Kaiser Permanente Total Knee Arthroplasty Coverage

Coverage and Medical Necessity Criteria

Inpatient Level-of-Care Criteria (Elective TKA/TKR)

For elective total knee replacement or revision to be approved as inpatient, ONE of the following must be met:

Inpatient indications: 1. Bilateral knee replacement; 2. Coexisting neurologic condition (such as multiple sclerosis, hemiparesis, severe Parkinson's, or other neurologic conditions) where the expected length of stay is planned to be longer than 2 midnights; OR 3. Meets indications on the Elective Surgical Procedure Level of Care policy.

Medical Necessity Criteria for Elective Total/Partial Knee Arthroplasty (non-Medicare requests / general)

Total and unicompartmental knee arthroplasty may be considered medically necessary when ALL of the following are met:

Core requirements: 1) Functional disabling pain of at least 3 months duration that interferes with activities of daily living; 2) Radiographic or arthroscopic evidence of moderate–severe osteoarthritis (Kellgren-Lawrence grade 3–4 or Outerbridge grade IV); 3) At least 3 months of non-operative conservative treatment (eg, NSAIDs, acetaminophen, and intra-articular corticosteroid injection as appropriate); 4) Trial of Physical Therapy in the last 12 months (supervised PT with attendance >75% of sessions and documented flexibility/strengthening exercises and activity modification) or documentation why PT is not appropriate; 5) Optimization criteria met (BMI, glycemic control, and tobacco/nicotine use) as described below.

Kaiser Permanente National Criteria (effective Oct 1, 2026)

Total and/or partial knee arthroplasty may be considered medically necessary when ALL the following are met:

National criteria specifics (effective Oct 1, 2026): 1) Functional disabling pain ≥3 months interfering with activities of daily living; 2) Radiographic/arthroscopic evidence of moderate–severe OA (K-L grade 3–4 or Outerbridge grade IV); 3) At least 3 months of conservative medication therapy (NSAIDs, acetaminophen, or intra-articular corticosteroid as appropriate); 4) Trial of at least 3 Physical Therapy sessions in the last 12 months with documentation of flexibility/muscle strengthening exercises and activity restriction OR documentation that PT is not clinically appropriate due to severe pain or limitations; 5) BMI < 40, with documented optimization efforts if BMI > 40 (sustained attempts at weight loss over 3–6 months or documented participation in a weight loss/exercise program with formal nutritional counseling); 6) If diabetic, HbA1c < 7.5 (or <8.0 with comorbid heart disease) and active medical management with documented improvement efforts if not at target; 7) Tobacco/nicotine users must be engaged in a cessation program and be tobacco-free for ≥30 days prior to surgery or demonstrate a 90% reduction in use, with shared decision making and case review if optimization not achieved.

Other accepted indications

Knee arthroplasty may ALSO be considered medically necessary after failure of nonoperative interventions for any of the following:

Additional indications: Distal femur fracture in a patient with osteoporosis; Failure of a previous proximal tibial or distal femoral osteotomy; Hemophilic arthropathy; Limb salvage for malignancy; Post‑traumatic knee joint destruction; Avascular necrosis of the tibial or femoral condyle; Inflammatory arthritis.

Medically Necessary – Total Knee

Considered medically necessary when criteria in the applicable policy statements are met

Medically necessary TKA: Procedure is considered medically necessary when the applicable policy criteria are met for the patient and the requested CPT/HCPCS code(s).

Refer to the full policy statements for detailed clinical criteria, coding, and documentation requirements.

Exclusions that contraindicate knee arthroplasty include active joint infection or systemic bacteremia, an active skin infection within the planned surgical approach, and unstable angina. Additionally, any medical condition that would interfere with successful rehabilitation or patients who are non‑ambulatory at baseline are listed as exclusions.

When considering arthroplasty for malignancy, the policy notes that use of TKR must weigh life expectancy and alternative procedures; malignancy is an accepted indication only after individualized consideration. The policy also cautions that deleted or inactive CPT codes and codes that are not in effect at the time of service may not be covered, and directs providers to verify authorization requirements by plan using the pre‑authorization code check.

Any procedure attempted or planned in the presence of the exclusion conditions listed (for example, active joint or systemic infection, active skin infection in the surgical field, unstable angina, conditions that preclude rehabilitation, or baseline non‑ambulation) is considered not medically necessary / contraindicated by this policy.

The excerpt does not provide a separate explicit list labeled “not medically necessary” beyond the stated exclusions; however, prior authorization or claims may be denied for reasons including insufficient documentation (for example, failure to submit the last 6 months of clinical notes including history & physical) or use of deleted/inactive CPT codes that are not in effect at the time of service.

Procedure Codes and Thresholds

Procedure CPT codes referencedCPT

27438	Removal of prosthesis, knee; with insertion of new prosthesis (Total knee arthroplasty) (listed in document)
27446	Arthroplasty, knee, condyle and plateau; medial OR lateral compartment.
27447	Arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing (total knee arthroplasty).
27486	Revision of total knee arthroplasty, with or without allograft; 1 component.
27487	Revision of total knee arthroplasty, with or without allograft; femoral and entire tibial component.
27488	Removal of prosthesis, including total knee prosthesis, methylmethacrylate with or without insertion of spacer, knee.

