Anesthesia Coding Alert

Question: What codes should we submit for an obturator nerve block and obturator muscle injection?

Connecticut Subscriber

Answer: The obturator nerve is a somatic nerve, so report a local anesthetic injection with 64450 (Injection, anesthetic agent; other peripheral nerve or branch). If your neurologist documents that he injected trigger points in the obturator muscles separate from the injection location for the obturator nerve injection, then you should also look at code 20552 (Injection[s]; single or multiple trigger point[s], 1 or 2 muscle[s]).

Anatomy: The obturator nerve originates from the second, third, and fourth lumbar nerves. The obturator innervates the adductor, gracilis, and obturator externus muscles, plus the skin of the medial aspect of the thigh, hip, and knee joints. The obturator externus and obturator internus muscles cover parts of the pelvic area. Coding for an obturator muscle injection depends first and foremost on whether the injection is separate and distinct from the obturator nerve injection.