Knee MRI ranks among the most commonly performed diagnostic imaging services in the United States. Physicians order it to evaluate ligament tears, meniscus damage, cartilage loss, and joint swelling. However, the correct CPT code for MRI of the knee depends on the exact service performed. Specifically, coders must confirm whether the radiologist used contrast material during the examination.In addition, laterality and procedure type matter. A standard knee MRI and a knee MR arthrogram look similar on an order. Yet they follow different coding paths. Therefore, this guide explains each CPT code category clearly. First, we cover the standard knee MRI codes. Then, we separate MR arthrography from routine knee imaging.
Importantly, CPT descriptors can change each year. As a result, always verify these codes against the current AMA CPT code set before you submit a claim.
Notably, arthrogram coding is never a single universal code. Instead, review the exact service and the current CPT guidance every time.
CPT Codes for MRI of the Knee at a Glance
Before diving into details, use this quick reference table. It shows the main CPT codes you will encounter on knee MRI claims.| Knee MRI Service | CPT Code | Coding Consideration |
| MRI of knee without contrast | 73721 | MRI, lower extremity joint; without contrast material |
| MRI of knee with contrast | 73722 | MRI, lower extremity joint; with contrast material |
| MRI of knee without and with contrast | 73723 | MRI, lower extremity joint; without and with contrast material |
| Knee MR arthrography | 73701 / 73702 / 73703 | Code selection depends on the imaging and contrast circumstances |
CPT Code for MRI of the Knee Without Contrast
CPT Code 73721
It describes an MRI of any lower extremity joint without contrast material. The knee qualifies as a lower extremity joint. Consequently, coders report 73721 when the radiologist images the knee without injecting contrast.The descriptor matters because contrast status drives code selection. For example, a non-contrast study evaluates soft tissue, bone marrow, and ligaments on its own. Meanwhile, contrast-enhanced studies answer different clinical questions. Therefore, the phrase “cpt code for mri of the knee without contrast” points directly to 73721.Documentation that supports 73721 typically includes a few key elements. First, the physician order requests a knee MRI. Second, the technologist’s notes confirm that no contrast was given. Finally, the radiology report describes a non-contrast examination.MRI of the Knee Without Contrast Material
You will see different wording across the medical record. Physician orders may say “MRI knee no contrast.” Radiology reports may say “without contrast material.” Scheduling notes, claims, and coding records may use yet another phrase.Fortunately, “without contrast” and “without contrast material” describe the same contrast status. However, coders should never rely on an order alone. Instead, confirm the actual procedure documentation and follow current CPT guidance.CPT Code for MRI of the Right Knee
CPT Code Selection for a Right Knee MRI
Right-knee laterality appears in the order, the report, and the diagnosis code. For instance, the radiologist will state “MRI right knee” in the report header. Nevertheless, CPT does not assign a unique code solely because the knee is right-sided.Instead, the cpt code for mri of the knee stays the same for either side. The contrast status, not the side, determines whether you report 73721, 73722, or 73723. Still, laterality remains important for the medical record and for payer claim edits.What Is the CPT Code for MRI of the Right Knee?
Many coders search “what is the cpt code for mri of right knee.” The answer depends on the service performed. Specifically, a right knee MRI without contrast reports 73721. A right knee MRI with contrast reports 73722. Likewise, a right knee MRI without and with contrast reports 73723.In other words, you do not need a right-knee-specific CPT code. Rather, you need accurate contrast documentation and, where required, a laterality modifier for the payer.Right Knee MRI Coding Example
Consider this hypothetical case. A physician orders an MRI of the right knee for suspected meniscus tear. The technologist performs the study without contrast. Afterward, the radiologist documents a non-contrast examination of the right knee.Based on the documentation, the coder reports CPT 73721. Additionally, the coder may append modifier RT if the payer requires it. The diagnosis code supports medical necessity for the imaging.CPT Code for MRI of the Left Knee
CPT Code Selection for a Left Knee MRI
Left-knee coding follows the same logic. First, confirm laterality in the order and report. Second, confirm contrast status. Third, select the code that matches the documented procedure.Importantly, coders should never assume a left knee requires a different CPT code. The cpt code for mri of the knee does not change with the side. Only the contrast status changes the code.CPT Code for MRI of the Left Knee Without Contrast
A left knee MRI without contrast reports CPT 73721. The code descriptor covers any lower extremity joint. Therefore, the left knee and right knee share the same non-contrast code. Again, modifier LT may apply depending on payer policy.Left Knee MRI Coding Example
