Ignite Creation Date:
2025-12-25 @ 1:08 AM
Ignite Modification Date:
2025-12-25 @ 11:19 PM
Study NCT ID:
NCT00117793
Status:
COMPLETED
Last Update Posted:
2014-08-15
First Post:
2005-07-01
Is NOT Gene Therapy:
False
Has Adverse Events:
True
Brief Title:
Vacuum Suspension: Effects on Tissue Oxygenation, Activity and Fit
Sponsor:
Organization:
Raw JSON
{'hasResults': True, 'derivedSection': {'miscInfoModule': {'versionHolder': '2025-12-24'}, 'conditionBrowseModule': {'meshes': [{'id': 'D003920', 'term': 'Diabetes Mellitus'}, {'id': 'D007869', 'term': 'Leg Injuries'}, {'id': 'D000673', 'term': 'Amputation, Traumatic'}], 'ancestors': [{'id': 'D044882', 'term': 'Glucose Metabolism Disorders'}, {'id': 'D008659', 'term': 'Metabolic Diseases'}, {'id': 'D009750', 'term': 'Nutritional and Metabolic Diseases'}, {'id': 'D004700', 'term': 'Endocrine System Diseases'}, {'id': 'D014947', 'term': 'Wounds and Injuries'}]}}, 'resultsSection': {'moreInfoModule': {'pointOfContact': {'email': 'Glenn.Klute@va.gov', 'phone': '206-277-6724', 'title': 'Glenn K. Klute, PhD', 'organization': 'Dept. of Veterans Affairs, Rehabilitation Research & Development Service'}, 'certainAgreement': {'piSponsorEmployee': True}, 'limitationsAndCaveats': {'description': 'The small number of participants who completed the protocol precluded a statistical analysis on the secondary outcome measures.'}}, 'adverseEventsModule': {'eventGroups': [{'id': 'EG000', 'title': 'Entire Study Population', 'description': 'Includes participants randomized to receive PIN first and VASS first.', 'otherNumAtRisk': 17, 'otherNumAffected': 1, 'seriousNumAtRisk': 17, 'seriousNumAffected': 0}], 'otherEvents': [{'term': 'Prosthesis failure', 'notes': 'Socket fracture during routine activity preventing further use. Participant was wearing VASS at time of failure.', 'stats': [{'groupId': 'EG000', 'numAtRisk': 17, 'numEvents': 1, 'numAffected': 1}], 'organSystem': 'Injury, poisoning and procedural complications', 'assessmentType': 'NON_SYSTEMATIC_ASSESSMENT'}], 'frequencyThreshold': '5'}, 'outcomeMeasuresModule': {'outcomeMeasures': [{'type': 'PRIMARY', 'title': 'Limb Volume', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '0.68', 'spread': '.14', 'groupId': 'OG000'}, {'value': '0.72', 'spread': '.13', 'groupId': 'OG001'}]}]}], 'analyses': [{'pValue': '>0.05', 'groupIds': ['OG000', 'OG001'], 'ciPctValue': '95', 'pValueComment': 'Statistical significance was set a-priori at p \\< 0.05.', 'statisticalMethod': 'Mixed Models Analysis', 'nonInferiorityType': 'SUPERIORITY_OR_OTHER', 'statisticalComment': 'The effect of study limb on limb volume was analyzed using repeated measures one-way analyses of variance.', 'testedNonInferiority': False}], 'paramType': 'MEAN', 'timeFrame': 'Measurements were taken after wearing the study prostheses for three weeks', 'unitOfMeasure': 'liters', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}, {'type': 'PRIMARY', 'title': 'Activity Level', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '73', 'spread': '18', 'groupId': 'OG000'}, {'value': '38', 'spread': '9', 'groupId': 'OG001'}]}]}], 'analyses': [{'pValue': '=0.0056', 'groupIds': ['OG000', 'OG001'], 'ciPctValue': '95', 'pValueComment': 'Statistical significance was set a-priori at p \\< 0.05.', 'statisticalMethod': 'Mixed Models Analysis', 'nonInferiorityType': 'SUPERIORITY_OR_OTHER', 'statisticalComment': 'The effect of study limb on activity level was analyzed using repeated measures one-way analyses of variance.', 'testedNonInferiority': False}], 'paramType': 'MEAN', 'timeFrame': 'Two weeks', 'description': 'Total number of steps during a two week period ending in the fourth week for each study prosthesis (PIN and VASS).', 'unitOfMeasure': 'steps (in thousands)', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}, {'type': 'PRIMARY', 'title': 'Limb Pistoning', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '6', 'spread': '4', 'groupId': 'OG000'}, {'value': '1', 'spread': '3', 'groupId': 'OG001'}]}]}], 'analyses': [{'pValue': '=0.0021', 'groupIds': ['OG000', 'OG001'], 'ciPctValue': '95', 'pValueComment': 'Statistical significance was set a-priori at p \\< 0.05.', 'statisticalMethod': 'Mixed Models Analysis', 'nonInferiorityType': 'SUPERIORITY_OR_OTHER', 