Certified Professional Coder (CPC) Quiz: Assign Injection Codes
20 questions · exam conditions
0:00
Assign Injection CodesQuestion 1 of 20

A physician injects corticosteroid into a single tendon sheath of the wrist for De Quervain tenosynovitis, without imaging guidance. Which CPT® code covers injection of a single tendon sheath?

20551
20550
20600
64450
← Back to quizzes

Certified Professional Coder (CPC) Quiz

Certified Professional Coder (CPC) Quiz: Assign Injection Codes

Practice Assign Injection Codes in Certified Professional Coder (CPC) with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Assign Injection Codes, giving you a quick way to practice the rules, question types, and explanations that matter most for Certified Professional Coder (CPC).

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

A physician injects corticosteroid into a single tendon sheath of the wrist for De Quervain tenosynovitis, without imaging guidance. Which CPT® code covers injection of a single tendon sheath?

  1. 20551
  2. 20550 (correct answer)
  3. 20600
  4. 64450
Explanation: CPT® 20550 covers injection(s), single tendon sheath, or ligament, aponeurosis — the correct code for a corticosteroid injection into a tendon sheath without imaging guidance. Code 20551 covers injection of tendon origin/insertion (enthesis), not the sheath itself; 20600 covers aspiration or injection of a small joint or bursa; 64450 covers peripheral nerve injection. When ultrasound guidance is separately documented, 76942 is additionally reported alongside 20550. Tendon sheath injections (20550) are anatomically distinct from joint injections (20600 series) and nerve blocks (64450).

Question 2

A physician performs a lumbar epidural steroid injection (interlaminar approach) at L4-L5 under fluoroscopic imaging guidance. Which CPT® code is reported for this injection?

  1. 62320
  2. 62321
  3. 62322
  4. 62323 (correct answer)
Explanation: CPT® 62323 covers injection of diagnostic or therapeutic substance into the lumbar or sacral epidural space with imaging guidance (fluoroscopy or CT). Imaging guidance is bundled into 62323 and is not separately reported. Code 62322 covers the same procedure without imaging guidance; 62320 covers cervical or thoracic epidural without imaging; 62321 covers cervical/thoracic epidural with imaging. When fluoroscopic guidance is documented for a lumbar epidural steroid injection, 62323 is the correct code.

Question 3

A physician performs trigger point injections into two separate muscle groups in the same session, without ultrasound guidance. Which CPT® code covers trigger point injection of 1 or 2 muscle groups?

  1. 20550
  2. 20552 (correct answer)
  3. 20551
  4. 20553
Explanation: CPT® 20552 covers injection(s), single or multiple trigger point(s), 1 or 2 muscle groups. Code 20553 covers trigger point injections into 3 or more muscle groups; 20550 covers injection of a tendon sheath, ligament, or aponeurosis; 20551 covers injection of single tendon origin/insertion. The number of muscle groups — not the number of individual trigger points — determines code selection. When ultrasound guidance is used, 76942 is separately reported alongside 20552 or 20553.

Question 4

A nurse administers a single intramuscular (IM) injection of a non-chemotherapy therapeutic drug (e.g., an antibiotic) in the physician's office. Which CPT® code covers this IM injection?

  1. 96365
  2. 96374
  3. 96372 (correct answer)
  4. 96402
Explanation: CPT® 96372 covers therapeutic, prophylactic, or diagnostic injection, subcutaneous or intramuscular. Code 96365 covers intravenous infusion; 96374 covers IV push injection; 96402 covers chemotherapy injection into subcutaneous or intramuscular tissue. For a standard IM injection of a non-chemotherapy drug, 96372 is the correct code. Route of administration (IM/SC vs. IV) determines the injection code selection.

Question 5

A physician injects a large joint (knee) with corticosteroid and a local anesthetic for pain management. Which CPT® code covers injection of a major joint without ultrasound guidance?

