Summary & Overview
HCPCS L5613: Addition to Above-Knee Prosthetic, 4-Bar Hydraulic Swing Knee
HCPCS Level II code L5613 denotes an add-on endoskeletal prosthetic knee component for above-knee through knee-disarticulation amputations: a 4-bar linkage with hydraulic swing phase control. This code identifies a specific advanced mechanical knee addition that affects mobility outcomes and device selection for persons requiring transfemoral or knee-disarticulation prostheses. Nationally, coding for specialized prosthetic components matters for clinical care planning, device standardization, and payer coverage determinations for durable medical equipment and prosthetics.
Key payers in scope include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of the component and service context, common billing modifiers and service line considerations, and references to typical sites of service. The publication covers expected documentation elements, common payer considerations, and how this component maps to prosthetic service workflows. It also highlights clinical implications tied to gait mechanics and rehabilitation needs, as well as benchmarking and policy update topics where data is available. Data not available in the input is noted where applicable; this summary focuses on the code definition, service type, and national payer context rather than state-specific rules.
Billing Code Overview
HCPCS Level II code L5613 describes an addition to a lower extremity prosthetic endoskeletal system for an above knee to knee disarticulation amputation level. The component is a 4-bar linkage prosthetic knee mechanism that includes hydraulic swing phase control, intended to modulate limb swing dynamics during ambulation.
Service type: Prosthetic component — lower extremity, knee joint mechanism (endoskeletal addition)
Typical site of service: Prosthetics and orthotics clinic, hospital outpatient prosthetics department, or specialized rehabilitation facility
Clinical & Coding Specifications
Clinical Context
A typical patient is a unilateral above-knee or knee-disarticulation amputee being fitted or refitted with an endoskeletal lower-extremity prosthetic knee joint featuring a 4-bar linkage and hydraulic swing-phase control. The clinical workflow begins with a prosthetist evaluation including residual limb assessment, functional level determination (K-level), and gait analysis. The prosthetist documents objectives such as improved swing-phase control, cadence variability, and safety for community ambulation. Fabrication involves ordering the L5613 component as an addition to an existing endoskeletal prosthesis or as part of a new limb assembly. Delivery includes alignment, socket interface adjustments, and dynamic gait training with the physical therapist. Follow-up visits address fit, component tuning, and functional outcome measures; billing reflects the L5613 addition alongside socket, knee, and foot components and appropriate modifiers for billing circumstances such as bilateral fitting (50), professional component (26), or replacement (RR). Payors commonly involved: Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, BUCA, and Medicare.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|