Neurology & Pain Management Coding Alert

Tip: Clarify MD's notation of CTS before coding.

When using ICD-9-CM, you currently have a single diagnosis choice for cubital tunnel syndrome: 354.2. Your options will expand and your provider's documentation will need to be more detailed when ICD-10 goes into effect Oct. 1, 2013, however.

ICD-10 options: Future codes for cubital tunnel syndrome will fall under G56, Mononeuropathies of upper limb. The classification excludes current traumatic nerve disorder, which you'll code as nerve injury according to the affected body region. The codes for cubital tunnel syndrome will be based on anatomic location:

• G56.20 -- Lesion of ulnar nerve, unspecified upper limb
• G56.21 -- Lesion of ulnar nerve, right upper limb
• G56.22 -- Lesion of ulnar nerve, left upper limb.

Other conditions in the same classification will include G56.0x (Carpal tunnel syndrome), G56.1x (Other lesions of median nerve), G56.3x (Lesion of radial nerve), G56.4x (Causalgia of upper limb), G56.8 (Other specified mononeuropathies of upper limb), and G56.9 (Unspecified mononeuropathy of upper limb).

Caution: If your physician only documents "CTS" in the patient record, verify whether you should code a diagnosis for cubital tunnel syndrome or carpal tunnel syndrome.

Differences: Cubital tunnel syndrome is a condition caused by increased pressure on the ulnar nerve at the elbow. The ulnar nerve passes under a bump of bone on the inner portion of the elbow and is susceptible to pressure because it lies directly next to the bone. Pressure on the nerve can disturb the way the nerve works and lead to numbness, tingling, and pain in the elbow, forearm, hand, and/or fingers.

The carpal tunnel is a narrow, rigid passageway of ligament and bones at the base of the hand. Carpal tunnel syndrome occurs when the median nerve running through this tunnel from the forearm into the hand becomes compressed at the wrist. The pressure can lead to pain, weakness, or numbness in the hand and wrist, radiating up the arm. Although painful sensations might indicate other conditions, carpal tunnel syndrome is the most common and widely known entrapment neuropathy involving compressed or traumatized peripheral nerves.

Being a common condition, however, doesn't mean a note of "CTS" on the patient's chart always means carpal tunnel syndrome. Checking the affected nerve and anatomic location will help you make the correct choice.