L5840 — Addition, endoskeletal knee/shin system, 4-bar linkage or multiaxial, pneumatic swing phase control
L5840 is a HCPCS Level II code for addition, endoskeletal knee/shin system, 4-bar linkage or multiaxial, pneumatic swing phase control. It belongs to the Orthotic and Prosthetic Procedures and Devices section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Medically Unlikely Edits — units per day
The most units of L5840 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
- DME supplier
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for L5840
- Long descriptor
- Addition, endoskeletal knee/shin system, 4-bar linkage or multiaxial, pneumatic swing phase control
- Short descriptor
- Multi-axial knee/shin system
- Added
- January 1, 1994
- BETOS
- D1F
- Pricing indicator
- 38 — DMEPOS
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Orthotics, prosthetics, prosthetic devices and vision services. Price subject to floors and ceilings.
Codes adjacent to L5840
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If L5840 is not quite right, the correct code is very often within a few positions of it.
- L5816Addition, endoskeletal knee-shin system, polycentric, mechanical stance phase lock
- L5818Addition, endoskeletal knee-shin system, polycentric, friction swing, and stance phase control
- L5822Addition, endoskeletal knee-shin system, single axis, pneumatic swing, friction stance phase control
- L5824Addition, endoskeletal knee-shin system, single axis, fluid swing phase control
- L5826Addition, endoskeletal knee-shin system, single axis, hydraulic swing phase control, with miniature high activity frame
- L5827Endoskeletal knee-shin system, single axis, electromechanical swing and stance phase control, with or without shock absorption and stance extension damping
- L5828Addition, endoskeletal knee-shin system, single axis, fluid swing and stance phase control
- L5830Addition, endoskeletal knee-shin system, single axis, pneumatic/ swing phase control
- L5841Addition, endoskeletal knee-shin system, polycentric, pneumatic swing, and stance phase control
- L5845Addition, endoskeletal, knee-shin system, stance flexion feature, adjustable
- L5848Addition to endoskeletal knee-shin system, fluid stance extension, dampening feature, with or without adjustability
- L5850Addition, endoskeletal system, above knee or hip disarticulation, knee extension assist
- L5855Addition, endoskeletal system, hip disarticulation, mechanical hip extension assist
- L5856Addition to lower extremity prosthesis, endoskeletal knee-shin system, microprocessor control feature, swing and stance phase, includes electronic sensor(s), any type
- L5857Addition to lower extremity prosthesis, endoskeletal knee-shin system, microprocessor control feature, swing phase only, includes electronic sensor(s), any type
- L5858Addition to lower extremity prosthesis, endoskeletal knee shin system, microprocessor control feature, stance phase only, includes electronic sensor(s), any type
Questions about L5840
What is HCPCS code L5840?
L5840 is a HCPCS Level II code for addition, endoskeletal knee/shin system, 4-bar linkage or multiaxial, pneumatic swing phase control. It sits in the Orthotic and Prosthetic Procedures and Devices section.
Does Medicare cover L5840?
The CMS HCPCS file marks L5840 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.