  1. 20610 (correct answer)
  2. 20605
  3. 20600
  4. 20611
Explanation: CPT® 20610 covers arthrocentesis, aspiration and/or injection of major joint or bursa (e.g., shoulder, hip, knee, subacromial bursa) without ultrasound guidance. Code 20605 covers an intermediate joint (e.g., temporomandibular, acromioclavicular); 20600 covers a small joint; 20611 covers major joint injection with ultrasound guidance and permanent record. The knee is a major joint, making 20610 the correct code for an injection without imaging guidance.

Question 6

A patient receives two different drugs sequentially by IV push during the same encounter. After the first drug is given and the line is flushed, a second, different drug is given by IV push. Which CPT® code covers each additional sequential IV push of a new substance?

  1. 96375 (correct answer)
  2. 96374
  3. 96376
  4. 96377
Explanation: CPT® 96375 covers each additional sequential IV push of a new substance or drug during the same encounter. Code 96374 is reported for the initial IV push of the session; 96376 covers re-dosing of the same substance by IV push; 96377 is for home infusion IV push services. When a second, different drug is given by IV push after the initial push, 96375 is the correct add-on code. The key distinction is a new substance (96375) versus re-dosing the same substance (96376).

Question 7

A patient receives an intravenous infusion of normal saline for hydration lasting 45 minutes. Which CPT® code covers intravenous hydration, initial, 31 minutes to 1 hour?

  1. 96360 (correct answer)
  2. 96361
  3. 96365
  4. 96366
Explanation: CPT® 96360 covers intravenous infusion, hydration, initial, 31 minutes to 1 hour. Add-on code 96361 covers each additional hour of hydration beyond the first. Code 96365 covers initial therapeutic drug infusion (not plain hydration); 96366 covers each additional hour of therapeutic drug infusion. Hydration codes (96360-96361) are used when only fluid without a therapeutic drug is administered and apply specifically to infusions lasting at least 31 minutes.

Question 8

A physician performs a median nerve block at the wrist for carpal tunnel pain management. Which CPT® code covers injection of anesthetic into a peripheral nerve when no more specific named nerve code exists?

  1. 64400
  2. 64415
  3. 64450 (correct answer)
  4. 64455
Explanation: CPT® 64450 covers injection(s), anesthetic agent(s) and/or steroid, other peripheral nerve or branch — the appropriate code for the median nerve at the wrist, which has no dedicated CPT® code. Code 64400 covers the trigeminal nerve; 64415 covers brachial plexus injection; 64455 covers plantar common digital nerve. When a named peripheral nerve is injected but lacks its own dedicated CPT® code, 64450 is the correct non-specific peripheral nerve injection code.

Question 9

A patient with allergic rhinitis receives 2 subcutaneous allergen immunotherapy injections in the physician's office. The physician did not prepare the antigens — they were provided by another allergist. Which CPT® code covers professional services for allergen immunotherapy, 2 or more injections, not including provision of antigens?

  1. 95115
  2. 95117 (correct answer)
  3. 95120
  4. 95165
Explanation: CPT® 95117 covers professional services for allergen immunotherapy, 2 or more injections, not including provision of antigens. Code 95115 covers a single injection without antigen provision; 95120 covers a single injection including antigen preparation and provision; 95165 covers professional services for antigen preparation only. When the physician provides only the injection service (not the antigens), 95117 is reported for 2 or more injections and 95115 for a single injection.

Question 10

A physician performs a sacroiliac (SI) joint injection under fluoroscopic guidance for sacroiliac joint dysfunction. Which CPT® code is specific to sacroiliac joint injection with image guidance?

  1. 27096 (correct answer)
  2. 64490
  3. 64493
  4. 20610
Explanation: CPT® 27096 covers injection procedure for sacroiliac joint, anesthetic/steroid, with image guidance (fluoroscopy or CT) — found in the musculoskeletal surgery section. Code 64490 covers cervical or thoracic facet joint injection; 64493 covers lumbar or sacral facet joint injection; 20610 covers major joint injection without imaging guidance. The sacroiliac joint injection has a dedicated code (27096) that is distinct from both facet joint codes and the general joint injection codes.

