Idiopathic aseptic necrosis of unspecified hand

This code signifies the death of bone tissue in an unspecified hand due to a lack of blood supply, without an identifiable cause (idiopathic) and without evidence of infection (aseptic). This condition, also known as osteonecrosis or avascular necrosis, leads to bone collapse and joint destruction.

Apply this code when documentation clearly states idiopathic aseptic necrosis affecting any bone within the hand, and the specific hand (left or right) is not specified. This diagnosis is typically supported by imaging studies (e.g., X-ray, MRI) showing characteristic bone changes and a clinical history ruling out trauma, steroid use, or other known causes of osteonecrosis.

• Ensure the documentation explicitly states "idiopathic" and "aseptic" to differentiate from other forms of osteonecrosis.
• If the specific hand is known (left or right), use the more specific codes (M87.041 or M87.042).
• Do not use this code if the necrosis is due to trauma, drug-induced, or other specified causes; instead, refer to the appropriate M87 subcategories.