Billing code 27427: Knee reconstructionMedicare rate & RVUs in Illinois
Reports surgical reconstruction or augmentation of an extra-articular knee ligament when instability requires rebuilding structures outside the knee joint.
CMS doesn’t publish an office rate for 27427 in Illinois.
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 27427 covers
An orthopedic surgeon uses this service to rebuild or augment a ligament outside the knee joint, restoring stability when the ligament cannot be managed with a primary repair alone. The operation is typically performed in a hospital or ambulatory surgery center for traumatic or chronic knee instability; the operative report should identify the reconstructed ligament and establish that the work is extra-articular.
Choose this code for extra-articular reconstruction, not reconstruction within the joint or a combined intra- and extra-articular procedure. The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures are performed in the same session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% reduction. Bilateral reporting with modifier 50 is paid at 150%. An assistant at surgery may be paid; co-surgeons are paid only with supporting documentation, and team surgery is 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.
Where 27427 pays more and less in Illinois
The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.
| Payment locality | Office | Facility |
|---|---|---|
| Chicago | Unavailable | $747.20 |
| East St. Louis | Unavailable | $703.51 |
| Rest Of Illinois | Unavailable | $673.37 |
| Suburban Chicago | Unavailable | $720.72 |
How the 27427 rate is calculated
Each of 27427’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 · 27427
RVUs × geographic indexes × conversion factor
Swap in your local Medicare rate.
Work 9.55Practice expense 8.42Malpractice 1.87
All indexes start at 1.000 (the national rate). Enter a ZIP or drag a slider.
Payment rules and modifiers for 27427
27427 has a 90-day global period: related visits in that window are included in the surgery payment.
CMS payment indicators · 27427
Knee reconstruction
| 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) | 1 | Bilateral with modifier 50 pays 150% of the fee schedule amount. |
| Assistant at surgery (80/81/82/AS) | 2 | Paid. |
| Co-surgeons (62) | 1 | Permitted with supporting documentation. |
| 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 · 27427
Knee reconstruction
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 50 · payment effect
With and without the modifier
27427 without 50 · national facility
$662.67
Knee reconstruction
27427-50 · Bilateral: 150%
$994.01
Both sides on one line with modifier 50 are paid at 150% of the fee schedule amount (subject to multiple-procedure rules with other procedures).
27427 compared with similar codes
Compare codes
27427 vs 27428 vs 27429 vs 27405: national Medicare rates
Swap in your local Medicare rate.
How to choose
- 27428Knee reconstruction
- Use 27428 when the reconstructed ligament work is intra-articular. This code is for extra-articular reconstruction.
- 27429Knee reconstruction
- Use 27429 when the operation reconstructs both intra-articular and extra-articular structures; use this code for extra-articular reconstruction alone.
- 27405Knee ligament repair
- Code 27405 is for primary repair of a torn knee ligament. This code represents reconstruction or augmentation of an extra-articular ligament.
27427 billing questions
How is this distinguished from 27428 or 27429?
Use 27427 for reconstruction of an extra-articular ligament. Code 27428 describes intra-articular reconstruction, while 27429 represents work involving both locations.
What should the operative report document?
It should identify the ligament reconstructed, describe the reconstruction or augmentation performed, and make clear that the work was extra-articular.
Can this be reported with a primary ligament repair?
A reconstruction is distinct from primary repair. The record should support each separately reported service, and same-session multiple-procedure payment reduction may apply.
How is bilateral surgery reported?
For bilateral procedures, report modifier 50; CMS pays this code at 150% under the stated bilateral rule.
Can an assistant or co-surgeon be reported?
An assistant at surgery may be paid. Co-surgeon payment requires supporting documentation; team surgery is not permitted.
What care is included in the global period?
The 90-day global period includes the day-before preoperative visit and 90 days of related postoperative care.
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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