'statisticalComment': 'The effect of study limb on limb pistoning was analyzed using repeated measures one-way analyses of variance.', 'testedNonInferiority': False}], 'paramType': 'MEAN', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for three weeks', 'description': 'Limb pistoning is the change in the resultant distance between the prosthetic-side knee joint marker triad and the residual limb thigh triad measured using a 12-camera motion analysis system while subjects weighted and un-weighted their prosthesis standing in place.', 'unitOfMeasure': 'mm', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}, {'type': 'SECONDARY', 'title': 'Residual Limb Health (PEQ Scale)', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '90', 'spread': '5', 'groupId': 'OG000'}, {'value': '77', 'spread': '20', 'groupId': 'OG001'}]}]}], 'paramType': 'MEAN', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. The Residual Limb Health scale examines: sweat, smell, volume changes, rashes, ingrown hairs, and blisters. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., most healthful).', 'unitOfMeasure': 'units on a scale', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}, {'type': 'SECONDARY', 'title': 'Ambulation (PEQ Scale)', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '95', 'spread': '6', 'groupId': 'OG000'}, {'value': '67', 'spread': '22', 'groupId': 'OG001'}]}]}], 'paramType': 'MEAN', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. The Ambulation scale queries the ability to walk in general, in close spaces, on stairs and ramps, in urban environments, and on slippery surfaces. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., easiest to walk on).', 'unitOfMeasure': 'units on a scale', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}, {'type': 'SECONDARY', 'title': 'Frustration (PEQ Scale)', 'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'OG000'}, {'value': '5', 'groupId': 'OG001'}]}], 'groups': [{'id': 'OG000', 'title': 'PIN Suspension', 'description': 'A modified patellar tendon bearing socket with a pin lock suspension system (PIN)'}, {'id': 'OG001', 'title': 'VASS Suspension', 'description': 'A total surface bearing socket with a vacuum-assisted suspension system (VASS).'}], 'classes': [{'categories': [{'measurements': [{'value': '91', 'spread': '11', 'groupId': 'OG000'}, {'value': '43', 'spread': '29', 'groupId': 'OG001'}]}]}], 'paramType': 'MEAN', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. Frustration was assessed by frequency of occurrence and rating. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., least frustrating).', 'unitOfMeasure': 'units on a scale', 'dispersionType': 'Standard Deviation', 'reportingStatus': 'POSTED', 'populationDescription': 'The number of participants for analysis is equal to the number of participants who completed the study protocol.'}]}, 'participantFlowModule': {'groups': [{'id': 'FG000', 'title': 'Entire Study Population', 'description': 'This is a randomized cross-over study. Each participant wore both study prostheses: (1) a total surface bearing socket with a vacuum-assisted suspension system (VASS) and (2) a modified patellar tendon bearing socket with a pin lock suspension system (PIN).\n\nSubjects were randomized, provided with one of two study prostheses, and asked to wear it for three weeks. Data was then collected during laboratory visit one, and, following one more week of wearing the first study prosthesis, during laboratory visit two. Participants were then provided with the second study intervention and asked to wear it for three weeks. Data was then collected during laboratory visit three, and, following one more week of wearing the second study intervention, during laboratory visit four.\n\nData was not collected on the order in which participants received each study intervention'}], 'periods': [{'title': 'Overall Study', 'milestones': [{'type': 'STARTED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '17'}]}, {'type': 'COMPLETED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '5'}]}, {'type': 'NOT COMPLETED', 'achievements': [{'groupId': 'FG000', 'numSubjects': '12'}]}], 'dropWithdraws': [{'type': 'Withdrawal by Subject', 'reasons': [{'groupId': 'FG000', 'numSubjects': '12'}]}]}], 'recruitmentDetails': 'Recruitment for this study was conducted at the VA Puget Sound Health Care System (Seattle VA hospital). Recruitment began on March 28, 2007. The study was closed to enrollment on March 30, 2012.', 'preAssignmentDetails': "The prostheses used in this study were built and aligned by a certified and licensed prosthetist prior to beginning starting the protocol. 