Flexible FlatfootNCT06567509
Effectiveness of Core Stability Exercises on Foot Posture, Function and Limb Alignment in Flexible Flat Feet Patients
A study testing Core stability exercises and Short foot exercises and Conventional foot exercises and short foot exercises in people with Flexible Flatfoot, run by International Islamic University Malaysia at 1 site in Malaysia.
Trial summary
Flexible flat foot is a very common musculoskeletal disorder of lower limbs in general population. Studies have reported that a flexible flat foot causes an alteration in the human body structures and lower limb kinetics due to a rotational torque in the tibia and femur which in turn affects the lumbar spine. Read more about this study
- Who is it for?
- Ages 18 to 30 years
- Conditions the study is for
- Flexible Flatfoot
- What is being tested?
- Core stability exercises and Short foot exercises and Conventional foot exercises and short foot exercises
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 85 participants
- Where
- 1 siteMalaysia
- Study dates
- 16 Oct 2024to 16 Jan 2026
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 30 years
- All sexes
- No healthy volunteers
- Adult
Who may be able to join
- Subjects of age group 18 to 30 years.
- Both males and females.
- No recent history of lower limb injuries.
- Subjects with bilateral flexible flat feet as per the definition.
- Subjects with positive navicular drop test (> 10mm).
- Subjects with Positive Jack toe rising test.
Who cannot join
- Rigid flat foot
- Subject who are involved in a specific sport at least 2 h /day and 3 times a week regularly.
- History of arthritic symptoms of lower limb joints.
- History of any ligament or tendon injuries around ankle, knee, or hip joint.
- History of any limb surgery or back surgery.
- Chronic back pain.
- Any history of neurological deficit or diabetic neuropathy.
Trial locations and contacts
1 site in 1 country.
Malaysia1 site
Department of Physical Rehabilitation Sciences / Kulliyah of Allied Health Sciences / International Islamic university of Malaysia
Kuantan, Pahang, 25200
About this study
Official title: Identification of Exercise Components of Core Stability and Their Effectiveness on Foot Posture, Foot Function, and Lower Limb Alignment in Adults With Flexible Flat Feet
Flexible flat foot is a very common musculoskeletal disorder of lower limbs in general population. Studies have reported that a flexible flat foot causes an alteration in the human body structures and lower limb kinetics due to a rotational torque in the tibia and femur which in turn affects the lumbar spine. This altered mechanics affects the musculature around the lumbar spine especially the core muscles. A strong link between core muscles and lower limb control, foot posture and pressure force has been found in previous studies. While the role of core muscles on lower limb posture and functions has been determined, there is lack of evidence on the benefits of core stabilization exercises on foot arch deficits. Hence, the proposed study will determine the exercise components of core muscles training that are relevant for the flat foot pathology and then will experiment its effects on the foot posture and function. The first step of the proposed study will begin with an extensive literature survey to identify the components of core stability training that have been recommended in the management of lower limbs dysfunction. Then, a protocol of core muscles training will be devised and followed up with a pilot study where the purpose will be to assess the feasibility of the training protocol. The final step of the proposed study will be an experimental study. The subjects for the experimental study will be selected based on predetermined inclusion and exclusion criteria and will be allocated alternately into experimental and control group. The experimental group will receive core stability training as an intervention. Whereas the control group will receive traditional conventional physiotherapy treatment. The foot posture, foot function and lower limb alignment will be assessed before and after the completion of treatment protocol. The data will be analyzed for any differences between group differences and between group differences. The outcomes of the proposed study may have an implication in the lower limb alignment and foot arch correction strategies.
Read the detailed description
Objective of study:
To assess effect of core stability on foot posture, function and limb alignment in adults with flexible flat feet.
Description of Methodology
The study will be conducted in the International Islamic University Malaysia (IIUM) Kuantan Campus at the research lab of the Department of Physical Rehabilitation Sciences. The pilot randomized control trial will be done to test the protocol of exercises, which were developed by authors after a systematic review. Then a randomized control trial will be conducted in the next phase.
A total of 20 Subjects(Pilot trial) with flexible flat feet will be chosen from the Kuantan community between the age group of 18 to 35 years using simple random sampling for pilot RCT and sample size for the Main RCT will be calculated after the completion of Pilot RCT.
Detailed Description of patient selection :
Subjects with flat feet will be identified from Kuantan community by one researcher using advertisement banners and inviting the general population to participate in the research and the patients will be identified using predetermined inclusion and exclusion criteria.
After that the subjects will be randomly allocated to two groups (Experimental group and control group) using random generator by one investigator, who will not be a part of assessment and administering exercises to the patients and allocation will be concealed. Then base line assessment of the patients for: Staheli Plantar arch Index, Rare foot angle, Foot function Index, Qangle, and core muscle endurance will be assessed for both the groups by an assessor who will have no role in administering exercises to the patients. Then two clinicial physiotherapists will be assigned for administering the exercises to the experimental group and control group. The clinician who will be treating the experimental group will only treat patients of the experimental group and the physiotherapist assigned to control group will be only treating patients in control group.
