For any item to be covered by Medicare, it must: 1) be eligible for a defined
Medicare benefit category, 2) be reasonable and necessary for the diagnosis or
treatment of illness or injury or to improve the functioning of a malformed
body member, and 3) meet all other applicable Medicare statutory and
regulatory requirements.  
  
The purpose of a Local Coverage Determination (LCD) is to provide information
regarding "reasonable and necessary" criteria based on Social Security Act 
1862(a)(1)(A) provisions.  
  
In addition to the "reasonable and necessary" criteria contained in this LCD
there are other payment rules, which are discussed in the following documents,
that must also be met prior to Medicare reimbursement:

  * The LCD-related Standard Documentation Requirements Article, located at the bottom of this policy under the Related Local Coverage Documents section.

  * The LCD-related Policy Article, located at the bottom of this policy under the Related Local Coverage Documents section.

  * Refer to the Supplier Manual for additional information on documentation requirements.

  * Refer to the DME MAC web sites for additional bulletin articles and other publications related to this LCD.

  
For the items addressed in this LCD, the "reasonable and necessary" criteria,
based on Social Security Act  1862(a)(1)(A) provisions, are defined by the
following coverage indications, limitations and/or medical necessity.  
  
A lower limb prosthesis is covered when the beneficiary:

  1. Will reach or maintain a defined functional state within a reasonable period of time; and

  2. Is motivated to ambulate.

FUNCTIONAL LEVELS:  
  
A determination of the medical necessity for certain components/additions to
the prosthesis is based on the beneficiary's potential functional abilities.
Potential functional ability is based on the reasonable expectations of the
treating practitioner and prosthetist, considering factors including, but not
limited to:

  1. The beneficiary's past history (including prior prosthetic use if applicable); and

  2. The beneficiary's current condition including the status of the residual limb and the nature of other medical problems; and

  3. The beneficiary's desire to ambulate.

Clinical assessments of beneficiary rehabilitation potential must be based on
the following classification levels (see the FUNCTIONAL LEVEL CHARACTERISTICS
section in the LCD related Policy Article for additional details):  
  
Level 0: 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.  
  
Level 1: 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.  
  
Level 2: 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.  
  
Level 3: Has the ability or potential for ambulation with variable cadence.
Typical of the community ambulator who has the ability to traverse most
environmental barriers and may have vocational, therapeutic, or exercise
activity that demands prosthetic utilization beyond simple locomotion.  
  
Level 4: Has the ability or potential for prosthetic ambulation that exceeds
basic ambulation skills, exhibiting high impact, stress, or energy levels.
Typical of the prosthetic demands of the child, active adult, or athlete.  
  
The medical records must document the beneficiary's current functional and
physical capabilities and their expected functional potential, including an
explanation for the difference, if that is the case. It is recognized, within
the functional classification hierarchy, that bilateral amputees often cannot
be strictly bound by functional level classifications.  
  
GENERAL:  
  
If a prosthesis is denied as not reasonable and necessary, related additions
will also be denied as not reasonable and necessary.  
  
When an initial below knee prosthesis (L5500) or a preparatory below knee
prosthesis (L5510, L5520,L5530, L5540) is provided, prosthetic substitutions
and/or additions of procedures and components are covered in accordance with
the functional level assessment except for codes L5629, L5638, L5639, L5646,
L5647, L5704, L5785, L5962, and L5980 which will be denied as not reasonable
and necessary. When a below knee preparatory prefabricated prosthesis (L5535)
is provided, prosthetic substitutions and/or additions of procedures are
covered in accordance with the functional level assessment except for codes
L5620, L5629, L5645, L5646, L5670, L5676, L5704, and L5962 which will be
denied as not reasonable and necessary.  
  
