Primary osteoarthritis, left ankle and foot

This code signifies degenerative joint disease affecting the left ankle and/or foot, where the osteoarthritis is not secondary to another condition like trauma or inflammatory arthritis. It involves the breakdown of cartilage in the joint, leading to pain, stiffness, and reduced mobility in the specified anatomical region.

Apply this code when documentation clearly indicates primary osteoarthritis affecting the left ankle or any joint within the left foot. This diagnosis is typically supported by imaging findings (e.g., X-rays showing joint space narrowing, osteophytes) and clinical symptoms consistent with degenerative changes, without an identifiable underlying cause.

• Ensure laterality is explicitly documented as "left" for the ankle and/or foot.
• Distinguish from secondary osteoarthritis (M19.1-) which requires an underlying cause.
• Code any associated pain (e.g., M79.672) separately if documented and not integral to the osteoarthritis diagnosis.