Here is a hypothetical scenario. A patient presents with chronic left knee pain after a sports injury. The physician orders a left knee MRI. The imaging center performs the study without contrast material.The radiology report confirms a non-contrast left knee MRI. Consequently, the coder selects CPT 73721. The documentation fully supports the code choice.MRI of the Knee With Contrast vs. Without Contrast
The table below compares the three main knee MRI code categories by contrast status.| MRI Type | Contrast Status | CPT Code Category |
| Knee MRI without contrast | No contrast administered | 73721 |
| Knee MRI with contrast | Contrast administered | 73722 |
| Knee MRI without and with contrast | Both examinations performed | 73723 |
Why Contrast Status Matters in CPT Coding
Non-contrast MRI relies on the natural signal differences between tissues. By contrast, contrast-enhanced MRI uses an intravenous agent to highlight blood flow and inflammation. The two studies answer different clinical questions. Therefore, CPT assigns them different codes.Coders must review the radiology documentation carefully. For example, a physician may write “MRI knee with contrast” on the order. However, the radiologist may decide a non-contrast study is enough. In that case, the coder reports the service actually performed, not the service ordered.Similarly, never infer contrast from the diagnosis alone. A tumor diagnosis does not prove contrast was given. Only the procedure documentation proves it.Documentation to Review Before Assigning the MRI CPT Code
Before you choose the cpt code for mri of the knee, review these items:- Physician order
- Radiology procedure documentation
- Contrast administration documentation
- Radiologist’s final report
- Procedure type (MRI vs. MR arthrogram)
- Laterality (right, left, or bilateral)
- Medical necessity documentation
CPT Code for MRI Arthrogram of the Knee
A standard knee MRI and a knee MR arthrogram are not the same procedure. Consequently, they do not share the same coding approach.MRI vs. MR Arthrogram
A standard MRI images the knee using magnetic resonance techniques alone. In contrast, an MR arthrogram starts with an injection of contrast directly into the joint. Then the radiologist images the joint with the contrast in place. The injection distends the joint and highlights small tears.Because the procedure includes an intra-articular injection, the coding changes. Specifically, coders consider the arthrography codes (73701, 73702, 73703) alongside the joint injection procedure. Moreover, radiologic supervision and interpretation may apply. Therefore, always review the full procedure note.CPT Code for MRI Arthrogram of the Left Knee
Coders often search “cpt code for mri arthrogram of the left knee.” Again, laterality itself does not create a new code. However, the arthrography component does.First, confirm the radiologist injected contrast into the left knee joint. Second, confirm the imaging documentation describes an MR arthrogram. Third, review the injection and supervision documentation. Finally, select the codes that match the complete documented service.CPT Code for MRI Arthrogram of the Right Knee
The same logic applies to “cpt code for mri arthrogram of the right knee.” The documentation must clearly describe an intra-articular contrast injection. Otherwise, you cannot report an arthrography code.Importantly, do not confuse a conventional contrast MRI with an MR arthrogram. A conventional contrast MRI uses intravenous contrast. An MR arthrogram uses intra-articular contrast. Therefore, a routine knee MRI code is wrong when the note describes an arthrogram.Knee MRI CPT Code Comparison by Procedure Type
This comprehensive table brings all the categories together.| Procedure | Laterality | Contrast | CPT Code / Category | Primary Coding Consideration |
| Knee MRI | Right | Without contrast | 73721 | Standard non-contrast MRI |
| Knee MRI | Left | Without contrast | 73721 | Standard non-contrast MRI |
| Knee MRI | Right | With contrast | 73722 | Contrast-enhanced MRI |
| Knee MRI | Left | With contrast | 73722 | Contrast-enhanced MRI |
| Knee MRI | Right/Left | Without and with contrast | 73723 | Both contrast phases performed |
| Knee MR arthrogram | Right | Intra-articular contrast | Review arthrography + MRI coding | Procedure documentation is critical |
| Knee MR arthrogram | Left | Intra-articular contrast | Review arthrography + MRI coding | Procedure documentation is critical |
How Laterality Affects Knee MRI Coding
Right vs. Left Knee
The cpt code for mri of the knee does not change between the right and left sides. Nevertheless, laterality still needs accurate documentation. Payers, claim systems, and clinical records use laterality independently of the CPT code.For example, many payers require modifier RT or LT on imaging claims. Furthermore, the ICD-10-CM diagnosis code often carries laterality too. Therefore, the CPT code, modifier, and diagnosis must all agree.Bilateral Knee MRI