Details of Protocol of exercises for Pilot study:
A detailed literature survey was conducted and a systematic review was done by five researchers to identify the components of core stability exercises that may have a potential to improve lower limb function and also identify the parameters of exercise prescription. Review was conducted from December 2023 untill August 2024 and was registered with PROSPERO with registration number (CRD42023491502). Now after all the components and parameters have been identified exercises will be implemented with following details:
Pilot Experimental group:
Experimental group will undergo following components of core stability exercises : 1. Cross curl ups 2. Bridges 3. Side bridges 4. Planks 5. Quadrepedal stance
The exercises will be implemented for a period of 6 weeks in three phases:
- Phase 1 will last for week 1-2.
- Phase 2 will last from week 3-4.
- Phase 3 will last from week 5-6.
In phase 1 the exercises will be performed with 15 seconds hold for isometric contraction and 10 repetitions for isotonic component, 3 times and 120 seconds rest between the sets.
In Phase 2 same exercises will be performed with 20 seconds hold or 15 repetitions (isometric or isotonic respectively), 3 time and 120 seconds rest between the sets.
In Phase 3 same exercises will be performed with 25 seconds hold or 20 repetitions (isometric or isotonic respectively), 3 time and 120 seconds rest between the sets.
The patients will be taught the exercises in a face to face session at the start of the session and then will follow the exercises three times weekly as home exercises, i.e.... In phase 1 on Monday the patients will visit the research Lab and the assigned physiotherapist will administer the core stability exercise session and provide education about the exercise programme and then the patients will perform these exercises three time weekly for next 2 weeks. After the completion of phase 1 the patients will again visit the research Lab and assigned physiotherapist will again administer the core stability exercise session and provide education and the patients will follow the exercises three times weekly. Same procedure will be followed for the phase 3 also. For home exercises session a soft copy of pdf booklet will be circulated to the patients via a common WhatsApp group and reminders for the exercises will be given via WhatsApp group. Also a spread sheet using google forms will be created and shared with all the patients to report the attendance and to address any difficulties the subjects are facing while performing exercises in order to get the feed back about protocol.
The exercises will be preceded with a 5 minutes warm up exercises( Cat camel exercises \& supine roiling) 3 times each AND end with a cool down exercise of self-stretching of hamstrings and calf in long sitting position 3 times with 10 seconds hold.
Pilot Control group:
A physiotherapist assigned for the control group will administer first session of every phase in face to face mode and the remaining sessions of the phase will be home programmed with a soft copy booklet of exercises provided to each participant via a separate WhatsApp group in a similar fashion as that of experimental group.
Pilot control group will undergo foot exercises three time weekly for a period of 6 weeks with following exercises:
Exercise session will start with arm up session of 5 minutes with Active range of motion exercises (Knee and hip flexion) 10 repetitions × 2 sets
Then a Training session for foot muscles will follow with following exercises:
Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
Finally end with Cool down of calf stretches in long sitting for 10 seconds hold × 3 sets
After the completion of six weeks of exercises, Staheli Plantar arch Index, Rare foot angle, Foot function Index, Q angle, and core muscle endurance will be again measured by the same assessor who had assessed these outcomes earlier at the baseline.
.
Details of Protocol of exercises for Main RCT:
(Sample size for Main RCT will be calculated after the completion of Pilot RCT.)
After the completion of pilot study the feed back from the participants, which was gathered verbally using interview method at the end of every 2 weeks and will be analyzed and any fine tuning of the protocol, if required will be done and the exercises will be administered in the same fashion as mentioned in the pilot trial i.e... in nutshell two groups will be created (Experimental and control ) using random generator by one investigator and then the subjects will be assessed for the outcomes already mentioned (Staheli Plantar arch Index, Rare foot angle, Q angle, and core muscle endurance) in both the groups by an assessor who will have no role in administering exercises to the patients. Then the core stability exercises and conventional foot exercises will be administered to experimental and control groups respectively by two separate physiotherapists in similar way as described in the pilot study with same parameters in three phases for 6 weeks with treatment administered three times weekly. Finally arch index, rare foot angle, foot function Index, Q angle and core muscle endurance will be again measures in both the groups.
The Pilot study was completed on 30th January 2024 while the recruitment had started on 16th October 2024 and the main trial will resume later:
Completed Pilot study Description:
The study aimed to evaluate the preliminary effects and feasibility with acceptability of an exercise program developed based on a systematic review. As part of this, a pilot randomized controlled trial (RCT) was conducted and has now been completed. The feasibility assessment included recruitment rate, adherence, participant feedback, and preliminary outcome measures. Data analysis for the pilot phase has been completed. Statistical analysis(using percentage for ordinal data, means and standard deviation for continuous data to describe the sample) was also conducted on the collected data to assess the feasibility and preliminary effects of the intervention.
