Clinical trial NCT05662982: Sub-Ischial Socket for Transfemoral Amputation and Lower Mobility
Official title: Evaluation of the Northwestern University Subischial Socket for Persons With Transfemoral Amputation and Lower Mobility Levels
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Transfemoral Amputation
Keywords: prosthesis
prosthetic socket
Lead sponsor: University of Washington
Sponsor class: OTHER
Collaborators: name: Congressionally Directed Medical Research Programs
First posted: 2022-12-23
Enrollment: 115
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Two independent groups will be assessed longitudinally over 40 weeks: one group will be assessed using only the standard of care ischial containment socket and the other group will receive the subischial socket.
Primary purpose: TREATMENT

Brief summary: The objective of this trial is to assess use and benefits of the subischial socket for persons with transfemoral amputation and lower mobility levels. Specifically, the investigators will evaluate whether the subischial socket improves comfort, socket wear time, mobility, participation, quality of life and satisfaction with device than the standard-of-care ischial containment socket.

Detailed description: Prosthetic sockets that are currently used by persons with above-the-knee amputation (AKA) fit intimately with the thigh and pelvis, limiting hip motion and causing discomfort. Socket comfort while standing and sitting is of great importance to persons with lower limb amputation. Yet discomfort while sitting has been reported in 44% of persons with AKA. In those with AKA who are more sedentary, clinical observation indicates that socket discomfort in sitting results in less prosthesis wear time and less mobility with the prosthesis. Based on these observations, the investigators propose that improving socket comfort in persons with AKA who have lower mobility will increase the time spent wearing the socket, which will in turn increase mobility, and in turn again improve satisfaction with the prosthesis and overall quality-of-life. A new prosthetic socket design, the sub-ischial socket, which eliminates contact with the pelvis, has been developed with the intent of improving comfort and hip motion in people with AKA. In particular, sitting comfort has been highlighted as an advantage of this new socket design by early users. Therefore, the objective of this project is to assess use and benefits of the sub-ischial socket for persons with AKA and lower mobility levels. The investigators will evaluate whether the sub-ischial socket is more comfortable, improves prosthesis wear time, mobility, participation in society, satisfaction with device, skin-related quality-of-life, and health-related quality of life compared to the current standard-of-care socket design in persons with AKA and lower mobility levels. If a participant is eligible and enrolled into this study, participation would last about 10 months and would involve up to 8 in-person visits (for individuals receiving a new sub-ischial socket). Individuals receiving a new sub-ischial socket will also be asked to wear a step counter and temperature sensor and complete 11 remote survey assessments spread over the 10-month period of the study. Data will also be collected from a reference group of participants with transfemoral amputation and lower mobility levels who will not receive a sub-ischial socket. These participants will be assessed while wearing their clinically-provided, standard-of-care ischial containment socket. These participants will complete 8 remote survey assessments over a 10-month period.

Eligibility criteria: Inclusion Criteria:

1. Speak and read English;
2. Provision of signed and dated informed consent form;
3. Stated willingness to comply with all study procedures and availability for the duration of the study;
4. All sexes and genders age 18 years and older;
5. Have a unilateral transfemoral or knee disarticulation amputation and have used a prosthesis for 1 year or more;
6. Be classified by their prosthetist as being a Medicare Functional Classification Level of K2 (limited community ambulator);
7. Have never worn a sub-ischial socket;
8. Current IC socket and prosthesis must be well fitting and maintained; current socket must have pelvic weightbearing and/or containment;
9. Participant has no plans to change the knee or foot in the next 10 months;
10. Willingness to adhere to the monitoring and new socket regimen;
11. Have sufficient upper limb function to don liner and change sensors;
12. Access to necessary resources for participating in the study (i.e., computer, smartphone, internet access, telephone):
13. Be a Veteran (VA site only).

Exclusion Criteria (intervention group only):

1. Have a femoral length \<5 inches;
2. Have a known silicone allergy;
3. Are unable to don or tolerate wearing a compressive liner;
4. Loss of metatarsal heads on contralateral limb;
5. Active malignancy;
6. Pregnancy;
7. Polytrauma that affects functional ability beyond that of a unilateral transfemoral amputation.