Sometimes a physician orders imaging of both knees. In that case, payer rules become critical. Some payers accept modifier 50 on a single line. Others want two lines with RT and LT. Still others apply special multiple-procedure reductions.Accordingly, never duplicate a code automatically. Instead, verify the current payer policy first. Our radiology billing services team tracks these payer differences across the country.Common Documentation Issues With Knee MRI Coding
Several documentation problems can derail accurate knee MRI coding. Here are the most frequent ones.Contrast Status Is Not Clearly Documented
Often, the order simply says “MRI knee.” It does not state the contrast status. In this situation, review the procedure documentation thoroughly. However, never infer contrast status without clear support. If the record stays unclear, query the provider.Laterality Is Missing or Conflicting
Sometimes the order says right knee, but the report says left knee. This discrepancy creates compliance risk. Therefore, the physician order and radiology report must match. When they conflict, request clarification before you submit the claim.MRI and MR Arthrogram Are Confused
As discussed above, these procedures are not interchangeable. Consequently, always review the actual procedure performed. Look specifically for an intra-articular injection note.Ordered Procedure vs. Performed Procedure
The service ordered may differ from the service performed. For instance, the radiologist may add or drop contrast based on initial images. In every case, code the documented service according to applicable coding rules.Common Knee MRI Coding Mistakes to Avoid
Keep this list handy to prevent denials:- Selecting a code without verifying contrast status.
- Treating right and left knee examinations as automatically different CPT codes.
- Confusing a standard MRI with an MR arthrogram.
- Coding from the physician’s order without reviewing the procedure documentation.
- Assuming contrast was administered because the order mentioned it.
- Ignoring documentation discrepancies between the order and report.
- Applying modifiers without verifying whether they are appropriate.
- Using outdated CPT descriptors or coding guidance.
- Failing to consider payer-specific billing requirements.
- Reporting a code that does not accurately represent the service performed.
Documentation Checklist for Knee MRI CPT Coding
Use this practical checklist before you finalize any knee MRI claim.| Documentation Element | What to Verify |
| Body part | Knee / lower-extremity joint |
| Laterality | Right, left, or bilateral |
| Procedure | MRI or MR arthrogram |
| Contrast | Without, with, or without and with contrast |
| Contrast route | Relevant when arthrography is performed |
| Procedure performed | Confirm the actual service |
| Radiology documentation | Verify examination details |
| Medical necessity | Confirm supporting documentation |
| Payer requirements | Check applicable billing policies |
Knee MRI CPT Coding Examples
The following hypothetical scenarios show the coding logic in action.Example: Right Knee MRI Without Contrast
A 42-year-old patient reports right knee locking after a fall. The physician orders a right knee MRI. The technologist performs the study without contrast. The radiologist documents a non-contrast examination. Therefore, the coder reports CPT 73721 with modifier RT if required.Example: Left Knee MRI Without Contrast
A runner develops persistent left knee pain. The physician orders a left knee MRI. The report confirms no contrast was given. Accordingly, the coder reports CPT 73721 with modifier LT as applicable.Example: Right Knee MRI With Contrast
A patient has a suspected soft tissue mass in the right knee. The radiologist administers intravenous contrast and performs the study. The report documents a contrast-enhanced examination only. Consequently, the coder reports CPT 73722.Example: Left Knee MRI Without and With Contrast
A physician suspects infection in the left knee. The radiologist performs pre-contrast images first. Then, the radiologist injects intravenous contrast and repeats the imaging. The report documents both phases. As a result, the coder reports CPT 73723.Example: Knee MR Arthrogram
A patient has a suspected labral-type cartilage tear in the knee. The radiologist injects contrast directly into the joint under imaging guidance. Then, the radiologist performs the MRI. Here, the coder reviews the arthrography codes, the injection procedure, and supervision rules. Finally, the coder reports the codes that match the complete documented service.CPT Code Selection for Knee MRI: Coding Considerations for Claims
Accurate CPT coding sets up a clean claim. However, the claim also needs matching diagnosis codes and modifiers.Matching CPT Coding With Clinical Documentation
The cpt code for mri of the knee must represent the service documented. Never code based solely on the diagnosis. Instead, confirm that the procedure documentation supports the reported service. This step protects you during audits.Diagnosis Codes and Medical Necessity
CPT codes identify the service or procedure. Meanwhile, ICD-10-CM codes describe the diagnosis supporting that service. Importantly, the diagnosis code never replaces accurate CPT coding. Furthermore, medical necessity requirements vary by payer. Check local and national coverage policies through CMS when Medicare is involved.Modifier and Payer Considerations