When an above knee initial prosthesis (L5505) or an above knee preparatory
(L5560, L5570, L5580, L5590, L5595, L5600) prosthesis is provided, prosthetic
substitution and/or additions of procedures and components are covered in
accordance with the functional level assessment except for codes L5610, L5631,
L5640, L5642, L5644, L5648, L5705, L5706, L5964, L5980, and L5710, L5711,
L5712, L5714, L5716, L5718, L5722, L5724, L5726, L5728, L5780, L5790, L5795
which will be denied as not reasonable and necessary. When an above knee
preparatory prefabricated prosthesis (L5585) is provided, prosthetic
substitution and/or additions of procedures and components are covered in
accordance with the functional level assessment except for codes L5624, L5631,
L5648, L5651, L5652, L5705, L5706, L5964, and L5966 which will be denied as
not reasonable and necessary.  
  
In the following sections, the determination of coverage for selected
prostheses and components with respect to potential functional levels
represents the usual case. Exceptions will be considered in an individual case
if additional documentation is included which justifies the medical necessity.
Prostheses will be denied as not reasonable and necessary if the beneficiary's
potential functional level is 0.  
  
FEET:  
  
A determination of the type of foot for the prosthesis will be made by the
treating practitioner and/or the prosthetist based upon the functional needs
of the beneficiary. Basic lower extremity prostheses include a SACH foot.
Other prosthetic feet are considered for coverage based upon functional
classification.  
  
An external keel SACH foot (L5970) or single axis ankle/foot (L5974) is
covered for beneficiaries whose functional level is 1 or above.  
  
A flexible-keel foot (L5972) or multiaxial ankle/foot (L5978) is covered for
beneficiaries whose functional level is 2 or above.  
  
A microprocessor-controlled ankle foot system (L5973), energy storing foot
(L5976), dynamic response foot with multi-axial ankle (L5979), flex foot
system (L5980), flex-walk system or equal (L5981), or shank foot system with
vertical loading pylon (L5987) is covered when one of the following criteria
is met:

  1. The beneficiary's functional level is 3 or above; or,

  2. The beneficiary's functional level is 2; and,

    1. Meets the functional level 2 coverage criteria for a fluid, pneumatic, or electronic/microprocessor control addition for a prosthetic knee; and,

    2. A higher-level (i.e., functional level 3) foot is required for the safe and proper use of the prescribed knee system.

The microprocessor foot or ankle system addition _with_ power assist which
includes any type motor (L5969) is not covered because there is insufficient
information to demonstrate that the item meets the Medicare standard to be
considered reasonable and necessary as per PIM Chapter 13. Claims for L5969
will be denied as not reasonable and necessary.  
  
Coverage is extended only if there is sufficient clinical documentation of
functional need for the technologic or design feature of a given type of foot.
This information must be retained in the treating practitioner's or
prosthetist's files.  
  
A user-adjustable heel height feature (L5990) will be denied as not reasonable
and necessary.  
  
KNEES:  
  
A determination of the type of knee for the prosthesis will be made by the
treating practitioner and/or the prosthetist based upon the functional needs
of the beneficiary. Basic lower extremity prostheses include a single axis,
constant friction knee. Other prosthetic knees are considered for coverage
based upon functional classification.  
  
A high activity knee control frame (L5930) is covered for beneficiaries whose
functional level is 4.  
  
A fluid or pneumatic knee unit (L5610, L5613, L5614, L5615, L5722, L5724,
L5726, L5728, L5780, L5814, L5822, L5824, L5826, L5828, L5830, L5840), or
control addition, fluid (L5848), or electronic/microprocessor (L5856, L5857,
L5858) is covered for beneficiaries whose functional level is 3 or above.