Primary outcomes:
measure: Change in Socket Comfort Score (SCS)
timeFrame: Change from week 12 to week 24 compared between Intervention and Reference Groups.
Secondary outcomes:
measure: Temperature sensor
timeFrame: Intervention group only: Baseline period weeks 0-12; Intervention period weeks 0-24.
measure: Step counter
timeFrame: Intervention group only: Baseline period weeks 0-4; Intervention period weeks 0-4 and 20-24.
measure: Prosthesis Limb Users Survey-Mobility (PLUS-M)
timeFrame: All participants: Baseline period weeks 0, 4, 8, 12; Intervention group: Intervention period weeks 4, 8, 12, 16, 20, 24; Reference group: Monitoring period weeks 4, 12, 20, 24.
measure: Activities-specific Balance Confidence (ABC) Scale
timeFrame: All participants: Baseline period weeks 0, 4, 8, 12; Intervention group: Intervention period weeks 4, 8, 12, 16, 20, 24; Reference group: Monitoring period weeks 4, 12, 20, 24.
measure: Prosthesis Evaluation Questionnaire (PEQ) Residual Limb Health
timeFrame: All participants: Baseline period weeks 0, 4, 8, 12; Intervention group: Intervention period weeks 0, 4, 8, 12, 16, 20, 24; Reference group: Monitoring period weeks 4, 12, 20, 24.
measure: Roland-Morris Disability Questionnaire (RMDQ)
timeFrame: All participants: Baseline period weeks 0, 4, 8, 12; Intervention group: Intervention period weeks 0, 4, 8, 12, 16, 20, 24; Reference group: Monitoring period weeks 4, 12, 20, 24.
measure: Patient-Reported Outcomes Measurement Information System (PROMIS) Ability to Participate in Social Roles
timeFrame: All participants: Baseline period weeks 0, 12; Intervention/Monitoring period weeks 4, 12, 24.
measure: Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health-10
timeFrame: All participants: Baseline period weeks 0, 12; Intervention/Monitoring period weeks 4, 12, 24.
measure: Patient-Reported Outcomes Measurement Information System (PROMIS) Depression
timeFrame: All participants: Baseline period weeks 0, 12; Intervention/Monitoring period weeks 4, 12, 24.
measure: Orthotic and Prosthetic Users' Survey Satisfaction with Device (OPUS-SwD)
timeFrame: All participants: Baseline period weeks 0, 12; Intervention/Monitoring period weeks 4, 12, 24.
measure: Charlson Comorbidity Index (CCI)
timeFrame: All participants: Baseline period week 0; Intervention/Monitoring period weeks 4, 24.
measure: Falls
timeFrame: All participants: Baseline period weeks 0, 4, 8, 12; Intervention group: Intervention period weeks 0, 4, 8, 12, 16, 20, 24; Reference group: Monitoring period weeks 4, 12, 20, 24.
Other outcomes:
measure: Amputee Mobility Predictor with Prosthesis (AMP-Pro)
timeFrame: Intervention group only: Baseline period week 0; Intervention period weeks 0, 20.
measure: International Society for Prosthetics and Orthotics (ISPO) Minimum Data Set for lower-limb prosthesis users involved Research Studies
timeFrame: Intervention group: Baseline period week 0; Intervention period week 0. Reference Group: Baseline period week 0.
Locations:
city: Minneapolis
country: United States
facility: Minneapolis VA Health Care System
state: Minnesota
city: Houston
country: United States
facility: Hanger Institute for Clinical Research and Education
state: Texas
city: Seattle
country: United States
facility: University of Washington
state: Washington
Study officials:
affiliation: University of Washington
name: Stefania Fatone, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Fatone S, Caldwell R. Northwestern University Flexible Subischial Vacuum Socket for persons with transfemoral amputation-Part 1: Description of technique. Prosthet Orthot Int. 2017 Jun;41(3):237-245. doi: 10.1177/0309364616685229. Epub 2017 Jan 17.
citation: Caldwell R, Fatone S. Technique modifications for a suction suspension version of the Northwestern University Flexible Sub-Ischial Vacuum socket: The Northwestern University Flexible Sub-Ischial Suction socket. Prosthet Orthot Int. 2019 Apr;43(2):233-239. doi: 10.1177/0309364618798869. Epub 2018 Sep 17.
citation: Fatone S, Caldwell R, Angelico J, Stine R, Kim KY, Gard S, Oros M. Comparison of Ischial Containment and Subischial Sockets on Comfort, Function, Quality of Life, and Satisfaction With Device in Persons With Unilateral Transfemoral Amputation: A Randomized Crossover Trial. Arch Phys Med Rehabil. 2021 Nov;102(11):2063-2073.e2. doi: 10.1016/j.apmr.2021.05.016. Epub 2021 Jun 29.
citation: Fatone S, Stine R, Caldwell R, Angelico J, Gard SA, Oros M, Major MJ. Comparison of Ischial Containment and Subischial Sockets Effect on Gait Biomechanics in People With Transfemoral Amputation: A Randomized Crossover Trial. Arch Phys Med Rehabil. 2022 Aug;103(8):1515-1523. doi: 10.1016/j.apmr.2022.02.013. Epub 2022 Mar 13.