecified) only when documentation doesn't support a more specific option: muscular dystrophy (G71.0), myotonic disorders (G71.1), congenital myopathies (G71.2), mitochondrial myopathy, not elsewhere classified (G71.3) and other primary disorders of muscles (G71.8).

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 091 (Other Disorders of Nervous System with MCC, relative weight 1.7046), DRG 092 (Other Disorders of Nervous System with CC, relative weight 1.0239) and DRG 093 (Other Disorders of Nervous System without CC/MCC, relative weight 0.7783), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.