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Trial registered on ANZCTR


Registration number
ACTRN12617001098325
Ethics application status
Approved
Date submitted
27/07/2017
Date registered
28/07/2017
Date last updated
13/04/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
Footwear for self-managing knee osteoarthritis symptoms: the Footstep Trial
Scientific title
Footwear for self-managing knee osteoarthritis symptoms: the Footstep Trial
Secondary ID [1] 291855 0
none
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Knee osteoarthritis 303114 0
Condition category
Condition code
Musculoskeletal 302570 302570 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This comparative effectiveness trial will compare two different classes of footwear:

Flat flexible shoes- selected from commercially available footwear, that fulfill previously published criteria for flat flexible shoes (Paterson et al, 2017, Osteoarthritis & Cartilage). These criteria are: 1) heel height of less than 15mm; 2) shoe pitch of less than 10mm; 3) absence of arch support or motion control; 4) have "minimal" rigidity (Barton et al. 2009, J Foot Ankle Res); and 5) weigh 200g or less (+/-10%). Measurements are based on a size 9 US Men's and size 9 US Women's. Participants in this group will choose two pairs of shoes from a selection of available shoes that fulfil the above criteria. As footwear manufacturers frequently change shoe models from season to season and year to year, we expect that shoes readily available at trial commencement will cease to be available during the course of the trial, or will be relaunched/rebranded with a different shoe name. In such instances, shoes will be replaced by a similar pair of commercially available shoes that fulfil the listed criteria.

Stable supportive shoes- selected from commercially available footwear, that fulfil previously published criteria for stable supportive shoes (Paterson et al, 2017,Osteoarthritis & Cartilage). These criteria are: 1) heel height of greater than 30mm; 2) shoe pitch of greater than 10mm; 3) presence of arch support or motion control; 4) have "rigid" rigidity (Barton et al. 2009, J Foot Ankle Res); and 5) weigh more than 300g (+/-10%). Measurements are based on a size 9 US Men's and size 9 US Women's. Participants in this group will choose two pairs of shoes from a selection of available shoes that fulfil the above criteria. As footwear manufacturers frequently change shoe models from season to season and year to year, we expect that shoes readily available at trial commencement will cease to be available during the course of the trial, or will be relaunched/rebranded with a different shoe name. In such instances, shoes will be replaced by a similar pair of commercially available shoes that fulfil the listed criteria.

The shoes will be provided at the University of Melbourne Human Movement Laboratory by one of the researchers experienced in the fitting shoes for participants in a randomized controlled trial. Participants will be asked to wear any combination of their 2 pairs of study shoes for at least 6 hours per day for the study duration of 6 months.

Participants will be provided with an information sheet regarding how to get used to wearing the shoes and will also complete a log book once per month where they will record the number of hours each day they wore each pair of their study shoes for a one week period (the fourth week of the month).
Intervention code [1] 297970 0
Treatment: Other
Comparator / control treatment
We are comparing the effects of the two footwear classes described under “intervention”.
Control group
Active

Outcomes
Primary outcome [1] 301991 0
Severity of knee pain while walking

Scored on an 11-point numerical rating scale (NRS) for average overall pain on walking in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [1] 301991 0
Baseline, and 6 months after randomization
Primary outcome [2] 301992 0
Physical function subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).

Scored using 17 questions regarding knee function in the last week, with Likert response options ranging from None to Extreme. WOMAC scores will be extracted from the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire, which contains the WOMAC questions. Total score ranges from 0 to 68; higher scores indicate worse function.
Timepoint [2] 301992 0
Baseline, and 6 months after randomization
Secondary outcome [1] 334460 0
Knee injury and Osteoarthritis Outcome Score (KOOS) pain subscale.

Scored using 9 questions about knee pain experienced in the last week, with Likert response options ranging from None to Extreme. Scores range from 0 to 100; lower scores indicate worse pain.
Timepoint [1] 334460 0
Baseline, and 6 months after randomization
Secondary outcome [2] 334461 0
KOOS sport and recreation subscale.

