Other osteonecrosis, other site

This code signifies osteonecrosis, also known as avascular necrosis, affecting a bone site not specifically classified elsewhere. It indicates the death of bone tissue due to a loss of blood supply, leading to bone collapse and potential joint destruction. This condition can be idiopathic or secondary to various factors like trauma, steroid use, or certain medical conditions.

Use this code when documentation clearly states osteonecrosis in a location not covered by more specific codes (e.g., hip, shoulder, knee, ankle, wrist, jaw). This applies to sites such as the tarsal bones (excluding ankle), metatarsals, phalanges of the foot or hand, or other unspecified bones. The medical record should explicitly state "osteonecrosis" or "avascular necrosis" and the affected "other site."

• Ensure the documentation specifies a bone site other than those with dedicated osteonecrosis codes.
• Do not use this code if a more specific anatomical site code for osteonecrosis is available (e.g., M87.0-M87.7 series).
• Always review the medical record for the underlying cause of osteonecrosis, as an additional code for the etiology may be required.