Coding and Billing With the New Neuromuscular Ultrasound CPT Code

On January 1, 2023, CPT released a new code specific to neuromuscular ultrasound (NMUS). This code, 76883, is used for reporting an ultrasound of a nerve(s) and accompanying structures throughout their entire anatomic course in one limb. The official CPT definition is 76883—Ultrasound, nerve(s) and accompanying structures throughout their entire anatomic course in one extremity, comprehensive, including real-time cine imaging with image documentation, per extremity. 
 
Comprehensive evaluation of a nerve is defined as evaluation of the nerve and its surrounding structures throughout its course in a limb.
 
In the upper limb, this would typically mean:

• Median nerve: proximal arm/axilla to the wrist
• Ulnar nerve: proximal arm/axilla to the wrist
• Radial Nerve: proximal arm/axilla to the elbow then following the posterior interosseous nerve to the extensor forearm and superficial radial sensory nerve to the wrist
• Musculocutaneous nerve: Proximal arm/axilla to the elbow and then following the lateral antebrachial nerve into the forearm

 
 In the lower limb:

• Sciatic nerve: gluteal fold to its division into the fibular and tibial nerves
• Fibular nerve: popliteal fossa to the fibular neck then following the superficial fibular to the ankle, and the deep fibular into the anterior compartment
• Tibial nerve: popliteal fossa to the ankle

 
Documentation of the entire course of a nerve throughout an extremity includes the acquisition and permanent archive of cine clips and static images to demonstrate the anatomy.
 
The new NMUS code was created because the only codes that were previously available for NMUS (76881 and 76882) were created with Radiology and Rheumatology as the primary users. The work described and reimbursed for these two codes often did not fit with the physician work required in more complex neuromuscular (NM) patients. The new code, 76883, is meant for use exclusively for more complex studies when an evaluation of a nerve(s) throughout its entire course takes place. Some common scenarios occur in situations like:
 

• Non-localized mononeuropathies
• Inflammatory demyelinating polyneuropathy (AIDP or CIDP)
• Multifocal motor neuropathy (MMN)
• Parsonage Turner syndrome
• Lesions within the nerve itself (ganglion cysts, tumors) etc. 

 
When using 76883, it can only be billed once per limb, even if an evaluation of more than one nerve takes place in that limb. The physician must save a cine as well as images, and document measurements as clinically indicated.  It is expected that this procedure will be performed by the physician as expert knowledge of anatomy and NM disease is needed to use ultrasound to differentiate conditions that previously would have often required an MRI. Overutilization of this code for less complex patients is a concern.
 
For more focal problems, such as carpal tunnel syndrome or ulnar nerve entrapment at the elbow, the two previously existing codes, 76881 (complete joint ultrasound) and 76882 (limited joint or focal evaluation of other non-vascular extremity structure ultrasound) are more appropriate. For example, when only measuring a cross sectional area of the median nerve at the wrist and forearm to diagnose CTS, the use of the limited code is more appropriate. If the physician is also making note of, documenting, and saving images of the joint space, peri-articular soft-tissue structures (muscles, tendons, and other soft tissue structures), and any identifiable abnormalities then the complete ultrasound code would be appropriate to use.
 
Examples of the 3 codes, and what should be imaged and reported in the medical record, are shown below.
 
Nonvascular extremity ultrasound - complete 76881
This code is used when a nerve is imaged at one or more sites and must include imaging of a complete joint (e.g., wrist joint for median nerve at the wrist; elbow joint for ulnar neuropathy at the elbow). Use of this code requires ultrasound examination of all the following joint elements: joint space (presence or absence of effusion, synovial hypertrophy, bony changes), peri-articular soft-tissue structures that surround the joint (muscles, tendons, and other soft-tissue structures), and any identifiable abnormality. Images of the nerve and surrounding joint should be saved to the permanent medical record.
 
Example report:
Ultrasound examination of the right elbow region was performed, with specific attention to the ulnar nerve. Representative images of pertinent findings were saved to the permanent medical record. A high-resolution portable ultrasound machine was used, with a 12-18 MHz linear transducer. The patient was positioned supine, with the elbow flexed to 90 degrees. Representative images and/or cines were saved to the permanent medical record.
 
