Lower limb prosthesis complies with Triple-S medical criteria for coverage when the following general criteria are met:
• The patient can reach or maintain a functional state defined by a reasonable period of time;
• The patient is motivated to ambulate; and
• The prosthesis is incident to the services of a physician or ordered by a physician.
The determination of medical criteria for coverage of prostheses is also based on the potential of functional level of the patient:
Key point
According to the National Center for Health Statistics of the U.S. there are approximately 200,000 new amputations in the United States each year. Approximately 70% are amputations of lower limbs.
People with lower limb amputations walk slower and use a less efficient asymmetric gait compared with normal subjects with non-pathological gait. The more proximal the amputations are, the more exacerbated these differences will be.
Functional Levels
The determination of the medical necessity of certain components/additions to the prosthesis is based on potential of functional capabilities of the beneficiary. The potential of functional ability is based on the reasonable expectations of the technician, and medical treatment, considering factors including, but not limited to:
a. The past history of the beneficiary (including the use of prior prosthesis if it proceeds); and
b. Current condition of the beneficiary including the state of the stump and the nature of other medical problems; and
c. The desire of the beneficiary to ambulate.
Clinical evaluations of the potential for rehabilitation of the patient should be based on the following classification levels. Medical records must document the functional capabilities of the patient and his/her expected functional potential, including an explanation of the difference, if that is the case.
Clinical evaluations of rehabilitation potential of the beneficiary should be based on the following classification levels:
Level 0: Does not have the ability or potential to ambulate or transfer securely with or without assistance and prosthesis does not improve his/her quality of life or mobility.
Level 1: Has the ability or potential to use prosthesis for transfer or ambulation on level surfaces at fixed cadence. Typical ambulator: at home either limited or unlimited.
Level 2: Has the ability or potential for ambulation with the ability to traverse environmental barriers of low level, such as curbs, stairs or uneven surfaces. Typical ambulator: limited community.
Level 3: Has the ability or potential for ambulation with variable cadence. Typical ambulator: in the community, has the ability to traverse most of the environmental barriers and may have the need for professional activity, therapeutic activity, or exercise that requires the use of prosthesis beyond simple locomotion.
Level 4: Has the ability or potential for ambulation that exceeds the basic needs of locomotion, which exhibit high levels of impact, stress, or energy. This characteristic is typical of the demands of prosthesis of the child, active adult, or an athlete.
The replacement or repair of parts or prosthesis will have coverage when there is adequate documentation of the functional and/or physiological need such as, but not limited to, changes in the stump, changes in functional need, or an irreparable damage or due to the excessive weight of the patient or demands of prosthesis of very active amputees.
Lower limb prosthesis is covered when the beneficiary:
1. Needs to reach or maintain a defined functional state in a reasonable period of time; and
2. Is motivated to ambulate.
Records must document the capabilities of the current functional beneficiaries and their expected functional potential, including an explanation of the difference, if that is the case. It is recognized, within the functional classification hierarchy, that bilateral amputees If prosthesis is denied as not reasonable or not necessary, related additions will also be denied as not reasonable and not necessary.
When authorizing an initial prosthesis below the knee (L5500) or preparatory prosthesis below the knee (L5510-L5530, L5540), substitutions and/or additions of procedures and prosthetic components are covered in accordance with the assessment at the functional level, except codes L5629, L5638, L5639, L5646, L5647, L5704, L5785, L5962, L5980 which will be denied as not reasonable and not necessary. When a prefabricated preparatory prosthesis is provided below the knee (L5535), substitutions and/or additions of prosthetic procedures are covered according to the functional level assessment, except for codes L5620, L5629, L5645, L5646, L5670, L5676, L5704, L5962, which will be denied as not reasonable and not necessary.
When authorizing an initial prosthesis over the knee (L5505) or a preparatory prosthesis over the knee (L5560-L5580, L5590-L5600) is provided, the substitutions and/or additions of procedures and prosthetic 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-L5780, L5790-L5795, which will be denied as not and not necessary. When providing a prefabricated preparatory prosthesis over the knee (L5585), the substitution and/or additions of procedures and prosthetic 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 not necessary.
In the following sections, the determination of coverage for prosthetics and components selected with respect to the potential functional levels represents the usual case. Exceptions will be considered on an individual case if additional documentation is included that justifies the medical necessity. The prosthesis will be denied as not reasonable and not necessary if the potential functional level of the beneficiary is of 0.
Feet
A determination of the type of foot for the prosthesis will be made by the treating physician and/or the prosthesis technician in accordance with the functional needs of the beneficiary. Basic lower extremity prostheses include a SACH Foot. Other prosthetic feet are considered for the coverage based on the functional classification.
A SACH foot external keel (L5970) or ankle/foot of a single axis (L5974) is covered for beneficiaries whose functional level is 1 or higher.
A foot flexible-keel (L5972) or ankle/multiaxial foot (L5978) is covered for those beneficiaries whose functional level is 2 or higher.
A system of ankle and foot controlled by a microprocessor (L5973), with energy storage (L5976), dynamic response foot with multi-axial ankle (L5979), flex feet system (L5980), flex-a system for foot or equal (L5981), or shank foot system with vertical loading pylon (L5987) is covered for beneficiaries whose functional level is 3 or higher.
The coverage extends only if there is sufficient clinical documentation of functional need of the technological function, or the design of a given type of foot. This information of the prosthesis must be documented and retained in the archives of the physician.
A heel of adjustable height by the user (L5990) will be denied as not reasonable and necessary. The basic prosthesis of lower extremity includes only one axis and the constant friction knee. Other prosthetic knees are considered for the coverage on the basis of the functional classification.
A framework of control of high activity knee (L5930) is covered for beneficiaries whose functional level is 4.
The pneumatic knee or electronic knee is covered (L5610, L5613, L5614, L5722-L5780, L5814, L5822-L5840 – L5848, L5856, L5857, L5858) for beneficiaries whose functional level is 3 or higher.
Other knee systems are covered (L5611, L5616, L5710-L5718, L5810-L5812, L5816, L5818) for those beneficiaries whose functional level is 1 or higher.
Ankle
A unit of axial rotation (L5982-L5986) is covered for beneficiaries whose functional level is 2 or higher.
Hips
A polycentric hip joint, pneumatic or hydraulic (L5961) is covered for beneficiaries whose functional level is 3 or higher.
Bases
More than 2 testing sockets (diagnostic) (L5618-L5628) for an individual prosthesis are not reasonable and necessary unless there is documentation justifying the need. Exception: A test plug is not reasonable and necessary for an immediate prosthesis (L5400-L5460).
