CPT code 27435: Knee capsulotomy, posterior release2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 27435 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 27435 covers

This procedure releases the posterior capsule of the knee through a surgical incision. An orthopedic surgeon may perform it for a fixed knee flexion contracture that restricts extension, often in a facility setting and sometimes as part of a broader operation for a stiff knee. The operative report should identify the posterior capsular release and the affected knee; a general description of knee exposure alone does not establish this service.

Report the code for the posterior release itself, not for an arthrotomy performed for another purpose, such as drainage or exploration. It has a 90-day global period that includes the day-before preoperative visit and related postoperative care during that period. 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-surgeon payment requires 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 27435 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 27435 rate is calculated

Each of 27435’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 27435

27435 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

27435 compared with similar codes

How to choose

27310Knee arthrotomyExploration, drainage, or foreign body

This code describes a knee arthrotomy for exploration, drainage, or foreign-body removal; 27435 is for posterior capsular release.

27425Patellar releaseOpen lateral retinacular release

This code releases the lateral retinaculum. Use 27435 for release of the posterior knee capsule, not a lateral patellar release.

27430QuadricepsplastyQuadriceps contracture release

Quadricepsplasty addresses restriction involving the quadriceps mechanism; 27435 releases the posterior capsule. Both require documentation when performed.

Codes related to 27435

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