Abnormal electromyogram [EMG]

This code indicates an abnormal finding on an electromyogram (EMG) of a limb or trunk muscle. An EMG measures the electrical activity of muscles in response to nerve stimulation, and an abnormal result suggests underlying neuromuscular dysfunction. This can include issues like nerve damage, muscle disease, or disorders affecting the neuromuscular junction.

This code is used when an EMG study of the limbs or trunk reveals findings outside of normal parameters, indicating a potential pathology. Documentation supporting its use would include the EMG report explicitly stating an abnormal finding, often with details about the specific abnormalities observed (e.g., fibrillation potentials, positive sharp waves, reduced amplitude). It is typically reported as a finding, not a definitive diagnosis.

• Always sequence this code after the definitive diagnosis or symptom that prompted the EMG, if known.
• Do not use this code if the EMG was performed on the eye; refer to the Excludes1 note.
• Ensure the documentation clearly states "abnormal" or provides specific findings that unequivocally indicate an abnormal result.