A fluid or pneumatic knee unit (L5610, L5613, L5614, L5615, L5722, L5724,
L5726, L5728, L5780, L5814, L5822, L5824, L5826, L5828, L5830, L5840), or
control addition, fluid (L5848), or electronic/microprocessor (L5856, L5857,
L5858) is also covered under limited circumstances for beneficiaries whose
functional level is 2, when all of the following criteria (1-3) are met (see
the POLICY SPECIFIC DOCUMENTATION REQUIREMENTS section in the LCD related
Policy Article):

  1. The beneficiary has had a clinical evaluation to determine their functional level (see FUNCTIONAL LEVELS section above); and,

  2. Supporting documentation in the medical record outlines, in the context of the beneficiary's overall medical health, the rationale for selection of a fluid, pneumatic, or electronic/microprocessor-controlled knee, including (at minimum) how the selected knee will:

    1. Improve the beneficiary's functional health outcomes (e.g., fall reduction, injury prevention, lower energy expenditure); and,

    2. Help the beneficiary accomplish their activities of daily living (ADLs); and,

  3. All lower-level knee systems (e.g., knee systems which exclude use of fluid, pneumatic, or microprocessor) have been considered and ruled out based on the beneficiary's specific functional and medical needs.

In addition, for coverage of an electronic/microprocessor-controlled knee
system (L5856, L5857, or L5858 plus associated components) for beneficiaries
whose functional level is 2, all of the following criteria (1-4) must also be
met (see the POLICY SPECIFIC DOCUMENTATION REQUIREMENTS section in the LCD
related Policy Article):

  1. The electronic/microprocessor knee is indicated for functional level 2; and,

  2. The electronic/microprocessor knee has integrated technology that allows the knee to detect when the user trips or stumbles and can automatically adjust to stabilize the knee unit (e.g., stumble recovery); and,

  3. The beneficiary is able to make use of a product that requires daily charging; and,

  4. The beneficiary is able to understand and respond to error alerts and alarms indicating problems with the function of the unit.

  
L5859 (ADDITION TO LOWER EXTREMITY PROSTHESIS, ENDOSKELETAL KNEE-SHIN SYSTEM,
POWERED AND PROGRAMMABLE FLEXION/EXTENSION ASSIST CONTROL, INCLUDES ANY TYPE
MOTOR(S)) is only covered when the beneficiary meets all of the criteria
below:

  1. Has a microprocessor (swing and stance phase type (L5856)) controlled (electronic) knee

  2. K3 functional level only

  3. Has a documented comorbidity of the spine and/or sound limb affecting hip extension and/or quadriceps function that impairs K3 level function with the use of a microprocessor-controlled knee alone

  4. Is able to make use of a product that requires daily charging

  5. Is able to understand and respond to error alerts and alarms indicating problems with the function of the unit

  
If these coverage criteria for the knee component are not met, L5859 will be
denied as not reasonable and necessary.  
  
Other knee systems (L5611, L5616, L5710, L5711, L5712, L5714, L5716, L5718,
L5810, L5811, L5812, L5816, L5818) are covered for beneficiaries whose
functional level is 1 or above.  
  
Coverage is extended only if there is sufficient clinical documentation of
functional need for the technologic or design feature of a given type of knee.
This information must be retained in the treating practitioner's or
prosthetist's files.  
  
ANKLES:  
  
An axial rotation unit (L5982, L5984, L5985, L5986) is covered for
beneficiaries whose functional level is 2 or above.  
  
HIPS:  
  
A pneumatic or hydraulic polycentric hip joint (L5961) is covered for
beneficiaries whose functional level is 3 or above.  
  
SOCKETS:  
  
More than 2 test (diagnostic) sockets (L5618, L5620, L5622, L5624, L5626,
L5628) for an individual prosthesis are not reasonable and necessary unless
there is documentation in the medical record which justifies the need.
Exception: A test socket is not reasonable and necessary for an immediate
prosthesis (L5400, L5410, L5420, L5430, L5450, L5460).  
  
No more than two of the same socket inserts (L5654, L5655, L5656, L5658,
L5661, L5665, L5673, L5679, L5681, L5683) are allowed per individual
prosthesis at the same time.  
  
Socket replacements are considered reasonable and necessary if there is
adequate documentation of functional and/or physiological need. It is
recognized that there are situations where the explanation includes but is not
limited to: changes in the residual limb; functional need changes; or
irreparable damage or wear/tear due to excessive beneficiary weight or
prosthetic demands of very active amputees.  
  
