FUNCTIONAL OUTCOMES IN PROSTHETICS

Functional Outcomes

• Importance of Functional Outcome tools– PT reimbursement: G-Codes required by

Medicare currently. Ability to document using a functional outcome measure most objective

– Prosthetic industry changes: ability to document patient improvement/potential helps justification with insurance

– Justifies treatment/services– Tool to document progression

Functional Outcomes

• 1995- Medicare adopted K-levels to describe “ability of a patient to reach a defined functional state within a reasonable period of time”

• Functional level of patient determines componentry- foot and knee

• Based on current medical status, comorbidities and desire to ambulate (subjective)

Functional OutcomesK-Levels

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 records must document the beneficiary's current functional capabilities and his/her 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

-Noridian Healthcare Solutions, LCD Lower Limb Prostheses, ID#L11453

Functional Outcomes

• Medicare dictates componentry based on K-Level• Higher K-Level = more advanced technology and

materials, increased cost• Example-feet

– K0: n/a– K1: SACH foot– K2: multiaxial foot– K3: flex foot– K4: all

Functional Outcomes• Types of measure– Self report– Physical performance– Professional report

MDC- minimum amount of change in score to ensure result isn’t due to measurement error

Functional Outcomes

Self Report• Pain/Socket Fit Comfort• Lower Extremity Functional Scale• Other mobility scales

Functional Outcomes

Physical Performance• Amputee Mobility Predictor(AMP-Pro,-noPro)• Timed Up and Go (TUG)• L Test• 6 Minute Walk test

Functional Outcomes

Amputee Mobility Predictor- AMP• Objective assessment of patient’s ability to

ambulate with prosthesis• Assist with K Level determination• AMP Pro…with prosthesis• AMP NoPro…without prosthesis• Same test• Arch Phys Med Rehabil Vol 83, May 2002

Robert S. Gailey, PhD, PT

Functional Outcomes

AMP- continued• 20 functional measurement items• Progress from least to most difficult• Approx 10-15 minutes• MDC established at 3.4• CPT 97750

AMP Scoring

K0 K1 K2 K3 K4AMP Pro n/a 15-26 27-36 37-42 43-47

AMP NoPro 0-8 9-20 21-28 29-36 37-43

Timed Up and Go- TUG

MDC 3.6 secTT norms 23.1 secTF norms 28.3 sec

Minimal detectable change has been established at 3.0

L- Test

-Modified version of TUG

-Developed for higher activity patients v. TUG

-Validated against TUG, 2MWT and 10MWT

J. APTA, July 2005, Vol 85, no.7

6 Minute Walk Test

• Ambulate for 6 minutes, record distance• 2 MWT highly correlates to 6MWT

Population Mean +/- SD Range

Lower limb amputee (K1)* 50 +/- 30 m 4-96

Lower limb amputee (K2)* 190 +/- 111 m 16-480

Lower limb amputee (K3)* 299 +/- 102 m 48-475

Lower limb amputee (K4)* 419 +/- 86 m 264-624

Health elderly adults^ 417 +/- 95 m n/a

*Gailey et al, 2002

Documentation• Document using language consistent with Medicare’s

language.– Mention the patient’s desire to ambulate.– State that the patient can vary their walking cadence (K3)– Document the patient’s ability to traverse low level

barriers (K2)• Document specific functional limitations• Document comorbidities thoroughly• Document prior level of function

Reasons for denial:• Documentation doesn't support the selected

functional level• Inadequate documentation that the patient will

reach or maintain a defined functional level within a reasonable time period

• No corroborating information in the physician's records

• No documentation that the patient is "motivated to ambulate"