20 individuals gave informed consent but 3 withdrew prior to starting: 1 had contralateral knee surgery, 1 became a bi-lateral amputee, and 1 was withdrawn by the participant's physician."}, 'baselineCharacteristicsModule': {'denoms': [{'units': 'Participants', 'counts': [{'value': '5', 'groupId': 'BG000'}]}], 'groups': [{'id': 'BG000', 'title': 'Entire Study Population', 'description': 'Includes participants randomized to receive PIN first and VASS first.'}], 'measures': [{'title': 'Age, Categorical', 'classes': [{'categories': [{'title': '<=18 years', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Between 18 and 65 years', 'measurements': [{'value': '5', 'groupId': 'BG000'}]}, {'title': '>=65 years', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}]}], 'paramType': 'COUNT_OF_PARTICIPANTS', 'unitOfMeasure': 'Participants'}, {'title': 'Age, Continuous', 'classes': [{'categories': [{'measurements': [{'value': '56', 'spread': '9', 'groupId': 'BG000'}]}]}], 'paramType': 'MEAN', 'unitOfMeasure': 'years', 'dispersionType': 'STANDARD_DEVIATION'}, {'title': 'Sex: Female, Male', 'classes': [{'categories': [{'title': 'Female', 'measurements': [{'value': '0', 'groupId': 'BG000'}]}, {'title': 'Male', 'measurements': [{'value': '5', 'groupId': 'BG000'}]}]}], 'paramType': 'COUNT_OF_PARTICIPANTS', 'unitOfMeasure': 'Participants'}, {'title': 'Amputation etiology', 'classes': [{'title': 'Diabetic', 'categories': [{'measurements': [{'value': '1', 'groupId': 'BG000'}]}]}, {'title': 'Traumatic', 'categories': [{'measurements': [{'value': '4', 'groupId': 'BG000'}]}]}], 'paramType': 'NUMBER', 'unitOfMeasure': 'Participants'}, {'title': 'Years post-amputation', 'classes': [{'categories': [{'measurements': [{'value': '13', 'spread': '15', 'groupId': 'BG000'}]}]}], 'paramType': 'MEAN', 'unitOfMeasure': 'Years', 'dispersionType': 'STANDARD_DEVIATION'}, {'title': 'Weight', 'classes': [{'categories': [{'measurements': [{'value': '84', 'spread': '11', 'groupId': 'BG000'}]}]}], 'paramType': 'MEAN', 'unitOfMeasure': 'kg', 'dispersionType': 'STANDARD_DEVIATION'}, {'title': 'Height', 'classes': [{'categories': [{'measurements': [{'value': '1.78', 'spread': '0.11', 'groupId': 'BG000'}]}]}], 'paramType': 'MEAN', 'unitOfMeasure': 'm', 'dispersionType': 'STANDARD_DEVIATION'}], 'populationDescription': 'The sample population descriptors are based on the participants who completed the study protocol.'}}, 'protocolSection': {'designModule': {'phases': ['NA'], 'studyType': 'INTERVENTIONAL', 'designInfo': {'allocation': 'RANDOMIZED', 'maskingInfo': {'masking': 'SINGLE', 'whoMasked': ['PARTICIPANT']}, 'primaryPurpose': 'TREATMENT', 'interventionModel': 'CROSSOVER'}, 'enrollmentInfo': {'type': 'ACTUAL', 'count': 20}}, 'statusModule': {'overallStatus': 'COMPLETED', 'startDateStruct': {'date': '2005-08'}, 'expandedAccessInfo': {'hasExpandedAccess': False}, 'statusVerifiedDate': '2014-07', 'completionDateStruct': {'date': '2008-09', 'type': 'ACTUAL'}, 'lastUpdateSubmitDate': '2014-07-28', 'studyFirstSubmitDate': '2005-07-01', 'resultsFirstSubmitDate': '2013-10-24', 'studyFirstSubmitQcDate': '2005-07-07', 'lastUpdatePostDateStruct': {'date': '2014-08-15', 'type': 'ESTIMATED'}, 'resultsFirstSubmitQcDate': '2014-07-28', 'studyFirstPostDateStruct': {'date': '2005-07-08', 'type': 'ESTIMATED'}, 'resultsFirstPostDateStruct': {'date': '2014-08-15', 'type': 'ESTIMATED'}, 'primaryCompletionDateStruct': {'date': '2008-09', 'type': 'ACTUAL'}}, 'outcomesModule': {'primaryOutcomes': [{'measure': 'Limb Volume', 'timeFrame': 'Measurements were taken after wearing the study prostheses for three weeks'}, {'measure': 'Activity Level', 'timeFrame': 'Two weeks', 'description': 'Total number of steps during a two week period ending in the fourth week for each study prosthesis (PIN and VASS).'