Muscle wasting and atrophy, NEC, left upper arm

This code signifies a reduction in muscle mass and strength in the patient's left upper arm, not due to a specific neurological disease or disuse. It indicates a generalized or idiopathic muscle deterioration affecting this specific limb segment. This condition can lead to functional impairment and weakness.

Apply this code when documentation explicitly states muscle wasting or atrophy of the left upper arm without an underlying neurological cause (e.g., poliomyelitis, muscular dystrophy) or disuse atrophy. Common scenarios include idiopathic muscle loss, or atrophy secondary to conditions not specifically coded elsewhere that affect muscle integrity. Physician documentation must clearly specify "left upper arm" and rule out other specific causes.

• Ensure documentation specifies "left upper arm" to differentiate from other arm segments or laterality.
• Always look for an underlying cause; if a specific neurological condition or disuse is documented, a more specific code should be used.
• This code is for atrophy not elsewhere classified; if a more precise etiology is identified, select the code for that specific condition.