Clinical trial NCT01537211: Functional Outcomes in Dysvascular Transfemoral Amputees
Official title: Microprocessor Knee Versus Mechanical Knee: Impact on Functional Outcomes in Dysvascular Transfemoral Amputees
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Transfemoral Amputation
Unilateral Traumatic Amputation of Leg at or Above Knee
Keywords: Dysvascular
amputation
above knee
ambulation
Lead sponsor: Shirley Ryan AbilityLab
Sponsor class: OTHER
Collaborators: name: Otto Bock Healthcare
First posted: 2012-02-23
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: In older adults, poor circulation in the lower extremities leads to serious health complications including limb loss. In addition, individuals with dysvascular disease also suffer from other co-morbidities like diabetes, coronary and cerebrovascular disease. An individual with a transfemoral (TF) amputation is usually fitted with a prosthetic limb to assist with function, including a prosthetic knee and a prosthetic foot. Currently, dysvascular amputees are given a prosthetic knee based on the basic expectation that they will be functionally stable. This consideration does not address higher levels of function like walking at multiple speeds and over uneven ground. Also, dysvascular amputees are not able to counteract their co-morbidities with a more active lifestyle. Walking is less energy efficient; their traditional prostheses may cause early onset of fatigue and induce a fear of falling. Newer microprocessor knees enable patients with transfemoral amputations to walk on different surfaces and at multiple cadences through better control in swing and stance phases of gait. The impact of the functional differences in the prostheses is not clear and requires additional investigation to clarify the choice of the most appropriate functional prosthesis. The purpose of this study is to compare the functional outcomes with the traditional mechanical knee versus the microprocessor knee (C-leg) in transfemoral amputees.

Detailed description: In older adults, poor circulation in the lower extremities or dysvascular disease can lead to serious health complications. In addition, these individuals also suffer from serious co-morbidities like diabetes and coronary or cerebrovascular disease. Circulatory dysfunction or dysvascular disease is the major cause for amputations in the United States (www.amputee-coalition.orf/fact_sheet/amp_stats_cause.html). Increasing sedentary lifestyles have lead to increased rates of diabetes which has significantly contributed to an increased number of amputations in recent years. The risk of amputation in a diabetic individual is 25 times higher than in the non-diabetic population. The level of amputation that is appropriate for an individual depends on the extent of damage to his/her tissues. Common amputations of the lower extremities in the dysvascular population include the transtibial and transfemoral amputations. The individual having a transtibial or below knee amputation, will be fitted with a prosthetic foot to assist with functional ambulation, while a person with a transfemoral amputation will require both a prosthetic foot and knee for ambulatory purposes. Currently dysvascular amputees are given prostheses based on the goal of returning them to a basic level of function focused primarily on stability. They are considered lower functioning walkers and are expected to use a slow and constant walking speed to ambulate around their homes and are not considered traditional community ambulators. Therefore, they are traditionally given standard mechanical knees which are considered safe, as they provide the ability for only simple single speed house-hold tasks. While this criterion does return the patient to function for basic Activities of Daily Living (ADLs) and walking at a single cadence, it does not empower the patient to counteract the previously existing co-morbidities. Dysvascular amputees tend to be less active predisposing them to a more sedentary lifestyle and exacerbating their risk factors. Their prostheses make them energy inefficient and use more energy for ADLs and functional walking. This causes early onset of fatigue, induces anxiety and fear of falling. Further, they are often depressed, lose motivation and curtail their community interaction. This raises the question if dysvascular amputees are further functionally limited by the prostheses traditionally given to them.

More recently, technology has been used to assist with return to function in the amputee population. Microprocessor (MP) controlled knees are among the technological innovations applied to prostheses to not only return amputees to a basic function, but also with a view to return them to their highest possible function. Over the years, clinical use has shown that traditional knees provide the ability to complete ADLs and basic functions like sit - stand. However, activities like negotiating stairs/steps, walking on uneven ground and self-correction during tripping; functions which reintegrate amputees into unlimited community ambulation and social reintegration require prosthetics which advanced functionality. The Otto Bock C-leg is a MP knee that allows the patient a greater level of control in swing and stance phases of gait. This enables the TF amputee to adjust the requirements of gait during dynamic walking like changing the speed of walking, going up and down stairs and inclines, walking on grass and uneven surfaces and crossing an obstacle. The C-leg has been traditionally given to patients who begin post-amputation rehabilitation at a higher level, but are more expensive than traditionally mechanical knees. In the contrary however, a European study that defined health outcomes in terms of quality-adjusted life year (QALY), indicated that the C-leg showed a QALY gain of €3218 per patient, makes it still financial viable keeping it mind its price tag.. The purpose of this study is to compare the traditional mechanical knee to the microprocessor knee (C-leg) in the dysvascular population. The study will specifically evaluate the potential of microprocessor knees to improve the quality of life in dysvascular transfemoral amputees. This includes identifying if the C-leg can increase the activity level to be classified at a higher level by the Medicare classification from K2 (lower level ambulators) to K3 (more proficient ambulators), along with increasing their social interaction in the community.

Eligibility criteria: Inclusion Criteria:

* Males or females with dysvascular transfemoral amputations
* 6 months or more post prosthetic fitting
* Homebound or limited community ambulators post amputation
* Ability to walk \> 50m in a 2 min walk test

Exclusion Criteria:

* Traumatic, cancer or genetic amputation
* Co-morbidity that completely prevents physical activity
* Significant skin lesions/ulcers on stump that prevent fitting of prosthesis
* Cognitive deficits or visual impairments that would impair their ability to give informed consent or to follow simple instructions during experiment

Primary outcomes:
measure: Change in Community Physical Activity as Measured by GPS
timeFrame: baseline, 1 month with mechanical knee, 1 month with microprocessor knee
Secondary outcomes:
measure: Change in 6 Minute Walk Test From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in 10 Meter Walk Test Gait Speed From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Amputee Mobility Predictor Score From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Berg Balance Score From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Timed Up and Go Test Time From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Four Square Step Test Time From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Modified Falls Efficacy Scale From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Community Participation Indicators From Baseline
timeFrame: After 3 month acclimation period to device
measure: Change in Prosthesis Evaluation Questionnaire (PEQ) From Baseline
timeFrame: After 3 month acclimation period to device
Other outcomes:
Locations:
city: Chicago
country: United States
facility: Rehabilitation Institute of Chicago, 345 E Superior St
state: Illinois
Study officials:
affiliation: Shirley Ryan AbilityLab
name: Arun Jayaraman, PT PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Theeven P, Hemmen B, Rings F, Meys G, Brink P, Smeets R, Seelen H. Functional added value of microprocessor-controlled knee joints in daily life performance of Medicare Functional Classification Level-2 amputees. J Rehabil Med. 2011 Oct;43(10):906-15. doi: 10.2340/16501977-0861.
citation: Jayaraman C, Mummidisetty CK, Albert MV, Lipschutz R, Hoppe-Ludwig S, Mathur G, Jayaraman A. Using a microprocessor knee (C-Leg) with appropriate foot transitioned individuals with dysvascular transfemoral amputations to higher performance levels: a longitudinal randomized clinical trial. J Neuroeng Rehabil. 2021 May 25;18(1):88. doi: 10.1186/s12984-021-00879-3.