M90.58

HCC Category Mapping

What This Code Means

Bone death (osteonecrosis) in other bone locations caused by another disease. The bone tissue dies as a secondary effect of an underlying condition in sites not covered by other specific codes.

Coding Tips

• •Use this code for osteonecrosis in unusual or multiple specific sites not captured by other M90.5x codes
• •Requires a secondary diagnosis code for the underlying disease causing the osteonecrosis

Clinical Significance

Secondary osteonecrosis at other anatomical sites represents bone death caused by an underlying classified disease affecting locations not covered by specific codes. This diagnosis requires specialized medical management and impacts risk adjustment modeling due to the complex nature of systemic disease-related bone necrosis.

Documentation Requirements

• ✓Clear documentation of underlying classified disease causing the osteonecrosis
• ✓Specific identification of anatomical site not covered by other M905 codes
• ✓Radiological evidence of bone necrosis (MRI, bone scan, or CT imaging)
• ✓Clinical correlation between primary disease and secondary bone death
• ✓Treatment plan addressing both underlying condition and osteonecrosis
• ✓Assessment of functional impact specific to the affected site
• ✓Provider statement confirming secondary rather than primary cause
• ✓Documentation excluding sites covered by other specific codes

Commonly Confused Codes