CPT code 27598: Leg amputation, through knee joint2026 Medicare rate & RVUs in California

CMS doesn’t publish an office rate for 27598 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 27598 covers

At knee-disarticulation surgery, the surgeon separates the lower leg through the knee joint, leaving the femur intact. Orthopedic, vascular, or trauma surgeons may perform this operation for nonviable tissue from severe limb ischemia or infection, or for devastating injury, generally in an operating room. The operative report should establish the amputation level; a cut through the tibia below the knee or through the femur above the knee is a different level.

Report the service for the through-knee procedure and document the indication, operative level, and side. CMS assigns a 90-day global period, including the day-before preoperative visit and 90 days of related postoperative care. When multiple procedures occur in the same session, the highest-valued procedure is paid in full and the others at 50%. 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 27598 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 27598 rate is calculated

Each of 27598’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 27598

27598 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

27598 compared with similar codes

How to choose

27590Thigh amputationThrough femur, any level

Choose 27598 for disarticulation through the knee joint. Code 27590 describes an amputation through the femur.

27591Thigh amputationPrimary closure

Code 27591 is a femoral-level amputation with primary closure, not a through-knee amputation.

27592Thigh amputationImmediate prosthesis fitting

Code 27592 describes an open, circular amputation through the femur; 27598 is performed through the knee joint.

Codes related to 27598

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