Coverage of Conditions and Treatments (Coverage Decisions)

Use this lookup tool to determine coverage decisions, or if prior authorization is needed for the treatment or condition. Note: For Self-insured employer claims, you must contact the employer or their claims administrator.

List also available in PDF format.

Archived Coverage Decisions.

See Treatment Guidelines and Resources for additional information.

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Coverage decision

Microprocessor-controlled lower limb prosthesis for the knee is a covered benefit with conditions for State Fund, Self-Insured and Crime Victims claims.

Microprocessor-controlled lower limb prosthesis for the feet and ankle is not a covered benefit.


Microprocessor-controlled prosthetic (MCP) knees for above-the-knee amputees use computers to enhance basic mechanical knee designs. Sensors incorporated into the prosthesis gather data to determine stance phase and swing phase control. As a result, the prosthesis responds to changing conditions while ambulating.

Prior authorization criteria

Use the L&I Prosthetic Device Request Form, with addendum for microprocessor.

The recommendation for the microprocessor knee must come from a physician (MD or DO) who specializes in functional rehabilitation of amputees.

To meet the criteria for coverage of MCP knee, the worker must have:

  • Condition of transfemoral amputation, knee disarticulation or hip disarticulation allowed on the claim.
  • Medicare Functional Classification Level K3 or K4. The physician must submit documentation of the assessment(s) used to derive the K level. Authorization may be considered for K2 functional level in certain circumstances, see below.
  • Adequate hip flexion, i.e., less than 20 degrees hip flexion contracture.
  • Adequate skin integrity, i.e., no current skin breakdown, open wounds or infections, or frequent history of such.
  • Actual or anticipated ability to tolerate wearing prosthesis for at least 6 hours per day.
  • Ability to don and doff the leg independently.
  • Sufficient cognitive ability to learn how to properly use the proposed knee in the course of normal daily living.
  • Documented history of compliance with rehabilitative medical care.
  • Access to a prosthetist with documented experience and knowledge of the proposed device, and the capability of performing the necessary maintenance and repairs.
  • A successful trial using the device, or prior experience if it is a replacement.
  • Agreement to use the device within manufacturer’s specifications, including but not limited to:
    • Weight limits: includes both the worker’s body weight and the weight lifted or carried in daily activities and/or job duties.
    • Environmental exposures: microprocessor devices should not be used in conditions of high moisture/humidity, or high levels of dust.

A worker at a K2 functional level can be considered for authorization with additional criteria. The worker must have training in use of the knee by a physical therapist experienced in prosthetics. Authorization may be given if the worker has a need related to physical work demands or fall prevention, such as:

  • The MCP knee permits a worker to return to work or be considered employable because use of the knee is expected to advance the worker to a K3 functional level, OR
  • There is a documented safety concern that will be addressed by using a MCP knee, such as high risk for falls (e.g., has had documented falls using an advanced swing and stance phase control hydraulic knee unit, or has documented medical comorbidities that impact balance).

Note: Specialized microprocessor knees to include the Ottobock Genium, and Ossur Power Knee, are considered on a case by case basis.

Background and State Health Technology Assessment

On November 18, 2011, the State Health Technology Clinical Committee (HTCC) met in an open public meeting to review the evidence for microprocessor-controlled lower limb prosthetics. Based on a review of the best available evidence of safety, efficacy and cost-effectiveness, the committee’s determination is that MCP knees are covered with certain limitations. The determination was made final by the HTCC on March 16, 2012. Complete information on this HTCC determination is available at: What we're working on | Washington State Health Care Authority.

Billing and payment

Primary Codes:
  • L5856 - Addition to lower extremity prosthesis, endoskeletal knee‐shin system, microprocessor control feature, swing and stance phase, includes electronic sensor(s), any type
  • L5857 - Addition to lower extremity prosthesis,endoskeletal knee‐shin system, microprocessor control feature, swing phase only, includes electronic sensor(s),any type
  • L5858 - Addition to lower extremity prosthesis, endoskeletal knee‐shin system, microprocessor control feature, stance phase only
  • L5859 - Addition to lower extremity prosthesis, endoskeletal knee-shin system, powered and programmable flexion/extension assist control, includes any type motor(s)
Common add on codes:
  • L5828 - Addition, endoskeletal knee-shin system, single axis, fluid swing and stance phase control
  • L5845 - Addition, endoskeletal knee-shin system, stance flexion feature, adjustable
  • L5848 - Addition to endoskeletal knee-shin system, fluid stance extension, dampening feature, with or without adjustability
  • L5930 - Addition, endoskeletal system, high activity knee control frame
  • L7368 - Lithium Ion Battery Charger, Replacement only


Microprocessor-controlled lower limb prostheses are prosthetic devices that include sensors to detect users’ movements and computers to adjust behavior of the limb during gait.

K Functional level: Medicare functional classification levels (MFCL) for amputees
  • 0 - The patient does not have the ability or potential to ambulate or transfer safely with or without assistance and a prosthesis does not enhance their quality of life or mobility.
  • 1 - The patient has the ability or potential to use a prosthesis for transfers or ambulation on level surfaces at fixed cadence. Typical of the limited and unlimited household ambulator.
  • 2 - The patient has the ability or potential for ambulation with the ability to traverse low level environmental barriers such as curbs, stairs or uneven surfaces. Typical of the limited community ambulator.
  • 3 - The patient has the ability or potential for ambulation with variable cadence. Typical of the community ambulator who has the ability to transverse most environmental barriers and may have vocational, therapeutic or exercise activity that demands prosthetic utilization beyond simple locomotion.
  • 4 - The patient has the ability or potential for prosthetic ambulation that exceeds the basic ambulation skills, exhibiting high impact, stress, or energy levels, typical of the prosthetic demands of the child, active adult, or athlete.