GENERAL

A Standard Written Order (SWO) must be communicated to the supplier before a
claim is submitted. If the supplier bills for an item addressed in this policy
without first receiving a completed SWO, the claim shall be denied as not
reasonable and necessary.

For Durable Medical Equipment, Prosthetics, Orthotics and Supplies (DMEPOS)
base items that require a Written Order Prior to Delivery (WOPD), the supplier
must have received a signed SWO before the DMEPOS item is delivered to a
beneficiary. If a supplier delivers a DMEPOS item without first receiving a
WOPD, the claim shall be denied as not reasonable and necessary. Refer to the
LCD-related Policy Article, located at the bottom of this policy under the
Related Local Coverage Documents section.

For DMEPOS base items that require a WOPD, and also require separately billed
associated options, accessories, and/or supplies, the supplier must have
received a WOPD which lists the base item and which may list all the
associated options, accessories, and/or supplies that are separately billed
prior to the delivery of the items. In this scenario, if the supplier
separately bills for associated options, accessories, and/or supplies without
first receiving a completed and signed WOPD of the base item prior to
delivery, the claim(s) shall be denied as not reasonable and necessary.

An item/service is correctly coded when it meets all the coding guidelines
listed in CMS HCPCS guidelines, LCDs, LCD-related Policy Articles, or DME MAC
articles. Claims that do not meet coding guidelines shall be denied as not
reasonable and necessary/incorrectly coded.

Proof of delivery (POD) is a Supplier Standard and DMEPOS suppliers are
required to maintain POD documentation in their files. Proof of delivery
documentation must be made available to the Medicare contractor upon request.
All services that do not have appropriate proof of delivery from the supplier
shall be denied as not reasonable and necessary.



The aim of this summary of evidence was to determine if the use of MPKs with
stumble recovery, or similar technology, compared to NMPKs improved the rate
of falls, risk of falling, fear of falling, and gait performance in MFCL-2
Medicare beneficiaries with lower limb amputations requiring a prosthetic
knee. Studies that were reviewed were analyzed for risk of bias (ROB). For
RCTs, ROB was assessed using the Cochrane Collaboration's tool for assessing
risk of bias.55,56 To evaluate the ROB in non-randomized studies, the ROB in
Non-Randomized Studies of Interventions (ROBINS-I) tool was used.57 The
Grading of Recommendations, Assessment, Development, and Evaluation (GRADE)
approach was used as a method of grading the certainty of evidence, which can
range from high to very low, and is defined as follows:58

**Certainty of Evidence** | **Definition**  
---|---  
High | Further research is very unlikely to change our confidence in the
estimate of effect  
Moderate | Further research is likely to have an important impact on our
confidence in the estimate of effect and may change the estimate  
Low | Further research is very likely to have an important impact on our
confidence in the estimate of effect and is likely to change the estimate  
Very Low | Any estimate of effect is very uncertain  
  


**Certainty of Evidence**

Fall Rate: Low to Very Low

  * Number of Falls based on RCTs: Low
  * Number of Falls based on observational studies: Very Low
  * Fall Rate on a 5-point scale based on an observational study: Very Low
  * Number of Uncontrolled Falls based on an observational study: Very Low

Risk of Falling: Low to Very Low

  * Timed up and go (TUG) based on RCTs: Low
  * BERG balance scale (BBS) based on an RCT: Low
  * Four Square Strep Test (FSST) based on an RCT: Low
  * Prosthesis Evaluation Questionnaire (PEQ-A) based on an RCT: Low
  * Modified PEQ-A based on an observational study: Very Low
  * Activities Specific Balance Confidence (ABC) based on an observational study: Very Low
  * Prosthetic Limb User Survey of Mobility 12-item Short Form (PLUS-M) based on observational studies: Very Low
  * Test of Functional Mobility (L-test) based on an observational study: Very Low