Scored using 5 questions about function with sport and recreational activities in the last week, with Likert response options ranging from None to Extreme. Scores range from 0 to 100; lower scores indicate worse function.
Timepoint [2] 334461 0
Baseline, and 6 months after randomization
Secondary outcome [3] 334462 0
KOOS quality of life subscale.

Scored using 4 questions about knee related quality of life experienced in the last week, with 5 Likert response options for each question. Scores range from 0 to 100; lower scores indicate worse quality of life.
Timepoint [3] 334462 0
Baseline, and 6 months after randomization
Secondary outcome [4] 334463 0
KOOS patellofemoral pain and OA subscale.

Scored using 11 questions about knee pain and function experienced in the last week, with 5 Likert response options for each question. Scores range from 0 to 100; lower scores indicate worse patellofemoral symptoms.
Timepoint [4] 334463 0
Baseline, and 6 months after randomization
Secondary outcome [5] 334464 0
Overall knee pain severity,

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [5] 334464 0
Baseline, and 6 months after randomization
Secondary outcome [6] 334466 0
Quality of life

Scored using the 20-item Assessment of Quality of Life II Instrument (AQOL) 6D version, which covers the topics of Independent Living, Relationships, Mental Health, Coping, Pain and Senses to come up with one overall value representing quality of life. Total score ranges from -0.04 to 1.00; higher scores indicate better quality of life.
Timepoint [6] 334466 0
Baseline, and 6 months after randomization
Secondary outcome [7] 334468 0
Physical Activity Scale for the Elderly

A self-reported assessment of physical activity, covering occupational, household and leisure items over the past week with one overall value representing physical activity level. Total score ranges from 0 to 400+; higher scores indicate greater activity.
Timepoint [7] 334468 0
Baseline, and 6 months after randomization
Secondary outcome [8] 334469 0
Co-intervention use.

Participants will complete a custom-developed table to indicate the frequency of use (over the past 6 months) of a range of pain and arthritis medications and co-interventions.
Timepoint [8] 334469 0
Baseline, and 6 months after randomization
Secondary outcome [9] 334470 0
Adverse events.

Adverse events will be defined as any problem experienced in the study knee or elsewhere in the body as a result of wearing the allocated study shoes. These will be self-reported by participants using a custom-developed table.
Timepoint [9] 334470 0
6 months after randomization
Secondary outcome [10] 334471 0
Self-rated compliance with study shoes over 6 months.

Rated by participants using an 11-point NRS for overall compliance over the 6 months where 0=shoes not worn at all and 10=shoes worn completely as instructed.
Timepoint [10] 334471 0
6 months after randomization
Secondary outcome [11] 334472 0
Mean hours wearing the study shoes per day.

Shoe wear will be recorded in a log book once per month for a one week period.
Timepoint [11] 334472 0
1, 2, 3, 4, 5 and 6 months after randomization
Secondary outcome [12] 334473 0
Number of participants who stopped wearing the study shoes.

Participants will indicate whether they stopped wearing either pair of their study shoes during the 6 months on a categorical scale (Yes or No).
Timepoint [12] 334473 0
6 months after randomization
Secondary outcome [13] 335784 0
Pain severity for the contralateral knee.

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [13] 335784 0
Baseline, and 6 months after randomization
Secondary outcome [14] 335785 0
Pain severity for the ipsilateral hip

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [14] 335785 0
Baseline, and 6 months after randomization
Secondary outcome [15] 335787 0
Pain severity for the contralateral hip.

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [15] 335787 0
Baseline, and 6 months after randomization
Secondary outcome [16] 335788 0
Pain severity for the ipsilateral foot/ankle.

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [16] 335788 0
Baseline, and 6 months after randomization
Secondary outcome [17] 335789 0
Pain severity for the contralateral foot/ankle.

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [17] 335789 0
Baseline, and 6 months after randomization
Secondary outcome [18] 335790 0
Pain severity for the back.

Scored on an 11-point NRS for average overall pain in the last week. Ranges from 0 to 10; where 0=no pain and 10=worst pain possible.
Timepoint [18] 335790 0
Baseline, and 6 months after randomization
Secondary outcome [19] 335791 0
Global improvement in pain.

