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Trial registered on ANZCTR


Registration number
ACTRN12618001864213
Ethics application status
Approved
Date submitted
13/11/2018
Date registered
15/11/2018
Date last updated
29/11/2018
Date data sharing statement initially provided
15/11/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
Footwear for Osteoarthritis of the Lateral Knee: the FOLK Trial.
Scientific title
Evaluating the effectiveness of Footwear on knee pain in people with Osteoarthritis of the Lateral Knee: the FOLK Trial.
Secondary ID [1] 296465 0
None
Universal Trial Number (UTN)
U1111-1222-9326
Trial acronym
FOLK
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Knee Osteoarthritis 310252 0
Condition category
Condition code
Musculoskeletal 308976 308976 0 0
Osteoarthritis

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This pragmatic comparative effectiveness trial will compare two different types of walking shoes manufactured by Asics.

Following baseline assessment, participants will be randomly allocated to receive either i) motion-control or; ii) neutral walking shoes. Participants will be provided a pair of shoes from their allocated group, to be worn daily for 6 months (minimum of 6 hours/day), after which participants will be reassessed remotely via paper or web-based questionnaires.

Motion-control shoes:
These shoes feature a dual density motion control mid-sole that is stiffer medially compared to laterally (Duomax).

Versus:

Neutral walking shoes:
These shoes have a mono-density mid-sole (i.e. equal medial and lateral stiffness).

Participants will 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). At the end of the intervention period, participants will rate their overall level of adherence using a numerical rating scale (0= shoes not worn at all to 10= shoes worn completely as instructed).
Intervention code [1] 312790 0
Treatment: Devices
Comparator / control treatment
The comparator shoe will be the neutral walking shoes.
These shoes have a mono-density mid-sole (i.e. equal medial and lateral stiffness).
Control group
Active

Outcomes
Primary outcome [1] 307944 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.
Timepoint [1] 307944 0
Baseline, and 6 months after randomization
Secondary outcome [1] 353409 0
Knee Injury and Osteoarthritis Outcome Score (KOOS) physical function subscale

Scored using 17 questions regarding knee function in the last week, with Likert response options ranging from None to Extreme.
Timepoint [1] 353409 0
Baseline, and 6 months after randomization
Secondary outcome [2] 353410 0
KOOS pain subscale

Scored using 9 questions about knee pain experienced in the last week, with Likert response options ranging from None to Extreme.
Timepoint [2] 353410 0
Baseline, and 6 months after randomization
Secondary outcome [3] 353411 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.
Timepoint [3] 353411 0
Baseline, and 6 months after randomization
Secondary outcome [4] 353412 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
Timepoint [4] 353412 0
Baseline, and 6 months after randomization
Secondary outcome [5] 353413 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. This is a composite secondary outcome.
Timepoint [5] 353413 0
Baseline, and 6 months after randomization
Secondary outcome [6] 353414 0
Health-related quality of life using the Assessment of Quality of Life instrument (AQoL-6D)

Scored using the 20-item Assessment of Quality of Life II Instrument (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.
Timepoint [6] 353414 0
Baseline, and 6 months after randomization
Secondary outcome [7] 353415 0
Physical Activity Scale for the Elderly (PASE)

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.
Timepoint [7] 353415 0
Baseline, and 6 months after randomization
Secondary outcome [8] 353416 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.
Timepoint [8] 353416 0
6 months after randomization
Secondary outcome [9] 353417 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.
Timepoint [9] 353417 0
6 months after randomization
Secondary outcome [10] 353418 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 (e.g. massage, ultrasound, etc).
Timepoint [10] 353418 0
Baseline, and 6 months after randomization
Secondary outcome [11] 353419 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 study shoes. These will be self-reported by participants using a custom-developed table. For example, increased knee pain, foot pain, knee swelling, etc.
Timepoint [11] 353419 0
6 months after randomization
Secondary outcome [12] 353420 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 [12] 353420 0
6 months after randomization
Secondary outcome [13] 353421 0
Mean hours of study shoe wear per day

Shoe wear will be recorded in a log book once per month for a one week period
Timepoint [13] 353421 0
1, 2, 3, 4, 5 and 6 months after randomization
Secondary outcome [14] 353423 0
Number of participants who stopped wearing the study shoes

Participants will indicate whether they stopped wearing the study shoes during the 6 months on a categorical scale (Yes or No).
Timepoint [14] 353423 0
6 months after randomization

Eligibility
Key inclusion criteria
i) aged 50 years or older;
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 Grade 2-4 tibiofemoral osteoarthritis on x-ray as determined by the Kellgren & Lawrence grading system; and
v) demonstrate grade of lateral tibiofemoral joint space narrowing greater than medial tibiofemoral joint space narrowing according to a radiographic atlas (where Grade 0=no narrowing, 1=mild narrowing, 2=moderate narrowing, 3=severe narrowing).

