Other secondary osteonecrosis, unspecified tibia

This code signifies osteonecrosis of the tibia that is not primary (idiopathic) and has an identifiable underlying cause, such as steroid use, trauma, or a systemic disease. The specific location within the tibia is not documented or is generalized. This condition involves the death of bone tissue due to a lack of blood supply, leading to pain, bone collapse, and joint dysfunction.

Use this code when documentation clearly indicates secondary osteonecrosis affecting the tibia, but the specific site (e.g., proximal, distal) is not specified. It is appropriate when the etiology is known (e.g., corticosteroid-induced, post-traumatic, sickle cell-related) but the exact tibial involvement is generalized or unstated. Supporting documentation should include imaging reports (MRI, X-ray) confirming osteonecrosis and clinical notes detailing the secondary cause.

• Always strive for greater specificity if the documentation allows, such as M87.361 for right tibia or M87.362 for left tibia.
• Ensure the documentation explicitly states "secondary" osteonecrosis and identifies the underlying cause, which should be coded first if it's the primary reason for the encounter.
• Differentiate from primary (idiopathic) osteonecrosis (M87.0-) and post-traumatic osteonecrosis (M87.1-) when the trauma is the direct cause, not just a contributing factor.