Below is from AMA CPT Changes 2002, at this time the code descriptor was muscle group(s) which was later changed to just muscle(s)
In the AMA coding examples they associate 3 separate muscles injected with 20553; whereas, if the documentation only lists 1-2 muscles then 20552 would reported.
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20552 single or multiple trigger point(s), one or two muscle group(s)
20553 single or multiple trigger point(s), three or more muscle groups
Clinical Example (20552)
A 60-year-old female with a three-month history of pain in the left low back above the left posterior iliac crest with radiation of pain into the left buttock. Muscle relaxants, nonsteroidal anti-inflammatory drugs, and physical therapy have been ineffective in relieving her pain. Physical examination reveals no evidence of neurological dysfunction, but does reveal a distinct trigger point in the multifidus muscle left of the L5 spinous process. She now presents for injection of the trigger point.
Clinical Example (20553)
A 40-year-old male presents with chronic left neck and right upper back pain resulting from cervical degenerative disk disease and myofascial pain syndrome. The patient has already completed a trial of physical therapy and nonsteroidal anti-inflammatory drug therapy without relief of his pain. Physical examination reveals no evidence of neurological dysfunction, but does reveal three distinct trigger points in the left multifidus muscle, the left trapezius muscle and the right levator scapular muscle. He presents for injection of the trigger points.
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Below is then from AMA CPT Changes 2003 where you can see the revised code descriptor referring to as muscle(s) instead of muscle group(s)
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20552 single or multiple trigger point(s), one or two muscle(s)
▲20553 single or multiple trigger point(s), three or more muscle(s)
"In order to allay confusion and assist in the choice of the most accurate code describing the procedure(s) performed, the code series 20550-20553 has been revised to indicate that codes 20552-20553 are reported one time per session, regardless of the number of injections or muscles injected. These changes were accomplished by appending an ?(s)? to the term ?Injection? and to the term ?muscle.?
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These codes then appeared in AMA CPT Changes 2004 with the below notation:
20550 Injection(s); single tendon sheath, or ligament, aponeurosis (eg, plantar ?fascia?)
▲20551 single tendon origin/insertion
▲20552 Injection(s); single or multiple trigger point(s), one or two muscle(s)
20553 single or multiple trigger point(s), three or more muscle(s)
(If imaging guidance is performed, see 76003, 76393, 76942)
Rationale
The injection codes 20550-20553 have been revised to clarify the intent of these codes, as related to multiple reporting of these services. In addition, the tendon injections and trigger point injections have been separated into two code families.
The tendon injection codes 20550 and 20551 are intended to be reported for multiple injections per single tendon sheath or ligament. Thus, multiple injections to the same tendon sheath or ligament would be reported only once per session, while injections to multiple tendon sheaths, tendon origins, tendon insertions, ligaments or aponeuroses would be reported for each injection. Code 20550 was also revised to include anatomical language in the descriptor.
The trigger point injection codes 20552 and 20553 are intended to be reported once per session, regardless of the number of trigger points or muscles injected.
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