Idiopathic aseptic necrosis of left humerus

This code signifies the spontaneous death of bone tissue in the left upper arm bone (humerus) due to a lack of blood supply, without an identifiable cause such as trauma or infection. This condition, also known as avascular necrosis, leads to bone collapse and joint destruction over time.

Apply this code when documentation explicitly states idiopathic aseptic necrosis affecting the left humerus. This diagnosis is typically confirmed through imaging studies like MRI or X-ray, showing characteristic bone changes and ruling out secondary causes.

• Ensure laterality (left humerus) is clearly documented; separate codes exist for the right and bilateral involvement.
• Distinguish from secondary avascular necrosis, which would require an additional code for the underlying cause (e.g., steroid use, trauma).
• Do not confuse with osteomyelitis, which is an infection of the bone.