Anesthesia Coding Alert

Question: Our pain management specialist saw a patient with discomfort arising from carpal tunnel syndrome in both her hands. The physician administered therapeutic injections bilaterally into her wrists in the form of a corticosteroid along with a local anesthetic. What's the correct way to code for this procedure and diagnosis?

Illinois Subscriber

Answer: There are several elements to coding for this procedure. First, the best code for the injections your physician performed is 20526 (Injection, therapeutic [e.g., local anesthetic, corticosteroid], carpal tunnel).

Per the Medicare Physician Fee Schedule, you may report this code as a bilateral procedure with either modifier 50 (Bilateral procedure) or modifiers LT (Left side) and RT (Right side). For most payers that request you report the bilateral procedure with modifier 50, you'll append it to the injection code with one unit of service on a single line item. If your payer prefers modifiers LT and RT, report the injection code as two line items (one with LT and one with RT). Always check payer guidelines to be sure you're following their preferences.

Reminder: Be careful when coding for CTS. Many providers used to rely on either 20605 (Arthrocentesis, aspiration and/or injection; intermediate joint or bursa [e.g., temporomandibular, acromioclavicular, wrist, elbow or ankle, olecranon bursa]) or 64450 (Injection, anesthetic agent; other peripheral nerve or branch). However, CPT's introduction of 20526 several years ago provided you with a more accurate code in most circumstances.

Reimbursement bonus: If the pain management provider performs the injection in the office, many payers will reimburse separately for the cost of the drug used during the procedure -- a corticosteroid such as dexamethasone sodium phosphate or triamcinolone acetonide, for example.

Code for the dexamethasone using J1100 (Injection, dexamethasone sodium phosphate, 1 mg) or the triamcinolone using J3301 (Injection, triamcinolone acetonide, per 10 mg). Make sure that you accurately calculate the number of billable units based on the actual injection amount.

The diagnosis: ICD-9 includes only one CTS diagnosis: 354.0 (Carpal tunnel syndrome).

One last thing: Your physician should document not only the procedure but also the medical necessity for carpal tunnel injection to ensure reimbursement for CTS. With this in place, you can code compliantly for the pain management procedure. As with any procedure, check your carriers' specific policies to make sure you're meeting their requirements.