The data from the pilot study was used to calculate the required sample size for main RCT. Which has been calculated as 62 participants including 20% buffer to cover up attrition if any.
The study will resume at a later stage to proceed with the main trial as per the original protocol. No changes have been made to the study design or methodology following the pilot phase. The primary completion date and final study completion date remain unchanged, as they reflect the timeline for the full trial.
Resumption for Main RCT:
Main RCT has started screening the subjects from general population from 10th July 2025
- Conditions
- Flexible Flatfoot
- Being tested
- Core stability exercises and Short foot exercises, Conventional foot exercises and short foot exercises
- Keywords
- Flexible Flatfoot, Core stability, Muscle endurance
- Medical subject headings
- Flatfoot
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Core stability exercises and Short foot exercisesOther
Core stabilty exercises are the exercises where subjects will be trained to perform exercises like: Curl ups, bridging, side bridges, Planks, and Quadripedal stance exercises in a phased manner, each phase lasting 2 weeks. Complexities and duration of exercises will be increased in each phase. Short foot exercises for control group will include traditional treatment of stretching and strengthening of foot musculature.
Conventional foot exercises and short foot exercisesOther
Ankle dorsiflexion, Plantar flexion, Inversion and Eversion range of motion exercises
| Study group | Role | What they receive |
|---|---|---|
| Pilot experimental group | Experimental | Phase 1: 1. Cross Curl 10 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 15 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 15 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 15 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance. 15 sec hold × 3 times 120 sec rest between the sets
Phase 2: 1. Cross Curl ups 15 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 20 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 20 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 20 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance 20 sec hold × 3 times 120 sec rest between the sets Phase 3: 1. Cross Curl ups 25 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift / side bridge/Planks/Quadreped 25 sec hold × 3 times 120 sec rest between the sets. Receives: Other: Core stability exercises and Short foot exercises |
| Pilot Control group | Other | Conventional foot exercises for control group (3 times weekly for 6 weeks)
A. Warm up:
Active ROM exercise (Knee and hip flexion) 10 repetitions × 2 sets)
B. Training:
* Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
C. Cool down:
• Calf stretches in long sitting for 10 sec hold × 3 sets. Receives: Other: Conventional foot exercises and short foot exercises |
| Main RCT Experimental group | Experimental | Phase 1: 1. Cross Curl 10 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 15 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 15 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 15 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance. 20 sec hold × 3 times 120 sec rest between the sets
Phase 2: 1. Cross Curl ups 15 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 20 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 20 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 20 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance 20 sec hold × 3 times 120 sec rest between the sets
Phase 3 : 1. Cross Curl ups 20 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift / side bridges/ planks/Quadrepedal stance 20 sec hold each × 3 times 120 sec rest between the sets Receives: Other: Core stability exercises and Short foot exercises |
| Main RCT Control Group | Other | Conventional foot exercises for control group (3 times weekly for 6 weeks)
A. Warm up:
Active ROM exercise (Knee and hip flexion) 10 repetitions × 2 sets)
B. Training:
* Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
* Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
C. Cool down:
• Calf stretches in long sitting for 10 sec hold × 3 sets. Receives: Other: Conventional foot exercises and short foot exercises |
What is being measured
The primary outcome is the main question the study is designed to answer.
Staheli Plantar Arch Index (SPAI)
A 5 mm rubber pad was inked and used to ink the participant's foot. Participants sat first, then placed the testing foot on the inked pad and stood in tandem stance with the non-testing foot outside. A half-squat with slight hip and knee flexion ensured full foot contact. The inked foot was then placed on A4 paper while repeating the half-squat to transfer a clear footprint. A line of tangency from most medial foot edge and the heel was drawn using a ruler. Perpendicular line was drawn from midpoint of this line, crossing foot. Same procedure was repeated for heel tangency point. This process provided the measurements of the support width of the midfoot region (A) and the heel region (B) in millimeters. The Plantar Arch Index (PI) was then calculated using the formula (Plantar Arch Index (PI)=A/B) in millimeters.
0.8 mm = flexible flatfoot
↓ Arch Index = improvement (Putu Janiartha et al., 2023)
Values represent mean change scores (post-pre), comparisons performed using MANCOVA
Measured: Measured at baseline and after 6 weeks of Intervention
Foot Posture (Rare Foot Angle)
The rear foot angle (RFA) will be used to assess the calcaneal valgus. Four points will be marker in the lower limb with the subject is in standing position with talus in neutral position:
Base of calcaneus as mark 1, Subtalar joint (Centre of Achillies tendon attachment) as mark 2 and centre of posterior aspect of calf 15 cm above the 2nd mark as mark 3. A straight line will be drawn using a marker from point 2 to point 1. Then a line will be drawn from point 3 to point 2. The angle formed between the two lines with point 2 as fulcrum is the rare foot angle and will be measure using a universal goniometer.
The values represent mean change scores (post-pre). Group comparisons were performed using MANCOVA.