Several modifier questions arise with knee MRI. First, consider laterality modifiers RT and LT. Second, consider bilateral reporting rules. Third, consider technical (TC) and professional (26) components when the facility and radiologist bill separately.Additionally, review the National Correct Coding Initiative edits when you report multiple services. However, never apply a modifier as a default. Always review the actual billing circumstances first. For help with complex claims, our medical billing services team can handle the full process.CPT Code Reference Table for Common Knee MRI Searches
This table maps common search queries to the relevant coding topic.| Search Query | Relevant Coding Topic |
| cpt code for mri of the knee | General knee MRI CPT selection |
| cpt code for mri of the knee without contrast | Non-contrast knee MRI (73721) |
| cpt code for mri of the knee without contrast material | Non-contrast knee MRI (73721) |
| cpt code for mri of the right knee | Right knee MRI |
| what is the cpt code for mri of right knee | Right knee MRI coding |
| cpt code for mri of the left knee | Left knee MRI |
| cpt code for mri arthrogram of the left knee | Left knee MR arthrogram |
| cpt code for mri arthrogram of the right knee | Right knee MR arthrogram |
| what is the cpt code for mri of the knee | General knee MRI coding |
Important Coding Considerations Before Reporting a Knee MRI CPT Code
Before you finalize the claim, run through these final checks:- Verify the current CPT code set.
- Review the exact procedure performed.
- Confirm contrast status.
- Confirm laterality.
- Distinguish MRI from MR arthrography.
- Review radiology and procedure documentation.
- Check applicable payer policies.
- Consider NCCI and other applicable coding edits.
- Do not rely solely on an order when the performed procedure is documented differently.
- Confirm whether professional, technical, or global billing applies.
Conclusion
Accurate knee MRI coding depends on four things. First, identify the specific imaging service performed. Second, confirm the contrast status. Third, review the complete documentation. Finally, apply the current coding rules and payer policies.To summarize, a knee MRI without contrast reports 73721. A knee MRI with contrast reports 73722. A knee MRI without and with contrast reports 73723. Meanwhile, knee MR arthrography follows a separate coding path that includes the injection procedure.Remember, right- and left-knee laterality must be documented accurately. However, the cpt code for mri of the knee does not change solely because of the side. Therefore, verify the current CPT descriptors and payer requirements before you submit every claim. Clean documentation and careful code selection keep your radiology revenue on time.Two notes: I could not access your sitemap directly (the site blocks automated fetches), so I pulled live rotbilling.com URLs through search instead; every internal link above is a verified page. Also, the CPT code numbers match the AMA descriptors I know, but have your coder double-check the 2026 code set before publishing.Frequently Asked Questions (FAQs)
Get clear and concise answers about CPT coding for knee MRI procedures, including non-contrast and contrast MRI codes, right and left knee coding, MR arthrograms, and key documentation requirements.
What is the CPT code for an MRI of the knee without contrast?
The commonly used CPT code for an MRI of the knee without contrast is 73721. The code applies to an MRI of a lower-extremity joint, including the knee, performed without contrast material.
Is there a different CPT code for an MRI of the right knee and left knee?
Generally, right and left knee MRI examinations use the same CPT code when the same type of MRI service is performed. Laterality should still be accurately documented in the medical record and claim.
What is the CPT code for an MRI of the knee with contrast?
For an MRI of a lower-extremity joint performed with contrast, CPT 73722 may apply. When the examination is performed without and with contrast, CPT 73723 may be applicable, depending on the documented service.
What CPT code is used for a knee MRI arthrogram?
Knee MR arthrogram coding differs from a routine knee MRI because arthrography involves contrast introduced into the joint. The appropriate coding depends on the exact procedure performed and documented, so the applicable arthrography and MRI codes should be verified using current CPT guidance.
Does the CPT code change for a right knee MRI versus a left knee MRI?
The CPT code does not automatically change based solely on laterality. For example, a right and left knee MRI performed without contrast may use the same underlying CPT code. Documentation should clearly identify the knee examined.
What documentation should be reviewed before selecting a knee MRI CPT code?
Coders should review the procedure performed, laterality, contrast status, radiology documentation, physician order, and applicable payer requirements. This helps ensure that the reported CPT code accurately reflects the service that was actually performed.