Scored using a 7-point global rating of change Likert scale from with response options ranging from “much worse” to “much better” when compared to baseline. Participants indicating they are “moderately better” or “much better” will be classified as improved. All other respondents will be classified as not improved.
Timepoint [19] 335791 0
6 months after randomization
Secondary outcome [20] 335792 0
Global improvement in physical function.

Scored using a 7-point global rating of change Likert scale from with response options ranging from “much worse” to “much better” when compared to baseline. Participants indicating they are “moderately better” or “much better” will be classified as improved. All other respondents will be classified as not improved.
Timepoint [20] 335792 0
6 months after randomization

Eligibility
Key inclusion criteria
i) aged greater than or equal to 50 years;
ii) report knee pain on most days of the past month;
iii) report a minimum pain score of 4 on an 11-point numeric rating scale during walking over the previous week;
iv) demonstrate tibiofemoral osteophytes on x-ray; and
v) demonstrate moderate-severe (Grade 3-4) tibiofemoral OA on x-ray as determined by the Kellgren & Lawrence grading system
Minimum age
50 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
i) Lateral joint space narrowing greater than or equal to medial joint space narrowing on x-ray;
ii) suffered knee pain for <3 months;
iii) recent knee surgery (past 6 months) or planned surgery in next 6 months;
iv) current use of shoe orthoses, customized shoes or ankle braces;
v) current primary use of high heels, thongs or work boots that would restrict ability to wear study shoes 6 hours/day;
vi) had a hip or knee replacement on either side;
vii) had a high tibial osteotomy on either leg;
viii) had any knee injections in the past 3 months or planned injections in next 6 months;
ix) self-report any other muscular, joint or neurological condition affecting lower limb function;
x) self-report any systemic or inflammatory joint disease (eg rheumatoid arthritis);
xi) current or planned use of a gait aid in the next 6 months
xii) inability to understand written/spoken English
xiii) unable to fulfill study requirements (eg wearing shoes, attending appointments, completing outcomes, do not have foot size in the range of 8 to 13US for men, and 7 to 12US for women).

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Participants will be randomly allocated to either 1) Flat Flexible shoes; or 2) Stable Supportive shoes. Prior to randomization, participants will not be told about the types of footwear being investigated in the study, nor the hypotheses under investigation to reduce bias. Once allocated to a group, participants will also not be told the distinguishing features of their shoes in comparison to the other group.

A researcher not involved in recruitment, enrollment or collection of primary/secondary outcome measures, will allocate participants to a group, using a computer program.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation schedule will be prepared by the biostatistician stratified by Kellgren & Lawrence (KL) x-ray grade (3 or 4). The schedule will be stored on a password-protected website (REDCap) maintained by a researcher not involved in either participant recruitment or administration of primary/secondary outcome measures.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Efficacy
Statistical methods / analysis
We aim to detect the minimal clinically important difference (MCID) on primary outcomes between groups (1.8 (out of 10) for NRS pain and 6 (out of 68) for WOMAC function). We assume between-subject SDs of 2.7 and 11.4, and baseline to 6-month correlations of 0.21 and 0.39 for pain and function respectively (data from our footwear trial in similar sample). Using ANCOVA adjusted for baseline score, we need 46 per arm to achieve 90% power to detect MCID in pain and 65 per arm for function. Allowing for 20% attrition, we will recruit 82 people per arm (n=164).

A biostatistician will analyse blinded data. Main comparative analyses between groups will be performed using intention-to-treat. Multiple imputation will be used to account for missing data. For the primary hypothesis, differences in mean change in pain and function (baseline minus follow-up) will be compared between groups using linear regression modelling adjusted for baseline values and the stratifying variable of KL grade. Similar analyses will be conducted for continuous secondary outcomes. Improvement based on global change will be compared across groups using risk differences, calculated from fitted logistic regression models. A sensitivity analysis will estimate treatment effects assuming full adherence, using a two-stage least squares approach. Effects of patient characteristics on outcomes will be explored by including relevant terms in models. Standard diagnostic plots will be used to check model assumptions.