Measured: Will be assessed at baseline and after 6 weeks in both the groups.
Lower Limb Alignment (Left Q Angle)
The 'Q angle' will be measured by extending a line from anterior superior iliac spine of the pelvic bone to the center point of patella and extending another line from tibial tubercle of tibia to the center point of patella. The junction between these two lines is the 'Q angle' and will be measured using a universal goniometer.
Values represent mean change scores (post-pre).
Measured: Will be assessed at baseline and after 6 weeks in both the groups.
Foot Function Index (FFI)
The Foot Function Index (FFI) was initially included as an outcome measure in the study protocol. However, during the implementation phase, it was found to have feasibility limitations and reduced sensitivity in detecting changes within the study population. Therefore, the FFI was not collected for the main trial, and no data are reported for this outcome.
Measured: Planned to assess at baseline and after 6 weeks of intervention
Secondary outcomes (3)
Core Muscle Endurance (MacGill Protocol): Isometric Extensor Test
Isometric extensor test:
The subject will lay down prone on the bed with his or her lower body from ankles to hips fixed to the testing bed. A chair of the height of the testing bed will be placed in front of the bed so that patient's upper body can be rested on. Then slowly the chair will be removed, and the patient will be asked to maintain the extension of trunk with two hands crossed over on the opposite shoulders. Time in seconds will be recorder using a stopwatch from the time the subject assumed the horizontal position till the patient deviates from the horizontal position or patient verbally quits the test.
This outcome was collected as exploratory measure but was not included in the final analysis.
Measured: Will be assessed at baseline and after 6 weeks in both the groups.
Core Muscle Endurance (MacGill Protocol): Isometric Flexor Test
Isometric flexor test:
The flexor endurance will be tested by asking the subject to lay in a sit-up posture with hips and knees flexed 90 degrees and the back resting against a wedge inclined at 60 degrees and hands of subject are on the opposite shoulders with toes strapped. The posterior wedge is pulled backwards 10 cm and the subject is allowed to maintain the flexed posture as long as possible and the time from the removal of wedge till any postural deviation is noted using a stop watch. Deviation is noted if the back touches the wedge.
This outcome was collected as an exploratory measure but was not included in the final predefined outcome analysis.
Measured: Will be assessed at baseline and after 6 weeks in both the groups.
Core Muscle Endurance (MacGill Protocol): Isometric Flexor Test (Side Bridges Test, Left & Right)
Side bridges test (Left and right):
The subject is instructed to lie inside bridge position and place one elbow 90 degrees flexed below the shoulder, and the legs are extended in line with the trunk with one foot positioned in front of the another. the second hand is crossed and kept on the opposite shoulder. The test will then be started with the patient lifting his or her pelvis from the ground and maintaining this position and the failure will be if the back no longer remains straight or if the pelvis drops to the floor. The time will be noted using a stopwatch. The test is performed for both right side and left side.
This outcome was collected as an exploratory measure but was not included in the final predefined outcome analysis.
Measured: Will be assessed at baseline and after 6 weeks in both the groups.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Aug 2024
- Study start16 Oct 2024
- Primary completion15 Jan 2026
- Study completion16 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for Flexible FlatfootStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- This study will have two phases First phase(Pilot RCT study) Second phase (Randomized control trial). But The pilot study was only to report feasibility and acceptability of intervention programme.
- Masking
- Double blind
- Who is masked
- Investigator, Outcomes assessor
- Enrolment
- 85 participants (actual)
Sponsor and investigators
- Lead sponsor
- International Islamic University Malaysia
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Shahid Mohd Dar, International Islamic University Malaysia
- Investigators
- Shahid M Dar, MPT, Principal investigator, International Islamic University of Malaysia
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06567509
- Sponsor's protocol ID
- IREC 2024-257
- Status last verified
- Mar 2026
- First submitted
- 19 Aug 2024
- Last updated
- 14 Apr 2026
- Results posted
- Yes, on ClinicalTrials.gov
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Juniartha, I. P., Tinduh, D., Nugraheni, N., Pawana, I. P. A., Setiawati, R., & Melaniani, S. (2023). The validity and reliability of various footprint analysis in flatfoot diagnosis of competitive athletes. Bali Medical Journal, 12(1), 851-856. https://doi.org/10.15562/bmj.v12i1.4071
Aenumulapalli A, Kulkarni MM, Gandotra AR. Prevalence of Flexible Flat Foot in Adults: A Cross-sectional Study. J Clin Diagn Res. 2017 Jun;11(6):AC17-AC20. doi: 10.7860/JCDR/2017/26566.10059. Epub 2017 Jun 1.
PubMed 28764143Anvita Telang, & Supriya Dhumale. (2020). Comparison of Core Stability in Individuals with Flexible Flat Foot and Normal Foot. International Journal of Science and Research. 9 (5), 1232-1243.
