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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Orthoses or Flip-Flops for Pain in the Heel: a randomised clinical trial
Scientific title
To evaluate the clinical efficacy of in-shoe orthotic devices and flip-flops in the management of heel pain
Secondary ID [1] 279819 0
Nil known
Universal Trial Number (UTN)
Trial acronym
OFFPH study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Heel pain 285705 0
Condition category
Condition code
Musculoskeletal 285888 285888 0 0
Other muscular and skeletal disorders
Physical Medicine / Rehabilitation 285889 285889 0 0

Study type
Description of intervention(s) / exposure
Contoured flip-flops: these are based on the foot-bed of a prefabricated in-shoe foot orthosis, which are to be worn daily during waking hours for the 12 week study period.
Intervention code [1] 284139 0
Treatment: Devices
Intervention code [2] 284670 0
Comparator / control treatment
Contoured in-shoe orthoses: these are much like the contoured flip-flops but will be worn inside shoes daily during waking hours for 12 weeks.

Flat flip-flops: these will be like typical non- contoured flip-flops made of rubber and worn daily during waking hours for the duration of the study (12weeks).
Control group

Primary outcome [1] 286398 0
15 point Global Rating of Change Scale: participants are asked to rate if they are better, same or worse, and if better or worse by how much on a 5 point scale (hence 15 points, 7 worse, 1 same and 7 better). This is a commonly used rating of change scale in clinical trials.
Timepoint [1] 286398 0
0, 4 and 12 weeks
Primary outcome [2] 286399 0
Lower Extremity Function Scale: Is a 20 item scale in which the participant rates the degree of difficulty (extreme to no difficulty over 0 to 4 points) on common weight bearing activities.
Timepoint [2] 286399 0
0, 4 and 12 weeks
Secondary outcome [1] 295776 0
Foot and Ankle Ability Measure: Is similar to the LEFS above (#2) but has 30 items, in two main parts, one dealing with higher order sports activities. It is used in order to cover the possibility of higher activity levels in our cohort. The clinicometric properties are otherwise similar to #2.
Timepoint [1] 295776 0
0, 4 and 12 weeks
Secondary outcome [2] 295777 0
Pain Numerical Rating Scale: An 11 point scale anchored by no pain at all at 0 and worst pain imaginable at 10 will be used to rate the worst and average level of pain severity the patient experienced in the past 24 hours and past week
Timepoint [2] 295777 0
0, 4 and 12 weeks
Secondary outcome [3] 295778 0
Patient Specific Function Scale: The participant choses a maximum of five tasks that they no longer can do unimpeded by their heel pain and scores the level of disability for each of these tasks on a 11 point numerical rating scale, where 0 is no interference to function and 10 is maximal interference with the task (i.e. no function, as in wheel chair bound or non-weight bearing on crutches)
Timepoint [3] 295778 0
0, 4 and 12 weeks
Secondary outcome [4] 295779 0
Foot Posture Index: This is a scale consisting of ratings of the therapist's observation of foot posture commonly used to score foot posture as pronated, neutral or supinated.
Timepoint [4] 295779 0
0, 4 and 12 weeks
Secondary outcome [5] 295780 0
Mid-foot height barefoot and in flip-flops will be measured non-invasively with digital calipers.
Timepoint [5] 295780 0
0, 4 and 12 weeks
Secondary outcome [6] 295781 0
Mid-foot width barefoot and in flip-flops: The mid foot measures are taken in weight bearing and non weight bearing with digital calipers, a non-invasive and non-painful procedure taking under 3 minutes (both feet weight bearing and non weight bearing)
Timepoint [6] 295781 0
0, 4 and 12 weeks