Minimum age
50 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
i) suffered knee pain for <3 months;
ii) recent knee surgery (past 6 months) or planned surgery in next 6 months;
iii) current use of shoe orthoses, customized shoes or ankle/knee braces;
iv) current primary use of high heels, thongs or work boots that would restrict ability to wear study shoes 6 hours/day;
v) had a hip or knee replacement on most painful knee;
vi) had a high tibial osteotomy on most painful knee;
vii) had any knee injections in the past 3 months or planned injections in next 6 months;
viii) self-report any other muscular, joint or neurological condition affecting lower limb function;
ix) self-report any systemic or inflammatory joint disease (e.g. rheumatoid arthritis);
x) current or planned use of a gait aid in the next 6 months
xi) inability to understand written/spoken English
xii) unable to commit to study requirements (e.g. wearing shoes, attending appointments, completing outcomes, do not have foot size in the range of 6 to 12US for women and 7 to 13US for men).

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 receive either i) motion-control or; ii) neutral walking shoes. To ensure participant blinding the plain language statement and consent processes will involve limited disclosure about the specific footwear features/shoe models under investigation and study hypotheses. Participants will be informed that the trial is evaluating two different undisclosed “types” of footwear to compare effects on knee osteoarthritis symptoms. Participants will not be told about the specific characteristics of the footwear under investigation, nor the specific shoe make/models that will be involved.

A researcher not involved in recruitment, enrolment 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 (permuted block sizes 6 to 12) stratified by KL grade (2, 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 minimum clinically important difference (MCID) on the primary outcome between groups (1.8 out of 10 units on NRS for walking pain). We conservatively assume a between-subject SD of 2.7 and a baseline to 6-month correlation of 0.21 based on previous similar trials (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 the MCID in pain. Allowing for 15% attrition, we will recruit 55 people per arm in total (n=110).

A bio-statistician 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 if required. For the primary hypothesis, differences in mean change in pain (baseline minus follow-up) will be compared between groups using linear regression models adjusted for baseline value of the primary outcome 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 to wear of the shoes (average of 6 hrs/day for 6 months, based on log book data), using an instrumental variables approach. Standard diagnostic plots will be used to check model assumptions.

To assess whether the effect of shoe group on the primary outcome of pain is moderated by any of KL grade, FPI score, knee alignment, 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 outcome, 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] 24499 0
3010 - University Of Melbourne

Funding & Sponsors
Funding source category [1] 301059 0
Government body
Name [1] 301059 0
National Health and Medical Research Council
Address [1] 301059 0
GPO Box 1421
Canberra ACT 2601
Country [1] 301059 0
Australia
Primary sponsor type
University
Name
The 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] 300666 0
None
Name [1] 300666 0
Address [1] 300666 0
Country [1] 300666 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 301813 0
University of Melbourne Human Research Ethics Committee
Ethics committee address [1] 301813 0
Research Ethics & Integrity
The University of Melbourne
Level 1, 21 Bedford St,
North Melbourne VIC 3051
Ethics committee country [1] 301813 0
Australia
Date submitted for ethics approval [1] 301813 0
10/09/2018
Approval date [1] 301813 0
06/11/2018
Ethics approval number [1] 301813 0

Summary
Brief summary
We are conducting a research study to compare the effects of daily use of motion-control and neutral walking shoes on lateral tibiofemoral osteoarthritis clinical outcomes, over 6 months. To do this we will randomly allocate participants to receive either i) motion-control or; ii) neutral walking shoes. Participants will be provided a pair of shoes from their allocated group, to be worn daily for 6 months (minimum of 6 hours/day).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 88198 0
Prof Rana Hinman
Address 88198 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 88198 0
Australia
Phone 88198 0
+61 383443223
Fax 88198 0
Email 88198 0
ranash@unimelb.edu.au
Contact person for public queries
Name 88199 0
Mrs Penny Campbell
Address 88199 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 88199 0
Australia
Phone 88199 0
+61 390355702
Fax 88199 0
Email 88199 0
penelope.campbell@unimelb.edu.au
Contact person for scientific queries
Name 88200 0
Prof Rana Hinman
Address 88200 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 88200 0
Australia
Phone 88200 0
+61 383443223
Fax 88200 0
Email 88200 0
ranash@unimelb.edu.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Data sharing may be negotiated on an individual basis.
What supporting documents are/will be available?
No other documents available
Summary results
Not applicable