Brijwasi T, Borkar P. A comprehensive exercise program improves foot alignment in people with flexible flat foot: a randomised trial. J Physiother. 2023 Jan;69(1):42-46. doi: 10.1016/j.jphys.2022.11.011. Epub 2022 Dec 14.
PubMed 36526555Eloho Nyerhovwo Igbinedion, Augustina Oghenevwaerhe Jewo, God'swill Okoro, & John Chinedu Obianke. (2022). Prevalence of Flat Foot using Plantar Arch Index among Young Adults of Delta State Nigeria. Mal J Med Health Sci,18(3), 112-117.
Khamis S, Yizhar Z. Effect of feet hyperpronation on pelvic alignment in a standing position. Gait Posture. 2007 Jan;25(1):127-34. doi: 10.1016/j.gaitpost.2006.02.005. Epub 2006 Apr 18.
PubMed 16621569Chevidikunnan MF, Al Saif A, Gaowgzeh RA, Mamdouh KA. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome. J Phys Ther Sci. 2016 May;28(5):1518-23. doi: 10.1589/jpts.28.1518. Epub 2016 May 31.
PubMed 27313363
Study at a glance
From the registry record, last updated by the sponsor on 14 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Identification of Exercise Components of Core Stability and Their Effectiveness on Foot Posture, Foot Function, and Lower Limb Alignment in Adults With Flexible Flat Feet
- ClinicalTrials.gov ID
- NCT06567509
- Acronym / sponsor ID
- IREC 2024-257
- Conditions
- Flexible Flatfoot
- Keywords
- Flexible Flatfoot, Core stability, Muscle endurance
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 85 participants (actual)
- Lead sponsor
- International Islamic University MalaysiaUniversity, hospital or other
- Study start
- 16 Oct 2024 (actual)
- Primary completion
- 15 Jan 2026 (actual)
- Study completion
- 16 Jan 2026 (actual)
- First posted
- 22 Aug 2024 (actual)
- Results
- Posted 14 Apr 2026
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Flexible flat foot is a very common musculoskeletal disorder of lower limbs in general population. Studies have reported that a flexible flat foot causes an alteration in the human body structures and lower limb kinetics due to a rotational torque in the tibia and femur which in turn affects the lumbar spine. This altered mechanics affects the musculature around the lumbar spine especially the core muscles. A strong link between core muscles and lower limb control, foot posture and pressure force has been found in previous studies. While the role of core muscles on lower limb posture and functions has been determined, there is lack of evidence on the benefits of core stabilization exercises on foot arch deficits. Hence, the proposed study will determine the exercise components of core muscles training that are relevant for the flat foot pathology and then will experiment its effects on the foot posture and function. The first step of the proposed study will begin with an extensive literature survey to identify the components of core stability training that have been recommended in the management of lower limbs dysfunction. Then, a protocol of core muscles training will be devised and followed up with a pilot study where the purpose will be to assess the feasibility of the training protocol. The final step of the proposed study will be an experimental study. The subjects for the experimental study will be selected based on predetermined inclusion and exclusion criteria and will be allocated alternately into experimental and control group. The experimental group will receive core stability training as an intervention. Whereas the control group will receive traditional conventional physiotherapy treatment. The foot posture, foot function and lower limb alignment will be assessed before and after the completion of treatment protocol. The data will be analyzed for any differences between group differences and between group differences. The outcomes of the proposed study may have an implication in the lower limb alignment and foot arch correction strategies.
Detailed description
Objective of study:
To assess effect of core stability on foot posture, function and limb alignment in adults with flexible flat feet.
Description of Methodology
The study will be conducted in the International Islamic University Malaysia (IIUM) Kuantan Campus at the research lab of the Department of Physical Rehabilitation Sciences. The pilot randomized control trial will be done to test the protocol of exercises, which were developed by authors after a systematic review. Then a randomized control trial will be conducted in the next phase.
A total of 20 Subjects(Pilot trial) with flexible flat feet will be chosen from the Kuantan community between the age group of 18 to 35 years using simple random sampling for pilot RCT and sample size for the Main RCT will be calculated after the completion of Pilot RCT.
Detailed Description of patient selection :
Subjects with flat feet will be identified from Kuantan community by one researcher using advertisement banners and inviting the general population to participate in the research and the patients will be identified using predetermined inclusion and exclusion criteria.
After that the subjects will be randomly allocated to two groups (Experimental group and control group) using random generator by one investigator, who will not be a part of assessment and administering exercises to the patients and allocation will be concealed. Then base line assessment of the patients for: Staheli Plantar arch Index, Rare foot angle, Foot function Index, Qangle, and core muscle endurance will be assessed for both the groups by an assessor who will have no role in administering exercises to the patients. Then two clinicial physiotherapists will be assigned for administering the exercises to the experimental group and control group. The clinician who will be treating the experimental group will only treat patients of the experimental group and the physiotherapist assigned to control group will be only treating patients in control group.