Key inclusion criteria
i. Report of (insidious non-traumatic onset) plantar heel pain for at least 1 month.
ii. First step pain in the morning of at least a 3/10 on a Pain Numerical Rating Scale.
iii. English communication skills to adequately understand questionnaires, allow valid treatment (orthoses) and outcome measurements to be performed
iv. Adequate shoes into which the active comparator can be fitted
v. Willingness to wear flip-flop or orthosis regularly for the 12 weeks duration of the trial
Minimum age
18 Years
Maximum age
70 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
i. History of previous therapy treatment of plantar fasciitis within the past month
ii. History or diagnosis of circulatory conditions
iii. Pregnancy
iv. Foot pathologies (including diabetes, gout, amputation, nerve impingement, tarsal tunnel syndrome, tumours, stress fracture, autoimmune disease, pitting oedema, lower extremity referred pain, previous plantar fascia surgical procedures, corticosteroid injections) within the past 12 months (for the transient conditions or treatments)
v. Participation in athletic activity 5 or more days per week for more than 90 minutes for day
vi. Other orthopaedic or neurological impairment that prevents a symmetrical walking pattern or an antalgic gait that was not attributed to plantar heel pain

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Concealed allocation by a computerised randomisation schedule developed by an off-site independent central trial unit (Queensland Clinical Trial Centre)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated radomisation schedule
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 284598 0
Government body
Name [1] 284598 0
National Health and Medical Research Council
Address [1] 284598 0
National Health and Medical Research Council
GPO Box 1421
Canberra ACT 2601
Country [1] 284598 0
Funding source category [2] 284608 0
Commercial sector/Industry
Name [2] 284608 0
Vasyli International USA
Address [2] 284608 0
4040 Civic Center Drive,
Suite 430,
San Rafael, CA, 94903
Country [2] 284608 0
United States of America
Primary sponsor type
Professor Bill Vicenzino
School of Health and Rehabiliation Sciences
Therapies Building 84A
Therapies Road
University of Queensland
St Lucia QLD 4072
Secondary sponsor category [1] 283515 0
Name [1] 283515 0
Professor Thomas McPoil
Address [1] 283515 0
Carroll Hall 414,
Regis University
3333 Regis Boulevard
Denver, Colorado 80221-1099
Country [1] 283515 0
United States of America
Secondary sponsor category [2] 285191 0
Name [2] 285191 0
Professor Paul Mintken
Address [2] 285191 0
School of Medicine Physical Therapy Programme
The Anschutz Medical Campus
13001 E 17th Place Aurora
University of Colorado
Denver CO USA 80045
Country [2] 285191 0
United States of America

Ethics approval
Ethics application status
Ethics committee name [1] 286696 0
Medical Research Ethics Committee
Ethics committee address [1] 286696 0
The University of Queensland
Cumbrae-Stewart Building
Research Road
Brisbane Qld 4072 Australia
Ethics committee country [1] 286696 0
Date submitted for ethics approval [1] 286696 0
Approval date [1] 286696 0
Ethics approval number [1] 286696 0

Brief summary
There are a number of studies that show that wearing an orthosis within a shoe helps resolution of heel pain. These orthoses often are prescribed to control excessive pronation, which is thought to be a mechanical factor contributing to overload and eventual pain of the tissues in the plantar heel region (also known as the planta fascia). Recently flip-flops have been designed with features similar to that of the orthoses, but without the need to be fitted within a shoe. A potential benefit of a flip-flop is that the high pain levels felt on first step in in the morning might be prevented if a flip-flop in the shape of an orthosis is worn. Wearing the flip-flop continually then might help relieve tissue stress of the plantar fascia and aid resolution of the problem. Interestingly, the material that flip-flops are made of might also be responsible for any pain relieving effect, hence the inclusion of a flat flip-flop as a comparator in this study. The aim of this study is to test if there are any differences between an in-shoe foot orthosis, a shaped flip-flop and a flat flip-flop over 12 weeks wear.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 33698 0
Address 33698 0
Country 33698 0
Phone 33698 0
Fax 33698 0
Email 33698 0
Contact person for public queries
Name 16945 0
Professor Bill Vicenzino
Address 16945 0
School of Health and Rehabiliation Sciences
Therapies Building 84A
Therapies Road
University of Queensland
St Lucia QLD 4072
Country 16945 0
Phone 16945 0
+617 3365 2781
Fax 16945 0
+617 33651622
Email 16945 0
Contact person for scientific queries
Name 7873 0
Professor Bill Vicenzino
Address 7873 0
School of Health and Rehabiliation Sciences
Therapies Building 84A
Therapies Road
University of Queensland
St Lucia QLD 4072
Country 7873 0
Phone 7873 0
+617 3365 2781
Fax 7873 0
+617 33651622
Email 7873 0

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