There is significant enlargement of the right ulnar nerve (18 mm²; upper limit of normal for this lab is 10 mm²) at the cubital tunnel.
The elbow forearm ratio was > 2.5 (normal limit for this lab: <2).
No increase in vascularity was noted.
No intraneural or extraneural masses noted.
Dynamic maneuvers: No subluxation or dislocation of the ulnar nerve at the retrocondylar groove was noted.
No accessory muscles were present and there was no increase in echogenicity of ulnar innervated muscles in the forearm or hand.
Elbow joint: Normal joint space. No effusion or synovitis noted in the coronoid, radial or olecranon recesses. The medial epicondyle and olecranon were normal. The common flexor tendon was normal.
 
Nonvascular extremity ultrasound – limited 76882
This code is used for a limited evaluation of a joint or for a focal evaluation of a structure in an extremity other than a joint (such as a nerve at one or two sites), when there is not a complete description of a nearby joint. In the case of nerve, only the nerve needs to be assessed (e.g., measurement of cross-sectional areas or comment of echogenicity). Pertinent images with cross-sectional areas marked should be saved to the permanent medical record.
 
Example report:
The median nerve was imaged at the wrist and the forearm, to evaluate for swelling in the setting of carpal tunnel symptoms. A high-resolution portable ultrasound machine was used, with a 12-18 MHz linear transducer. The patient was positioned seated, with the forearm in relaxed supination. Representative images were saved to the permanent medical record.
 
The median nerve measured 14 mm² in cross-sectional area at the wrist (upper limit of normal for this lab > 12 mm²), and 5 mm² in the mid forearm. The wrist forearm ratio was increased at 2.8 (upper limit of normal for this lab: 2.0). These findings are consistent with the clinical diagnosis of carpal tunnel syndrome. 
 
Complex NMUS 76883
This code should be used when a physician uses ultrasound to perform a detailed examination of one or more of the major nerves in the upper or lower limb from near its origin through the entire course of the nerve. Note should be made of vascularity, cross-sectional area, mobility (including dynamic maneuvers in some cases), masses, accessory muscles, and echogenicity of innervated muscles. Save a short axis and long axis view of the area of interest. A cine in the area of interest as well as images of areas along the course of the nerve where measurements are made must be saved to the permanent medical record. 
 
Example case and ultrasound report:
In this case, a 36 y/o woman presents with numbness of digits 4 and 5, atrophy of the first dorsal interosseous and weakness of intrinsic hand muscles. NCS show reduced ulnar SNAP. CMAPs are consistent with axonal loss in the ulnar nerve with no focal slowing or conduction block at the elbow. Abnormalities on needle EMG (fibrillations and neurogenic units) are limited to FDI. The EDX impression is a non-localized axonal ulnar neuropathy. 
 
This is an appropriate case to image the ulnar nerve along its entire anatomic course. The ulnar SNAP is low, so it must be peripheral nerve, not root. If surgery is considered, it is important to identify the area of entrapment and although this is typically at the elbow, it can be at the wrist, distal forearm, or even upper arm. 
 
Ultrasound report:
Ultrasound examination of the right upper limb from the proximal humerus through to the hand was performed, with specific attention to the ulnar nerve. A high-resolution portable ultrasound machine was used, with a 12-18 MHz linear transducer. The patient was positioned supine, with the elbow flexed to 90 degrees. Representative images and cine were saved to the permanent medical record.
 
Ulnar nerve:
There is significant enlargement of the right ulnar nerve with decreased echogenicity, without increased vascularity, at the cubital tunnel (see measurements below - upper limit of normal for this lab 10 mm²).
The ulnar nerve in the axilla, proximal arm, mid forearm and at Guyon's canal was unremarkable.
No intraneural or extraneural masses were noted.
Dynamic maneuvers: No subluxation or dislocation of the ulnar nerve at the retrocondylar groove (see cine).
No accessory muscles noted, no increase in echogenicity of ulnar innervated muscles in the forearm or hand.
Optional: comment on the elbow joint (effusion or synovitis or any other findings)
 
Representative right ulnar nerve measurements (cross-sectional area):
Axilla: 7 mm²
Mid humerus: 6 mm²
Retrocondylar groove: 8 mm²
Cubital tunnel): 16 mm²
Mid forearm: 6 mm²
Wrist (Guyon's Canal): 5 mm²

Authors: Andrea Boon, MD and Carrie Winter, RHIA