Muscle wasting and atrophy, NEC, left lower leg

This code signifies a reduction in muscle mass and size in the left lower leg, not due to a specific neurological disease or disuse atrophy. It indicates a generalized or idiopathic muscle wasting affecting this specific anatomical region.

Apply this code when documentation specifies muscle atrophy or wasting in the left lower leg without an underlying neurological cause (e.g., poliomyelitis, muscular dystrophy) or direct disuse. Supporting documentation should clearly state the affected limb and rule out other specific etiologies.

• Ensure laterality is explicitly documented as "left lower leg" to support this specific code.
• Distinguish from disuse atrophy (M62.50-M62.59, fifth character 0 for unspecified) or atrophy due to specific neurological conditions (e.g., G71.0-G71.9).
• Always look for an underlying cause; if identified, code that primary condition first, and this code may be secondary.