Details of Protocol of exercises for Pilot study:
A detailed literature survey was conducted and a systematic review was done by five researchers to identify the components of core stability exercises that may have a potential to improve lower limb function and also identify the parameters of exercise prescription. Review was conducted from December 2023 untill August 2024 and was registered with PROSPERO with registration number (CRD42023491502). Now after all the components and parameters have been identified exercises will be implemented with following details:
Pilot Experimental group:
Experimental group will undergo following components of core stability exercises : 1. Cross curl ups 2. Bridges 3. Side bridges 4. Planks 5. Quadrepedal stance
The exercises will be implemented for a period of 6 weeks in three phases:
- Phase 1 will last for week 1-2.
- Phase 2 will last from week 3-4.
- Phase 3 will last from week 5-6.
In phase 1 the exercises will be performed with 15 seconds hold for isometric contraction and 10 repetitions for isotonic component, 3 times and 120 seconds rest between the sets.
In Phase 2 same exercises will be performed with 20 seconds hold or 15 repetitions (isometric or isotonic respectively), 3 time and 120 seconds rest between the sets.
In Phase 3 same exercises will be performed with 25 seconds hold or 20 repetitions (isometric or isotonic respectively), 3 time and 120 seconds rest between the sets.
The patients will be taught the exercises in a face to face session at the start of the session and then will follow the exercises three times weekly as home exercises, i.e.... In phase 1 on Monday the patients will visit the research Lab and the assigned physiotherapist will administer the core stability exercise session and provide education about the exercise programme and then the patients will perform these exercises three time weekly for next 2 weeks. After the completion of phase 1 the patients will again visit the research Lab and assigned physiotherapist will again administer the core stability exercise session and provide education and the patients will follow the exercises three times weekly. Same procedure will be followed for the phase 3 also. For home exercises session a soft copy of pdf booklet will be circulated to the patients via a common WhatsApp group and reminders for the exercises will be given via WhatsApp group. Also a spread sheet using google forms will be created and shared with all the patients to report the attendance and to address any difficulties the subjects are facing while performing exercises in order to get the feed back about protocol.
The exercises will be preceded with a 5 minutes warm up exercises( Cat camel exercises \& supine roiling) 3 times each AND end with a cool down exercise of self-stretching of hamstrings and calf in long sitting position 3 times with 10 seconds hold.
Pilot Control group:
A physiotherapist assigned for the control group will administer first session of every phase in face to face mode and the remaining sessions of the phase will be home programmed with a soft copy booklet of exercises provided to each participant via a separate WhatsApp group in a similar fashion as that of experimental group.
Pilot control group will undergo foot exercises three time weekly for a period of 6 weeks with following exercises:
Exercise session will start with arm up session of 5 minutes with Active range of motion exercises (Knee and hip flexion) 10 repetitions × 2 sets
Then a Training session for foot muscles will follow with following exercises:
Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets)
Finally end with Cool down of calf stretches in long sitting for 10 seconds hold × 3 sets
After the completion of six weeks of exercises, Staheli Plantar arch Index, Rare foot angle, Foot function Index, Q angle, and core muscle endurance will be again measured by the same assessor who had assessed these outcomes earlier at the baseline.
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Details of Protocol of exercises for Main RCT:
(Sample size for Main RCT will be calculated after the completion of Pilot RCT.)
After the completion of pilot study the feed back from the participants, which was gathered verbally using interview method at the end of every 2 weeks and will be analyzed and any fine tuning of the protocol, if required will be done and the exercises will be administered in the same fashion as mentioned in the pilot trial i.e... in nutshell two groups will be created (Experimental and control ) using random generator by one investigator and then the subjects will be assessed for the outcomes already mentioned (Staheli Plantar arch Index, Rare foot angle, Q angle, and core muscle endurance) in both the groups by an assessor who will have no role in administering exercises to the patients. Then the core stability exercises and conventional foot exercises will be administered to experimental and control groups respectively by two separate physiotherapists in similar way as described in the pilot study with same parameters in three phases for 6 weeks with treatment administered three times weekly. Finally arch index, rare foot angle, foot function Index, Q angle and core muscle endurance will be again measures in both the groups.
The Pilot study was completed on 30th January 2024 while the recruitment had started on 16th October 2024 and the main trial will resume later:
Completed Pilot study Description:
The study aimed to evaluate the preliminary effects and feasibility with acceptability of an exercise program developed based on a systematic review. As part of this, a pilot randomized controlled trial (RCT) was conducted and has now been completed. The feasibility assessment included recruitment rate, adherence, participant feedback, and preliminary outcome measures. Data analysis for the pilot phase has been completed. Statistical analysis(using percentage for ordinal data, means and standard deviation for continuous data to describe the sample) was also conducted on the collected data to assess the feasibility and preliminary effects of the intervention.
The data from the pilot study was used to calculate the required sample size for main RCT. Which has been calculated as 62 participants including 20% buffer to cover up attrition if any.