To assess whether the effect of shoe type on the primary outcomes is moderated by any of KL grade, Foot posture index (FPI) score, body mass or baseline score on the KOOS patellofemoral pain and OA subscale, appropriate interaction terms between randomised group and each of these variables will be included in regression models for the primary outcomes, for each potential effect modifier separately.

Recruitment
Recruitment status
Recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 15897 0
3010 - University Of Melbourne

Funding & Sponsors
Funding source category [1] 296354 0
Government body
Name [1] 296354 0
National Health and Medical Research Council
Address [1] 296354 0
GPO Box 1421
Canberra ACT 2601
Country [1] 296354 0
Australia
Primary sponsor type
University
Name
University of Melbourne
Address
Centre for Health Exercise and Sports Medicine
Department of Physiotherapy
School of Health Sciences
Level 7, Alan Gilbert Building
University of Melbourne VIC 3010
Country
Australia
Secondary sponsor category [1] 295286 0
None
Name [1] 295286 0
Address [1] 295286 0
Country [1] 295286 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 297584 0
University of Melbourne Human Research Ethics Committee
Ethics committee address [1] 297584 0
Research Ethics & Integrity
The University of Melbourne
Level 1, 21 Bedford St,
North Melbourne VIC 3051
Ethics committee country [1] 297584 0
Australia
Date submitted for ethics approval [1] 297584 0
23/03/2017
Approval date [1] 297584 0
23/05/2017
Ethics approval number [1] 297584 0
1748784

Summary
Brief summary
Knee osteoarthritis is a major problem in Australia and there is no cure for the disease. Non-drug strategies that help people to self-manage the condition are needed. Different types of shoes influence forces acting across the knee joint. We know that increased knee forces can contribute to the knee pain associated with knee osteoarthritis, and that high forces can increase the risk of the disease worsening over time. It is recommended that clinicians provide advice on “appropriate” footwear for people with knee osteoarthritis. However, there is little evidence from clinical trials to determine which shoes are best for self-managing knee osteoarthritis.

We are conducting a research study to compare two classes of readily available off-the-shelf shoes on knee osteoarthritis symptoms. To do this, we will allocate people via a random process into two different groups. Participants in each group will be provided with 2 pairs of different shoes to wear daily for 6 months. To ensure that this is a fair and unbiased evaluation, we will not disclose the differences in the shoe classes between the two groups until the end of the study. There will be an equal number of participants in each group, and participants will not be able to choose which group they are in.

The findings of this study will help determine which shoes are best for people with knee osteoarthritis and will guide clinicians in providing appropriate evidence-based footwear advice for their patients. The findings of this study will be published in medical journals and be presented at conferences.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 74518 0
Prof Rana Hinman
Address 74518 0
Centre for Health Exercise and Sports Medicine
Department of Physiotherapy
School of Health Sciences
Level 7, Alan Gilbert Building
University of Melbourne VIC 3010
Country 74518 0
Australia
Phone 74518 0
+61383443223
Fax 74518 0
Email 74518 0
ranash@unimelb.edu.au
Contact person for public queries
Name 74519 0
Mr Ben Metcalf
Address 74519 0
Centre for Health Exercise and Sports Medicine
Department of Physiotherapy
School of Health Sciences
Level 7, Alan Gilbert Building
University of Melbourne VIC 3010
Country 74519 0
Australia
Phone 74519 0
+61383448127
Fax 74519 0
Email 74519 0
b.metcalf@unimelb.edu.au
Contact person for scientific queries
Name 74520 0
Prof Rana Hinman
Address 74520 0
Centre for Health Exercise and Sports Medicine
Department of Physiotherapy
School of Health Sciences
Level 7, Alan Gilbert Building
University of Melbourne VIC 3010
Country 74520 0
Australia
Phone 74520 0
+61383443223
Fax 74520 0
Email 74520 0
ranash@unimelb.edu.au

No data has been provided for results reporting
Summary results
Not applicable