Billing code 20661: Cranial haloMedicare rate & RVUs in Nevada
Reports application of a four-pin cranial halo to stabilize the cervical spine, such as for selected fractures or instability requiring rigid immobilization.
CMS doesn’t publish an office rate for 20661 in Nevada.
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 9 sections
What 20661 covers
An orthopedic or neurosurgical provider applies a rigid ring secured to the skull with four pins to support cervical spine immobilization. The halo may be connected to a vest or another support as part of treatment for conditions such as a cervical fracture or instability. This service is generally performed in a hospital or other procedural setting when rigid external stabilization is needed.
Select this code for the four-pin cranial halo application; the six-or-more-pin application is reported with 20664. The application code includes removal of the halo. The record should support the clinical need for rigid stabilization and the pin configuration used. CMS assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. When other procedures are performed in the same session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% multiple-procedure reduction. Modifier 50 is inappropriate. Assistant-at-surgery payment is restricted, and co-surgeon and team-surgery billing are not permitted.
This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.
20661 in Nevada**
| Payment locality | Office | Facility |
|---|---|---|
| Nevada** | Unavailable | $543.96 |
How the 20661 rate is calculated
Each of 20661’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.
How the rate is built · 20661
RVUs × geographic indexes × conversion factor
Work5.13
5.13 RVUs× 1.000 GPCI
Practice expense9.68
9.68 RVUs× 1.000 GPCI
Malpractice1.76
1.76 RVUs× 1.000 GPCI
Adjusted RVUs
16.5700
Conversion factor
$33.4009
Medicare rate
$553.45
Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.
Payment rules and modifiers for 20661
20661 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 20661
Cranial halo
| Rule | CMS value | What it means |
|---|---|---|
| Global period | 090 | Major surgery: the day before, the day of, and 90 days after are included. |
| Multiple procedures | 2 | Standard reduction: highest-valued procedure at 100%, others at 50%. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 1 | Not paid (statutory restriction). |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 0 | Physician service: no professional/technical split. |
| Split (54/55/56) | 0.10/0.69/0.21 | Share of the payment for pre-op, the procedure itself, and post-op care. |
Global surgery period · 20661
Cranial halo
90-day global period ends
Dec 30, 2026
Covers Sep 30, 2026 through Dec 30, 2026 (92 days, including the day before surgery).
Visit on Oct 31, 2026
Day 30 of the 90-day post-op period: related follow-up care is included in the surgical payment.
Pre-op dayGlobal period
What modifiers do to the payment
Modifier 51 · payment effect
With and without the modifier
20661 without 51 · national facility
$553.45
Cranial halo
20661-51 · Second procedure: 50%
$276.73
When this isn’t the highest-valued procedure in the session, Medicare pays 50% of its fee schedule amount (the highest is paid at 100%).
20661 compared with similar codes
Compare codes · National
4 codes, side by side
How to choose
- 20664Cranial halo
- Both codes cover cranial halo application, but 20661 is for a four-pin configuration and 20664 is for six or more pins.
- 20660Cranial traction
- Use 20661 for a cranial halo; 20660 describes application of cranial tongs, calipers, or another traction device.
- 20665Cranial device removal
- Code 20661 covers halo application, including removal. Code 20665 describes removal of tongs or a halo previously applied by another physician.
20661 billing questions
When should 20661 be selected instead of 20664?
Use 20661 for application of a four-pin cranial halo. Code 20664 describes the six-or-more-pin cranial halo application.
Is halo removal separately reported after 20661?
Removal is included in the application service reported with 20661. Code 20665 is for removal of tongs or a halo previously applied by another physician.
Can modifier 50 be used for a halo applied on both sides?
No. CMS identifies bilateral adjustment as inappropriate for this code; the cranial halo application is not reported as a bilateral service.
What documentation supports reporting 20661?
Document the clinical reason for rigid cranial stabilization, the application performed, and the four-pin configuration. The record should distinguish this service from a halo using six or more pins.
How does the 90-day global period affect postoperative reporting?
The day-before preoperative visit and 90 days of related postoperative care are included in the global period. Other procedures performed in the same session are subject to the standard multiple-procedure payment reduction.
Can an assistant or co-surgeon be billed for this procedure?
Assistant-at-surgery payment is restricted for 20661. CMS does not permit co-surgeon or team-surgery billing for this code.
Where these rates come from
FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.
CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file lines behind this rate
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