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York Study of Unloading Shoes for Vascular Intermittent Claudication (YORVIC)

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ClinicalTrials.gov Identifier: NCT02505503
Recruitment Status : Completed
First Posted : July 22, 2015
Last Update Posted : September 14, 2016
Sponsor:
Collaborators:
University of York
York St John University
University of Salford
Information provided by (Responsible Party):
York Teaching Hospitals NHS Foundation Trust

Brief Summary:

Some people experience a cramp-like leg pain during walking that is relieved only by rest. This is called intermittent claudication (IC) and it is a common symptom of peripheral arterial disease. Patients with IC struggle to walk, which in turn lowers their quality of life.

The intensity of IC pain experienced during walking depends on several factors, including the type of footwear worn. For example, non-supportive shoes may make the calf muscles work harder during walking, leading to earlier and more-severe symptoms of IC.

A member of the research team has developed a shoe that reduces the work done by the lower-leg muscles during walking. Preliminary data indicate that, when wearing these "unloading shoes", people with IC were able to walk further without pain as compared with when wearing a normal pair of shoes. The current project aims to provide further information on the usefulness and acceptability of these shoes.

Forty people with IC will complete a set of three walking tests on two separate occasions; once whilst wearing the unloading shoes, and once whilst wearing some normal shoes. The participants will then be given a pair of unloading or normal shoes to wear for two weeks, after which we will collect information on how acceptable the shoes were to wear via a survey of all participants and one-to-one interviews with a subset of participants.


Condition or disease Intervention/treatment Phase
Intermittent Claudication Peripheral Arterial Disease Device: Unloading shoes Device: Unadapted control shoe Not Applicable

  Show Detailed Description

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 38 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Randomised Crossover Study With Nested Qualitative Component Investigating the Clinical Efficacy and Acceptability of Unloading Shoes in Patients With Intermittent Claudication Due to Peripheral Arterial Disease
Study Start Date : July 2015
Actual Primary Completion Date : August 2016
Actual Study Completion Date : September 2016

Resource links provided by the National Library of Medicine


Arm Intervention/treatment
Active Comparator: Unloading shoes
The unloading shoe will be a trainer-type shoe with a cosmetically-shaped rocker sole. The sole will have three circular curves whose arc centres are positioned at the anatomical ankle, hip and knee respectively; assuming a vertical lower limb. This is designed to influence the line of action of the ground reaction force to pass close to the anatomical joint centres and so reduce the moments needed to be generated for ambulation by the muscles acting across those joints in the lower limb. Additionally it is designed to place the ankle into a relatively plantarflexed position where the ankle plantarflexors use less energy than for instance when placed in dorsiflexion.
Device: Unloading shoes
The unloading shoe will be a trainer-type shoe with a rocker sole incorporated. The sole is designed to influence the line of action of the ground reaction force to pass close to the anatomical joint centres and so reduce the moments needed to be generated for ambulation by the muscles acting across those joints in the lower limb. Additionally it is designed to place the ankle into a relatively plantarflexed position where the ankle plantarflexors use less energy than for instance when placed in dorsiflexion.

Device: Unadapted control shoe
During the control condition assessments, participants wear a pair of appropriately-sized shoes, which are similar in appearance to the unloading shoes, but do not contain the altered sole.

Placebo Comparator: Unadapted control shoes
The control shoes will be similar in appearance to the unloading shoes, but they will not contain the altered sole.
Device: Unloading shoes
The unloading shoe will be a trainer-type shoe with a rocker sole incorporated. The sole is designed to influence the line of action of the ground reaction force to pass close to the anatomical joint centres and so reduce the moments needed to be generated for ambulation by the muscles acting across those joints in the lower limb. Additionally it is designed to place the ankle into a relatively plantarflexed position where the ankle plantarflexors use less energy than for instance when placed in dorsiflexion.

Device: Unadapted control shoe
During the control condition assessments, participants wear a pair of appropriately-sized shoes, which are similar in appearance to the unloading shoes, but do not contain the altered sole.




