Major osseous defects

This code represents significant structural deficiencies or loss of bone tissue within a skeletal site, often resulting from trauma, infection, tumor resection, or congenital anomalies. These defects are substantial enough to compromise the structural integrity and normal function of the affected bone.

Apply this code when documentation clearly indicates a large-scale loss of bone substance requiring complex reconstructive procedures or significantly impacting bone stability. This is typically supported by imaging reports (X-ray, CT, MRI) detailing the size and nature of the defect, as well as operative reports describing bone grafting or other reconstructive interventions.

• Differentiate from minor bone defects or non-union, which have separate codes.
• Always sequence this code after the underlying cause of the defect (e.g., fracture, osteomyelitis, tumor).
• Ensure the medical record explicitly describes the defect as "major" or provides measurements indicating a significant loss of bone.