The study will resume at a later stage to proceed with the main trial as per the original protocol. No changes have been made to the study design or methodology following the pilot phase. The primary completion date and final study completion date remain unchanged, as they reflect the timeline for the full trial.
Resumption for Main RCT:
Main RCT has started screening the subjects from general population from 10th July 2025
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (investigator, outcomes assessor)
- Number of arms
- 4
- Model description
- This study will have two phases First phase(Pilot RCT study) Second phase (Randomized control trial). But The pilot study was only to report feasibility and acceptability of intervention programme.
| Arm | Type | Receives |
|---|---|---|
| Pilot experimental group | Experimental | Other: Core stability exercises and Short foot exercisesPhase 1: 1. Cross Curl 10 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 15 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 15 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 15 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance. 15 sec hold × 3 times 120 sec rest between the sets Phase 2: 1. Cross Curl ups 15 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 20 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 20 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 20 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance 20 sec hold × 3 times 120 sec rest between the sets Phase 3: 1. Cross Curl ups 25 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift / side bridge/Planks/Quadreped 25 sec hold × 3 times 120 sec rest between the sets. |
| Pilot Control group | Other | Other: Conventional foot exercises and short foot exercisesConventional foot exercises for control group (3 times weekly for 6 weeks) A. Warm up: Active ROM exercise (Knee and hip flexion) 10 repetitions × 2 sets) B. Training: * Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) C. Cool down: • Calf stretches in long sitting for 10 sec hold × 3 sets. |
| Main RCT Experimental group | Experimental | Other: Core stability exercises and Short foot exercisesPhase 1: 1. Cross Curl 10 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 15 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 15 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 15 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance. 20 sec hold × 3 times 120 sec rest between the sets Phase 2: 1. Cross Curl ups 15 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift 20 sec hold × 3 times 120 sec rest between the sets Side bridges (left and right) 20 sec hold × 3 times 120 sec rest between the sets 3. Planks on feet 20 sec hold × 3 times 120 sec rest between the sets 4. Quadripedal stance 20 sec hold × 3 times 120 sec rest between the sets Phase 3 : 1. Cross Curl ups 20 rept × 3 times 120 sec rest between the sets 2. Bridges with leg lift / side bridges/ planks/Quadrepedal stance 20 sec hold each × 3 times 120 sec rest between the sets |
| Main RCT Control Group | Other | Other: Conventional foot exercises and short foot exercisesConventional foot exercises for control group (3 times weekly for 6 weeks) A. Warm up: Active ROM exercise (Knee and hip flexion) 10 repetitions × 2 sets) B. Training: * Active dorsiflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active plantarflexion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active inversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) * Active eversion exercises in long sitting (10 sec hold × 15 repetitions ×2 sets) C. Cool down: • Calf stretches in long sitting for 10 sec hold × 3 sets. |
Who may qualify
- Ages
- 18 to 30 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (6 listed)
- Subjects of age group 18 to 30 years.
- Both males and females.
- No recent history of lower limb injuries.
- Subjects with bilateral flexible flat feet as per the definition.
- Subjects with positive navicular drop test (> 10mm).
Key exclusion criteria (7 listed)
- Rigid flat foot
- Subject who are involved in a specific sport at least 2 h /day and 3 times a week regularly.
- History of arthritic symptoms of lower limb joints.
- History of any ligament or tendon injuries around ankle, knee, or hip joint.
- History of any limb surgery or back surgery.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Core stability exercises and Short foot exercisesCore stabilty exercises are the exercises where subjects will be trained to perform exercises like: Curl ups, bridging, side bridges, Planks, and Quadripedal stance exercises in a phased manner, each phase lasting 2 weeks. Complexities and duration of exercises will be increased in each phase. Short foot exercises for control group will include traditional treatment of stretching and strengthening of foot musculature. | Other | Main RCT Experimental group, Pilot experimental group |
| Conventional foot exercises and short foot exercisesAnkle dorsiflexion, Plantar flexion, Inversion and Eversion range of motion exercises | Other | Main RCT Control Group, Pilot Control group |
Primary outcome
Staheli Plantar Arch Index (SPAI)
Time frame: Measured at baseline and after 6 weeks of Intervention
A 5 mm rubber pad was inked and used to ink the participant's foot. Participants sat first, then placed the testing foot on the inked pad and stood in tandem stance with the non-testing foot outside. A half-squat with slight hip and knee flexion ensured full foot contact. The inked foot was then placed on A4 paper while repeating the half-squat to transfer a clear footprint. A line of tangency from most medial foot edge and the heel was drawn using a ruler. Perpendicular line was drawn from midpoint of this line, crossing foot. Same procedure was repeated for heel tangency point. This process provided the measurements of the support width of the midfoot region (A) and the heel region (B) in millimeters. The Plantar Arch Index (PI) was then calculated using the formula (Plantar Arch Index (PI)=A/B) in millimeters. 0.8 mm = flexible flatfoot ↓ Arch Index = improvement (Putu Janiartha et al., 2023) Values represent mean change scores (post-pre), comparisons performed using MANCOVA
Foot Posture (Rare Foot Angle)
Time frame: Will be assessed at baseline and after 6 weeks in both the groups.