Primary Outcome Measures :
  1. Total distance walked during 6-minute walk test [ Time Frame: Measured 40 minutes after putting on the intervention or control shoes ]
    Following a rest period of at least 20 minutes, participants will complete a 6-minute walk test in which they will be instructed to walk as far as possible within 6 minutes. A straight 30-m course will be used and the distance walked recorded.


Secondary Outcome Measures :
  1. Pain-free walking distance during usual-pace walking [ Time Frame: Measured 20 minutes after putting on the intervention or control shoes ]
    Following a rest period of at least 20 minutes, participants will be invited to walk at their usual walking speed along a straight 30-m course. Participants will be instructed to indicate the point where they first experience claudication pain. The distance walked up until this point will be recorded.

  2. Walking speed [ Time Frame: Measured 60 minutes after putting on the intervention or control shoes ]
    This variable will be assessed during self-paced walking.

  3. Step length [ Time Frame: Measured 60 minutes after putting on the intervention or control shoes ]
    This variable will be assessed during self-paced walking.

  4. Step cadence [ Time Frame: Measured 60 minutes after putting on the intervention or control shoes ]
    This variable will be assessed during self-paced walking.

  5. Muscle activation [ Time Frame: Measured 60 minutes after putting on the intervention or control shoes ]
    Electromyography will be used to observe when during the gait cycle of self-paced walking the calf muscles are activated. This will allow the investigators to determine the effectiveness of the unloading shoes in altering calf muscle activity.

  6. Joint moments [ Time Frame: Measured 60 minutes after putting on the intervention or control shoes ]
    An infrared camera system and force platform will be used to assess external moments at the ankle, knee and hip.


Other Outcome Measures:
  1. Adverse events / adverse device effects [ Time Frame: Participants will be followed for the duration of their study involvement, an expected average of 5 weeks. ]
    For the purpose of this study the adverse events that will be recorded are those that may occur as a result of performing any of the study assessments (e.g. walking tests), or the use of the study shoes (i.e. the investigational device).



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Ages Eligible for Study:   16 Years and older   (Child, Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Aged ≥16 years with intermittent claudication due to peripheral arterial disease
  • Resting ankle-brachial index ≤0.9 and/or imaging evidence of peripheral arterial disease
  • Stable symptoms for at least 3 months (assessed via self-report)
  • Pain-free walking distance <250 m on 6-minute walk test
  • Ambulation that is limited primarily by calf claudication on 6-minute walk test
  • Able to provide written informed consent
  • Able to read and speak English

Exclusion Criteria:

  • Absolute contraindications to exercise testing as defined by the American College of Sports Medicine
  • Critical limb ischemia
  • Function is uniquely impaired, e.g. vascular amputees
  • Co-morbidities that limit walking to a greater extent than intermittent claudication (e.g. severe arthritis)
  • Ambulation limited by claudication in regions other than the calf
  • Current or previous (within 6 months) use of shoe inserts, knee or ankle braces or customised shoes prescribed by a health professional
  • Ankle/foot pathology/pain on either side
  • "High-risk" foot (e.g. significant peripheral neuropathy, foot deformity, history of foot ulceration), assessed by a vascular specialist (Registrar or Consultant) or podiatrist

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02505503


Locations
United Kingdom
York St John University
York, North Yorkshire, United Kingdom, YO31 7EX
York Teaching Hospital NHS Foundation Trust
York, North Yorkshire, United Kingdom, YO31 8HE
Sponsors and Collaborators
York Teaching Hospitals NHS Foundation Trust
University of York
York St John University
University of Salford
Investigators
Principal Investigator: Garry Tew, PhD University of York

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: York Teaching Hospitals NHS Foundation Trust
ClinicalTrials.gov Identifier: NCT02505503     History of Changes
Other Study ID Numbers: YOR - A02382
First Posted: July 22, 2015    Key Record Dates
Last Update Posted: September 14, 2016
Last Verified: September 2016

Keywords provided by York Teaching Hospitals NHS Foundation Trust:
Claudication
Footwear
Shoes
Walking capacity
Walking distance

Additional relevant MeSH terms:
Peripheral Arterial Disease
Peripheral Vascular Diseases
Intermittent Claudication
Atherosclerosis
Arteriosclerosis
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases
Signs and Symptoms