Considered Medically Necessary CPT/HCPCS CodesCPTCovered

27437	Arthroplasty, patella; without prosthesis.
27438	Arthroplasty, patella; with prosthesis.
27440	Arthroplasty, knee, tibial plateau;
27441	Arthroplasty, knee, tibial plateau; with debridement and partial synovectomy.
27442	Arthroplasty, femoral condyles or tibial plateau(s), knee;
27443	Arthroplasty, femoral condyles or tibial plateau(s), knee; with debridement and partial synovectomy.
27445	Arthroplasty, knee, hinge prosthesis (eg, Walldius type).
27446	Arthroplasty, knee, condyle and plateau; medial OR lateral compartment.
27447	Arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing (total knee arthroplasty).
27486	Revision of total knee arthroplasty, with or without allograft; 1 component.

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BMI threshold — current and future (national) thresholds and optimization notes

Current BMI thresholdBMI < 35 required; if BMI > 35, document optimization efforts (sustained weight loss over 3–6 months or participation in weight loss/exercise program) and formal nutritional counseling; shared decision making allowed if optimization unsuccessful

Planned national BMI threshold (effective Oct 1, 2026)BMI < 40 required; if BMI > 40, optimization efforts must be documented (sustained weight loss over 3–6 months or documented participation in weight loss/exercise program) and formal nutritional counseling

Relative contraindication levelsBMI > 40 is a relative contraindication; cases with inadequate BMI may be reviewed case-by-case by a medical director if adequate optimization efforts are documented

Optimization documentation requiredDocument active attempts toward weight loss (sustained weight loss or stagnant weights despite active participation), plus formal nutritional counseling; record shared decision making discussion if proceeding without target BMI

Prior Authorization, Documentation, and Conservative Therapy Requirements

Prior Authorization

Prior Authorization Required

Prior Authorization Required: Prior authorization is required for total knee arthroplasty (including total, partial/uni-compartmental, patellar arthroplasty, and revision codes). Inpatient requests must demonstrate level-of-care criteria and fulfillment of medical necessity prerequisites; ambulatory/outpatient requests must meet the Medical Necessity Criteria. If the orthopedist believes inpatient level is appropriate despite not meeting standard criteria, a case-by-case explanation may be submitted for review.

Applies to CPT codes including, but not limited to: 27437, 27438, 27440, 27441, 27442, 27443, 27445, 27446, 27447, 27486, 27487, 27488
Use Pre-authorization Code Check to verify plan-specific requirements

Step Therapy

Conservative Therapy Requirements

Conservative therapy prerequisites must be documented prior to approval unless an exception is met. Patients must have approximately three months of non-operative conservative treatment, which may include NSAIDs (oral or topical), acetaminophen, and intra-articular corticosteroid injection as appropriate. Additionally, a trial of Physical Therapy within the last 12 months is required (e.g., supervised PT with >75% attendance, flexibility and strengthening exercises, activity modification). If PT is judged inappropriate, the medical record must clearly document the reason.

Background and Rationale

Knee arthroplasty (total and partial) is performed primarily for symptomatic knee arthritis — most commonly osteoarthritis, but also rheumatoid (inflammatory) arthritis and traumatic arthritis — with the goal of relieving pain and improving function. Indications include severe limitation in activities of daily living (difficulty walking, climbing stairs, squatting), chronic inflammation or stiffness not responsive to conservative therapy, and failure of nonoperative measures. The background also notes osteonecrosis and select cases of malignancy as additional reasons to proceed with total knee replacement, and describes revision arthroplasty as reoperation for failed prior replacements.

Clinical Grade Definitions and Indications

Kellgren-Lawrence Grade 3 definition

Definition (K-L Grade 3)Moderate: multiple osteophytes, definite narrowing of joint space, some sclerosis and possible deformity of bone ends

Source classificationKellgren-Lawrence system as described in the policy radiographic criteria for moderate to severe osteoarthritis

Relevance to coverageK-L Grade 3 radiographic findings satisfy the policy’s requirement for moderate-to-severe OA to consider knee arthroplasty medically necessary

Kellgren-Lawrence Grade 4 definition

Definition (K-L Grade 4)Severe: large osteophytes, marked narrowing of joint space, severe sclerosis and definite deformity of bone ends

Source classificationKellgren-Lawrence system as described in the policy radiographic criteria for moderate to severe osteoarthritis

Policy Review and Revision History

2026-05-05policy_reviewLatest

MPC approved adoption of the Kaiser Permanente National Total Knee Arthroplasty criteria to standardize the policy, with 60-day notice and planned effective date 2026-10-01.

2025-09-22coding_update

Updated applicable procedure codes referenced in the policy.

2024-07-01administrative_revision

OpenPayer

Clinical Review Criteria — Total Knee Arthroplasty