The rear foot angle (RFA) will be used to assess the calcaneal valgus. Four points will be marker in the lower limb with the subject is in standing position with talus in neutral position: Base of calcaneus as mark 1, Subtalar joint (Centre of Achillies tendon attachment) as mark 2 and centre of posterior aspect of calf 15 cm above the 2nd mark as mark 3. A straight line will be drawn using a marker from point 2 to point 1. Then a line will be drawn from point 3 to point 2. The angle formed between the two lines with point 2 as fulcrum is the rare foot angle and will be measure using a universal goniometer. The values represent mean change scores (post-pre). Group comparisons were performed using MANCOVA.
Lower Limb Alignment (Left Q Angle)
Time frame: Will be assessed at baseline and after 6 weeks in both the groups.
The 'Q angle' will be measured by extending a line from anterior superior iliac spine of the pelvic bone to the center point of patella and extending another line from tibial tubercle of tibia to the center point of patella. The junction between these two lines is the 'Q angle' and will be measured using a universal goniometer. Values represent mean change scores (post-pre).
Foot Function Index (FFI)
Time frame: Planned to assess at baseline and after 6 weeks of intervention
The Foot Function Index (FFI) was initially included as an outcome measure in the study protocol. However, during the implementation phase, it was found to have feasibility limitations and reduced sensitivity in detecting changes within the study population. Therefore, the FFI was not collected for the main trial, and no data are reported for this outcome.
3 secondary outcomes
Core Muscle Endurance (MacGill Protocol): Isometric Extensor Test
Time frame: Will be assessed at baseline and after 6 weeks in both the groups.
Core Muscle Endurance (MacGill Protocol): Isometric Flexor Test
Time frame: Will be assessed at baseline and after 6 weeks in both the groups.
Core Muscle Endurance (MacGill Protocol): Isometric Flexor Test (Side Bridges Test, Left & Right)
Time frame: Will be assessed at baseline and after 6 weeks in both the groups.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Apr 2026.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- BackgroundJuniartha, I. P., Tinduh, D., Nugraheni, N., Pawana, I. P. A., Setiawati, R., & Melaniani, S. (2023). The validity and reliability of various footprint analysis in flatfoot diagnosis of competitive athletes. Bali Medical Journal, 12(1), 851-856. https://doi.org/10.15562/bmj.v12i1.4071
- Background: PubMed 28764143Aenumulapalli A, Kulkarni MM, Gandotra AR. Prevalence of Flexible Flat Foot in Adults: A Cross-sectional Study. J Clin Diagn Res. 2017 Jun;11(6):AC17-AC20. doi: 10.7860/JCDR/2017/26566.10059. Epub 2017 Jun 1.
- BackgroundAnvita Telang, & Supriya Dhumale. (2020). Comparison of Core Stability in Individuals with Flexible Flat Foot and Normal Foot. International Journal of Science and Research. 9 (5), 1232-1243.
- Background: PubMed 36526555Brijwasi T, Borkar P. A comprehensive exercise program improves foot alignment in people with flexible flat foot: a randomised trial. J Physiother. 2023 Jan;69(1):42-46. doi: 10.1016/j.jphys.2022.11.011. Epub 2022 Dec 14.
- BackgroundEloho Nyerhovwo Igbinedion, Augustina Oghenevwaerhe Jewo, God'swill Okoro, & John Chinedu Obianke. (2022). Prevalence of Flat Foot using Plantar Arch Index among Young Adults of Delta State Nigeria. Mal J Med Health Sci,18(3), 112-117.
- Background: PubMed 16621569Khamis S, Yizhar Z. Effect of feet hyperpronation on pelvic alignment in a standing position. Gait Posture. 2007 Jan;25(1):127-34. doi: 10.1016/j.gaitpost.2006.02.005. Epub 2006 Apr 18.
- Background: PubMed 27313363Chevidikunnan MF, Al Saif A, Gaowgzeh RA, Mamdouh KA. Effectiveness of core muscle strengthening for improving pain and dynamic balance among female patients with patellofemoral pain syndrome. J Phys Ther Sci. 2016 May;28(5):1518-23. doi: 10.1589/jpts.28.1518. Epub 2016 May 31.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Shahid M Dar, MPT principal investigator
International Islamic University of Malaysia
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Core stability exercises and Short foot exercises and Conventional foot exercises and short foot exercises in people with Flexible Flatfoot, run by International Islamic University Malaysia at 1 site in Malaysia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 14 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Malaysia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
Yes. Results are posted in the registry (first posted 14 Apr 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Staheli Plantar Arch Index (SPAI) (time frame: Measured at baseline and after 6 weeks of Intervention). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06567509, which also lists 7 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Apr 2026.