Fear of Falling: Low to Very Low

  * Modified Fall Efficacy Scale (MFES) based on an RCT: Low
  * Self-reported fear of falling based on observational studies: Very Low
  * Customized PEQ-A Addendum based on observational studies: Very Low

Gait Performance: Low to Very Low

  * 10-meter walk test (10MWT); 6-minute walk test (6MWT) follow-up: 13 months based on an RCT: Low
  * 3D gait analysis generated gait profile score follow-up: 6 months based on an observational study: Very Low
  * Gait Complexity Calculation based on an observational study: Very Low
  * Gait Harmonizing Scale, Gait Cadence Variance Scale based on an observational study: Very Low
  * Stair descent, Uneven Terrain Walking Speed based on observational studies: Very Low
  * Function on an incline based on an observational study: Very Low

MPK Comparison in Fall Rate: Low to Very Low

  * Assessment of Daily Activity Performance in Transfemoral Amputees (ADAPT) based on an RCT: Low
  * Self-reported rate of injurious falls based on an observational study: Very Low

**Conclusion**

Microprocessor-controlled prosthetic knees use integrated sensors and
computers to collect and analyze data to adjust flexion and extension
resistance of the prosthetic joint during the swing- and/or stance-phase of
the gait cycle in real time. Purported benefits of MPKs compared to NMPKs
include improved stability when the user is standing and walking, as well as
fall prevention with the addition of technology which can automatically
increase resistance in the knee unit to provide support when a stumble is
detected.

The use of an MPK compared to a NMPK may reduce the rate of falling, risk of
falling and fear of falling, as well as improve gait performance in
individuals with lower limb amputations requiring a prosthetic knee who are
classified as limited community ambulators (i.e., MFCL-2), based on low to
very low certainty evidence. While multiple studies examining these outcomes
were limited by their nonrandomized design, small sample sizes, missing data,
uncertainty related to the directness of the study cohorts, and/or reliance on
outcome measures that are subject to recall or response bias, the conclusions
of the studies were consistent, with no studies finding outcomes favoring
NMPKs compared to MPKs. Additionally, computer simulated impact modeling
suggest a large effect size related to both the incidence of falls and risk of
falling in MPK users compared to NMPK users. Also notable, no studies were
identified to support that the benefits of MPKs are limited to individuals
classified as MFCL-3 and above; however, the currently available literature is
insufficient to support extending coverage of MPKs to MFCL-1 beneficiaries. Of
the original research analyzed for the Summary of Evidence, only one study
included any MFCL-1 participants.

Microprocessor-controlled prosthetic knees may be a viable therapeutic option
for some limited community ambulating Medicare beneficiaries with lower limb
amputations. Therefore, the criteria in the Lower Limb Prostheses Local
Coverage Determination will be expanded to allow coverage of fluid, pneumatic,
or electronic/microprocessor control additions for prosthetic knees in MFCL-2
beneficiaries when supporting documentation in the medical record outlines the
rationale for selection of the higher-level knee. This documentation must
include how the selected knee will improve the beneficiary's functional health
outcomes, will help the beneficiary accomplish their activities of daily
living, and that all alternative lower-level knee options have been considered
and ruled out based on the beneficiary's individual functional and medical
needs.

In addition, for coverage of electronic/microprocessor-controlled knees for
MFCL-2 beneficiaries, the MPK provided must be indicated for functional level
2 individuals and include integrated technology that allows the knee to detect
when the user stumbles, automatically increases resistance in the knee to
provide support for recovery, and potentially prevents a fall. Furthermore,
the LCD stipulates that the beneficiary is able to make use of a product that
requires daily charging and can understand and respond to alerts/alarms which
may indicate knee dysfunction.

Criteria of higher-level foot systems will also be expanded to include MFCL-2
beneficiaries who meet the new coverage criteria for a fluid, pneumatic, or
electronic/microprocessor control addition for a prosthetic knee, and who will
require a compatible foot.