}, {'measure': 'Limb Pistoning', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for three weeks', 'description': 'Limb pistoning is the change in the resultant distance between the prosthetic-side knee joint marker triad and the residual limb thigh triad measured using a 12-camera motion analysis system while subjects weighted and un-weighted their prosthesis standing in place.'}], 'secondaryOutcomes': [{'measure': 'Residual Limb Health (PEQ Scale)', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. The Residual Limb Health scale examines: sweat, smell, volume changes, rashes, ingrown hairs, and blisters. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., most healthful).'}, {'measure': 'Ambulation (PEQ Scale)', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. The Ambulation scale queries the ability to walk in general, in close spaces, on stairs and ramps, in urban environments, and on slippery surfaces. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., easiest to walk on).'}, {'measure': 'Frustration (PEQ Scale)', 'timeFrame': 'Measurements were taken after wearing the study prosthesis for four weeks', 'description': 'Qualitative differences between the study limbs were assessed using the Prosthesis Evaluation Questionnaire (PEQ). This standardized, self-report instrument is specific to persons with lower limb amputations and is used to evaluate prosthetic care with regard to prescription and prosthesis-related quality of life. Frustration was assessed by frequency of occurrence and rating. The scale is scored from 0 to 100 where 100 indicates the best outcome (i.e., least frustrating).'}]}, 'oversightModule': {'oversightHasDmc': False}, 'conditionsModule': {'keywords': ['Amputee', 'Artificial limbs', 'Gait', 'Walking'], 'conditions': ['Amputation', 'Diabetes', 'Leg Injuries', 'Traumatic Amputations']}, 'referencesModule': {'references': [{'pmid': '21963124', 'type': 'DERIVED', 'citation': 'Klute GK, Berge JS, Biggs W, Pongnumkul S, Popovic Z, Curless B. Vacuum-assisted socket suspension compared with pin suspension for lower extremity amputees: effect on fit, activity, and limb volume. Arch Phys Med Rehabil. 2011 Oct;92(10):1570-5. doi: 10.1016/j.apmr.2011.05.019.'}]}, 'descriptionModule': {'briefSummary': 'The fit of the residual limb within a prosthetic socket is a primary concern for many amputees. A poor fit can lead to skin irritation, tissue breakdown, and pain. Further, amputees with diabetes or vascular dysfunction often have difficulty maintaining healthy residual limb tissue; a condition that could be mitigated by the application of negative pressure (i.e., vacuum suspension). The aim of this research is to characterize the residual limb response to a vacuum suspension system and to measure prosthetic performance in comparison to a typical suction suspension system.\n\nThe proposed research plan involves two sets of human subject experiments: (1) prospective, randomized cross-over study to quantify performance of a vacuum suspension system as compared to a total surface bearing suction socket in terms of pistoning, maintaining limb volume, step counts, and subjective measures of fit and (2) measurement of transcutaneous oxygen tension as a function of vacuum pressure.', 'detailedDescription': 'A proper fitting prosthetic socket provides the amputee with a comfortable system allowing them to pursue many of their desired vocational and recreational goals. Unfortunately, many amputees live with an ill-fitting socket and can experience limb pistoning within the socket, which in turn may result in skin irritation, tissue breakdown, discomfort, and a reduction in activity. One of the key factors affecting fit is intraday residual limb volume changes. For an amputee with dysvascular conditions, the implications of a poor fitting socket are exacerbated by poor circulation, reduced healing potential and the compressive forces exerted by their prosthesis.\n\nVacuum suspension systems may have the potential to alleviate these conditions for healthy and dysvascular amputees. The purported benefits of vacuum suspension systems include, but are not limited to: improved suspension (reduction in the amount of pistoning), maintenance of limb volume throughout the day, and increased tissue oxygenation to the residual limb.