Question 11

A patient is receiving an IV infusion of drug A when drug B — a different substance — is administered as an additional IV push during the same session. Which CPT® code covers each additional sequential IV push of a new substance during an ongoing encounter?

  1. 96375 (correct answer)
  2. 96374
  3. 96376
  4. 96377
Explanation: CPT® 96375 covers each additional sequential IV push of a new substance or drug during the same encounter. Code 96374 is reported for the initial IV push of the session; 96376 covers each additional sequential push of the same substance (re-dose); 96377 is for home infusion IV push services. When drug B (a new substance) is pushed during an encounter where another service is already being provided, 96375 is the correct add-on code. The key distinction: new substance = 96375; same substance re-dosed = 96376.

Question 12

A patient receives IV normal saline hydration for 60 minutes, followed sequentially by a 45-minute IV infusion of a therapeutic antibiotic during the same encounter. Per CPT® drug administration hierarchy, which statement correctly describes how these services are reported?

  1. 96360 and 96365 are each reported as separate initial infusion services for the same encounter
  2. 96365 is the primary service per hierarchy; the hydration meeting the minimum time threshold may be additionally reported (correct answer)
  3. 96360 is the primary service because hydration was initiated first; 96367 covers the sequential antibiotic infusion
  4. 96368 is used because a second substance was administered during the same infusion encounter
Explanation: Per CPT® drug administration hierarchy, therapeutic/prophylactic drug infusions (96365 series) always outrank hydration infusions (96360 series) as the primary service, regardless of which was initiated first. Two initial codes cannot both be reported for the same encounter — the highest-hierarchy service defines the primary code. 96365 is therefore the primary service for the antibiotic infusion. The hydration meeting the minimum time threshold (≥31 minutes) may be additionally reportable per hierarchy rules. Code 96367 covers sequential infusion of a new substance when a drug infusion is already primary; 96368 covers concurrent (simultaneously running) additional drug infusion — neither applies to this hierarchy determination.

Question 13

A physician performs a celiac plexus nerve block using a neurolytic substance for management of intractable pancreatic cancer pain. Which CPT® code covers neurolytic agent injection into the celiac plexus?

  1. 64505
  2. 64520
  3. 64530 (correct answer)
  4. 64600
Explanation: CPT® 64530 covers injection(s), anesthetic agent(s) and/or neurolytic agent, celiac plexus, with or without radiologic monitoring. Code 64505 covers sphenopalatine ganglion; 64520 covers lumbar or thoracic (paraspinal sympathetic) nerve; 64600 covers destruction of the trigeminal nerve. The celiac plexus has its own designated code (64530). Neurolytic celiac plexus block is among the most commonly tested sympathetic nerve injection codes for the CPC exam.

Question 14

A pain management physician performs a lumbar facet joint injection at L3–L4 (single level) under fluoroscopic guidance. Which CPT® code covers lumbar or sacral paravertebral facet joint injection, single level?

  1. 64490
  2. 64495
  3. 64496
  4. 64493 (correct answer)
Explanation: CPT® 64493 covers injection(s) of anesthetic and/or steroid into a paravertebral facet joint or facet joint nerve, lumbar or sacral, single level. Add-on code 64494 covers each additional lumbar or sacral level; 64490 covers cervical or thoracic single-level facet injection; 64495 covers each additional cervical or thoracic level. Fluoroscopic guidance is bundled into these codes and is not separately reported. For a single lumbar level (L3–L4) facet joint injection, 64493 is correct.

Question 15

A patient receives an intra-articular injection of the right hip. The procedure note documents no imaging guidance was used. Which CPT® code covers injection of a major joint without ultrasound guidance?

