CPT code 27424: Patella surgery, removal or revision2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 27424 in California.

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What 27424 covers

This code represents an operation to remove or revise the patella. Orthopedic surgeons typically perform it in a hospital or ambulatory surgical setting when the kneecap itself requires operative treatment, such as after significant damage or a prior patellar procedure. The operative report should make clear what was done to the patella and why; a procedure aimed at correcting patellar instability or resurfacing the patella is a different service.

Report 27424 for the patellar removal or revision actually performed, supported by the preoperative findings and operative details. CMS assigns a 90-day global period: the day-before preoperative visit and related postoperative care during the following 90 days are included. When multiple procedures occur in the same session, the highest-valued procedure is paid in full and other procedures are subject to the standard 50% reduction. For bilateral surgery, modifier 50 is paid at 150%. An assistant at surgery may be paid; co-surgeons require 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 27424 pays more and less in California

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

29 of 29 payment localities

How the 27424 rate is calculated

Each of 27424’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.

Payment rules and modifiers for 27424

27424 has a 90-day global period: related visits in that window are included in the surgery payment.

What modifiers do to the payment

When to use modifier 50

27424 compared with similar codes

How to choose

27420Patellar reconstructionWithout extensor realignment

Choose 27420 for reconstruction to address a dislocating patella. Choose 27424 when the operation removes or revises the patella itself.

27422Patellar reconstructionWith extensor realignment

Code 27422 describes instability reconstruction that includes extensor realignment or muscle advancement; 27424 describes removal or revision of the kneecap.

27437Patellar arthroplastyWithout prosthesis

Code 27437 is patellar arthroplasty without a prosthesis. It is not the code for removal or revision of the patella.

27438Patellar arthroplastyWith prosthesis

Code 27438 covers patellar arthroplasty with a prosthetic implant; 27424 covers removal or revision rather than implant-based resurfacing.

Codes related to 27424

Related codes aren’t interchangeable: bill the code that matches the service performed.

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

Open CMS sourceHow we calculate rates