\n\nOur first objective is to characterize performance, as related to socket fit, of a vacuum suspension system using objective and subjective measures. We will do this by conducting a within-subject experiment to measure pistoning in three dimensions while walking, overall and regional changes in limb volume before and after a thirty-minute treadmill walk, mobility (step counts) and the perception of socket fit (questionnaire) as a function of prosthetic prescription (vacuum suspension system vs. total surface bearing suction socket).\n\nOur second objective is to determine the effect of pressures within a prosthetic socket on residual limb transcutaneous oxygen tension (tcpO2) levels. We will conduct laboratory-based, in situ testing to determine how the transcutaneous oxygen tension levels, at six sites on the residual limb, respond to pressures simulating those within a vacuum suspension system and a total surface bearing suction socket.\n\nThe proposed research will allow us to understand how suspension systems influence prosthetic socket fit and residual limb tissue health and to formulate a knowledge base on two suspension systems providing prosthetists and clinicians the objective data to make better prescription decisions. In addition, the methods utilized in this study (e.g., a residual limb limb volume scanner and assessing dynamic pistoning) can be used to study current and novel suspension systems, liners, and prosthetic socket designs to provide a standard for comparison.'}, 'eligibilityModule': {'sex': 'ALL', 'stdAges': ['ADULT', 'OLDER_ADULT'], 'maximumAge': '70 Years', 'minimumAge': '18 Years', 'healthyVolunteers': True, 'eligibilityCriteria': 'Inclusion Criteria:\n\n* Over 18 and less than 70 years of age,\n* Have a below knee amputation involving only one side,\n* If the cause of amputation was for traumatic reasons and do not have diabetes or a vascular condition, the amputation must have occurred at least six months ago and the potential subject must have worn a prosthesis for at least four months,\n* If the cause of amputation was for diabetes or vascular reasons, the potential subject must have been fit with a prosthesis and have worn it for at least one year,\n* Wear the prosthesis for at least 6 hours a day,\n* Able to walk without a cane, crutches, or a walker,\n* Are moderately active enough to walk at a steady pace for at least 30 minutes.\n\nExclusion Criteria:\n\n* Have pain in legs or any condition that interferes with walking.\n* Have an ulcer on the residual limb,\n* If potential subject had an amputation because of a tumor or an infection, no longer have an active tumor or undergoing treatment for a tumor,\n* Have fallen within the last 3 months.'}, 'identificationModule': {'nctId': 'NCT00117793', 'briefTitle': 'Vacuum Suspension: Effects on Tissue Oxygenation, Activity and Fit', 'organization': {'class': 'FED', 'fullName': 'VA Office of Research and Development'}, 'officialTitle': 'Vacuum Suspension: Effects on Tissue Oxygenation, Activity and Fit', 'orgStudyIdInfo': {'id': 'A3666'}}, 'armsInterventionsModule': {'armGroups': [{'type': 'ACTIVE_COMPARATOR', 'label': 'Arm 1', 'description': 'Current clinical practice', 'interventionNames': ['Device: Total Surface Bearing Suction Socket']}, {'type': 'EXPERIMENTAL', 'label': 'Arm 2', 'description': 'Novel socket system', 'interventionNames': ['Device: Vacuum assisted socket system']}], 'interventions': [{'name': 'Total Surface Bearing Suction Socket', 'type': 'DEVICE', 'description': 'Current clinical practice', 'armGroupLabels': ['Arm 1']}, {'name': 'Vacuum assisted socket system', 'type': 'DEVICE', 'description': 'Novel socket system', 'armGroupLabels': ['Arm 2']}]}, 'contactsLocationsModule': {'locations': [{'zip': '98108', 'city': 'Seattle', 'state': 'Washington', 'country': 'United States', 'facility': 'VA Puget Sound Health Care System, Seattle', 'geoPoint': {'lat': 47.60621, 'lon': -122.33207}}], 'overallOfficials': [{'name': 'Glenn K. Klute, PhD', 'role': 'PRINCIPAL_INVESTIGATOR', 'affiliation': 'VA Puget Sound Health Care System, Seattle'}]}, 'sponsorCollaboratorsModule': {'leadSponsor': {'name': 'US Department of Veterans Affairs', 'class': 'FED'}, 'responsibleParty': {'type': 'SPONSOR'}}}}