  1. 20610 (correct answer)
  2. 20611
  3. 20605
  4. 20600
Explanation: CPT® 20610 covers arthrocentesis, aspiration and/or injection of major joint or bursa, without ultrasound guidance. The hip is a major joint along with the shoulder, knee, and subacromial bursa. Code 20611 adds ultrasound guidance with permanent recording; 20605 covers intermediate joints; 20600 covers small joints. When a major joint injection is performed without ultrasound guidance, 20610 is correct. Fluoroscopic guidance (if used) is separately reported with 77002; only ultrasound guidance changes the base joint injection code.

Question 16

A patient receives an intra-articular injection of the left shoulder under ultrasound guidance, with permanent image documentation. Which CPT® code covers major joint injection with ultrasound guidance?

  1. 20600
  2. 20604
  3. 20610
  4. 20611 (correct answer)
Explanation: CPT® 20611 covers arthrocentesis, aspiration and/or injection of a major joint or bursa with ultrasound guidance and permanent recording and reporting. Code 20610 covers major joint injection without ultrasound guidance; 20600 covers small joint without guidance; 20604 covers small joint with ultrasound guidance. When ultrasound guidance is used and a permanent record is documented, the with-guidance code (20611 for major joint) must be reported instead of 20610.

Question 17

A patient receives a 2-hour IV infusion of a first chemotherapy drug, followed immediately by a 1-hour IV infusion of a second, different chemotherapy drug (sequential administration). Which CPT® code covers sequential infusion of an additional chemotherapy drug?

  1. 96413
  2. 96415
  3. 96416
  4. 96417 (correct answer)
Explanation: CPT® 96417 covers sequential infusion of an additional chemotherapy drug or substance administered after the completion of the first agent. Code 96416 covers concurrent infusion — when a second drug runs simultaneously alongside the primary infusion. Code 96413 covers initial chemotherapy infusion up to 1 hour; 96415 covers each additional hour for the same drug. Because the second drug is administered after the first is complete (sequential), 96417 is the correct add-on code.

Question 18

A patient develops a severe post-dural puncture headache following a spinal anesthetic. The anesthesiologist performs an epidural blood patch to seal the dural leak. Which CPT® code covers the epidural blood patch?

  1. 62270
  2. 62272
  3. 62273 (correct answer)
  4. 62280
Explanation: CPT® 62273 covers injection of blood or clot patch, epidural — the standard code for an epidural blood patch used to treat post-dural puncture headache (PDPH). Code 62270 covers spinal puncture for diagnostic purposes; 62272 covers therapeutic spinal puncture with drainage of cerebrospinal fluid; 62280 covers injection of a neurolytic substance into the subarachnoid space. The epidural blood patch (62273) is a distinct, separately reportable procedure from diagnostic or drainage punctures.

Question 19

A patient receives a single IV push injection of ondansetron (Zofran) for nausea. No infusion is administered during this encounter. Which CPT® code covers a single IV push injection?

  1. 96365
  2. 96366
  3. 96374 (correct answer)
  4. 96375
Explanation: CPT® 96374 covers therapeutic, prophylactic, or diagnostic injection, IV push, single or initial substance. Code 96365 covers IV infusion (initial, up to 1 hour); 96366 covers each additional hour of IV infusion; 96375 covers sequential IV push of a new substance. A single IV push injection — administered rapidly over less than 15 minutes — is specifically coded with 96374. IV push and IV infusion have distinct codes based on the rate and duration of administration.

Question 20

A patient receives an IV infusion of a therapeutic antibiotic for 90 minutes. Which CPT® codes are reported for this infusion?

  1. 96365
  2. 96365, 96366 (correct answer)
  3. 96366
  4. 96368
Explanation: CPT® 96365 covers initial IV infusion, up to 1 hour. Add-on code 96366 covers each additional hour beyond the first (minimum 30 additional minutes to qualify). For a 90-minute infusion: 96365 for the first hour and 96366 for the additional 30 minutes — both codes are reported. Code 96366 alone is never correct since it is an add-on code requiring 96365 as the primary. Code 96368 covers concurrent infusion of a second drug during a primary infusion and does not apply here.