L1846, Knee orthosis, double upright, thigh and calf, with adjustable flexion and
HCPCS/CPT
Prior Authorization
Prior Auth Required
Code explicitly requires prior authorization (high confidence)
Documentation Required
- A Standard Written Order (SWO) must be communicated to the supplier before a claim is submitted; for items requiring WOPD, a signed SWO/WOPD must be received prior to delivery.
- Proof of delivery (POD) documentation must be maintained by the supplier and made available to the Medicare contractor upon request.
- Objective knee instability must be supported by documentation of the beneficiary’s physical examination including the joint laxity test(s) performed when required by the orthosis coverage criteria.
- Medical record must document why a custom fabricated orthosis is medically necessary instead of a prefabricated orthosis (e.g., deformity, limb size, minimal muscle mass); absence of this documentation will result in denial.
Key Coverage Criteria
- An item is covered only if it meets Medicare benefit category eligibility, is reasonable and necessary for diagnosis/treatment or to improve functioning of a malformed body member, and meets all other Medicare statutory and regulatory requirements.
- Prefabricated knee orthoses with joints or with condylar pads and joints (HCPCS L1810, L1812, L1820, L1821) are covered for ambulatory beneficiaries with knee weakness or deformity who require stabilization.
- Knee orthoses with a locking knee joint or rigid knee orthoses (HCPCS L1831, L1836) are covered for beneficiaries with knee flexion or extension contractures who demonstrate at least 10 degrees of movement on passive range of motion testing (nonfixed contracture).
- Immobilizer knee orthosis without joints (HCPCS L1830) is covered for beneficiaries with a recent knee injury or recent knee surgical procedure (see related ICD-10 Groups 2 or 4).
- Knee orthoses with adjustable knee joints (HCPCS L1832, L1833) are covered when the beneficiary has a recent knee injury or knee surgery (Groups 2 or 4) or is ambulatory with objective knee instability (Group 4).
- Prefabricated Swedish-type knee orthosis (HCPCS L1850) is covered for ambulatory beneficiaries with knee instability due to genu recurvatum (hyperextended knee) (Group 5).
4 Active Policies
ANTHEM-GL-B088536, CG-OR-PR-03 Custom-made Knee Braces
L33318, Knee Orthoses
EVICORE-HPLAN-CIGNA-3C6BF790C032, Cigna Commercial DME Code List - Effective 03/07/2026
EVICORE-HPLAN-CIGNA-1815296EE67F, Cigna Comprehensive Code List - Effective 03/07/2026
Related Codes
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