Other chronic osteomyelitis, left radius and ulna

This code signifies a persistent, long-standing infection of the bone and bone marrow affecting both the radius and ulna in the patient's left forearm. It indicates a non-acute inflammatory process, often characterized by recurrent symptoms, bone destruction, and the presence of sequestra or involucrum.

Apply this code when documentation explicitly states "chronic osteomyelitis" involving the left radius and ulna, and specifies that it is not a Brodie's abscess, post-traumatic, or due to other specified causes. Supporting documentation would include imaging reports (X-ray, MRI, CT) showing chronic bone changes, pathology reports confirming chronic inflammation, and physician notes detailing the long-term nature of the infection.

• Differentiate from acute osteomyelitis (M86.0-) and subacute osteomyelitis (M86.1-).
• Ensure laterality (left) is clearly documented for both radius and ulna.
• If the osteomyelitis is post-traumatic, use codes from category M86.3- or M86.4- instead.