MRI of a hip, knee, or ankle joint done first without contrast and then with IV contrast, used for infection, tumor, inflammatory arthritis, or complex postoperative cases.
- Medicare
- $381.44
- Work RVU
- 2.1
- Global, days
- Region
- Multi-region
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 3 cited references ↓
- Specific reason contrast is needed (infection, mass, synovitis, postoperative evaluation)
- Both non-contrast and contrast phases described in the report
- Contrast agent and dose
- Joint and laterality
- Authorization matching 73723
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 3 cited references ↓
73723 is the dual-phase lower extremity joint MRI: a non-contrast series, then a post-contrast series after IV gadolinium. It is not the routine knee MRI. That is 73721. Ortho ordering for 73723 is usually about septic arthritis, osteomyelitis near a joint, a mass, synovitis, or a painful joint replacement where the surgeon wants to see enhancement.
Both phases must be documented and read. If contrast was held because of kidney function or an allergy, recode to 73721. If only post-contrast images were acquired, code 73722.
Denials for 73723 often come down to medical necessity. A diagnosis of knee pain or meniscal tear does not explain why contrast is needed, and radiology benefit managers will push back or downgrade the authorization to 73721. The ordering note should state the specific concern that contrast answers. Bill laterality, and split 26 and TC when the read and the scanner belong to different entities.
RVU & reimbursement
Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.
Source · CMS Physician Fee Schedule, RVU26A · January 2026
Work RVU vs. total RVU
The work RVU (2.1) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (11.42) adds practice overhead and malpractice, and is what drives the Medicare payment below.
| Work RVU | 2.1 |
| Practice expense RVU | 9.17 |
| Malpractice RVU | 0.15 |
| Total RVU | 11.42 |
| Medicare national rate | $381.44 |
| Global period | days |
Payment by site of service
Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.
Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026
| Setting | Medicare rate (national) |
|---|---|
Office (PFS non-facility) Procedure performed in physician's office | $381.44 |
HOPD (APC 5572) Hospital outpatient department | $356.43 |
Common denial reasons
The recurring reasons claims for CPT 73723 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Authorization approved only for 73721
- Diagnosis is routine internal derangement with no reason for contrast
- Contrast not actually administered
- Missing laterality
- Both 26 and global billed for the same study
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 3 cited references ↓
01What is the difference between 73721 and 73723?
02Why was my 73723 authorization downgraded to 73721?
03What if contrast was ordered but not given?
Sources & references
Editorial content was developed using the following public sources.
Mira Scribe
Mira Scribe notes capture the specific clinical concern, such as possible infection around a replacement, that makes a contrast joint MRI medically necessary.
See how Mira captures CPT 73723 documentation