Effects of Custom 3D Printed Insoles and Short Foot Exercises in Pes Planus

The Effect of Custom 3D Printed Insoles and Short Foot Exercises on Foot Posture, Balance, and Gait Parameters in Individuals With Pes Planus

The primary purpose of this study is to evaluate the effects of combining custom 3D-printed medial arch-supported insoles with short foot exercises on foot posture, balance, and gait parameters in individuals with pes planus (flat feet). Furthermore, the study will investigate the impact of this combined intervention on secondary outcomes, including pain levels, health-related quality of life, and functional exercise capacity measured by the 6-Minute Walk Test.

Study Overview

• Status: Recruiting
• Conditions: Pes Planus
• Intervention / Treatment: Other: Custom 3D Printed Insoles and Short Foot Exercises

Detailed Description

Participants will be recruited through personal networks and social media platforms using a snowball sampling method. Potential candidates will be screened for pes planus in accordance with established literature protocols, utilizing the Foot Posture Index-6 (FPI-6) and the Navicular Drop Test.

Eligible individuals who meet the criteria for pes planus will undergo 3D foot scanning. Based on the obtained data, customized medial arch-supported insoles will be manufactured using 3D printing technology. Participants will be instructed to use these custom insoles in their daily lives for a total of 8 weeks. Concurrently, they will be assigned a daily short foot exercise (intrinsic muscle training) program. Each exercise repetition will involve a 5-second hold, and the entire protocol will be maintained for 8 weeks.

All clinical, functional, and biomechanical evaluations-including foot posture, dynamic balance, comprehensive gait and plantar pressure analysis (via the Zebris system), pain intensity, quality of life, and functional walking capacity-will be conducted at two time points: at baseline and at the end of the 8-week intervention period.

For statistical analysis, depending on the normality of data distribution, either a paired t-test or a Wilcoxon signed-rank test will be used to evaluate within-group changes between baseline and week 8. To determine the magnitude of the intervention effect, Cohen's d effect sizes for dependent measures will be calculated and reported alongside 95% confidence intervals.

• Study Type: Interventional
• Enrollment (Estimated): 54
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Ayse Kocak Sezgin, Phd; Phone Number: +90 5072243706; Email: ayse.kocaksezgin@ksbu.edu.tr
• Study Contact Backup: Name: Emrah Afsar, Phd; Phone Number: 5062527008; Email: emrah.afsar@ksbu.edu.tr

Study Locations

• Turkey (Türkiye)
  • Kütahya, Turkey (Türkiye)
    • Recruiting
    • Kutahya Health Science University
    • Contact: Emrah Afsar, Phd; Phone Number: 5062527008; Email: emrah.afsar@ksbu.edu.tr
    • Principal Investigator: Emrah Afsar, Phd
    • Sub-Investigator: Zeynep Sena Namaz, MSc

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged between 18 and 35 years.
• Presence of pes planus, defined as a Navicular Drop test value > 10 mm and a Foot Posture Index-6 (FPI-6) score between +6 and +12.
• Willingness to volunteer for the study and provide written informed consent.

Exclusion Criteria:

• Presence of rigid pes planus.
• Hallux valgus.
• Hallux rigidus.
• Calcaneal spur (heel spur).
• History of any neurological, cardiovascular, or systemic diseases.
• History of any orthopedic disease affecting the lower extremities.
• History of lower extremity surgery.
• Body Mass Index (BMI) ≥ 30 kg/m².

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Insole and Exercise Group; All participants in this group will receive custom 3D printed insoles and perform a short foot exercise program.

Other: Custom 3D Printed Insoles and Short Foot Exercises; The intervention consists of a combined biomechanical and active rehabilitation approach for individuals with pes planus: Custom 3D Printed Insoles: The participants' feet will be 3D scanned, and custom insoles will be manufactured using 3D printing technology. Participants will be recommended to use these personalized insoles during their daily activities for a total of 8 weeks.; Short Foot Exercises (SFE): Participants will perform a short foot exercise (foot core / intrinsic muscle) program aimed at increasing intrinsic foot muscle activation. The exercise protocol will be performed daily for 8 weeks, with each repetition held for five seconds.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Foot Posture Index-6 (FPI-6)	Assesses foot posture across 6 criteria. Total scores range from -12 (highly supinated) to +12 (highly pronated).	Baseline and 8 Weeks
Navicular Drop Test (NDT)	Assesses medial longitudinal arch height difference (in mm) between seated (non-weight bearing) and standing (weight bearing) positions. Higher values indicate increased pronation.	Baseline and 8 Weeks
Modified Star Excursion Balance Test (MSEBT)	Evaluates dynamic balance by measuring the maximum reach distance (in cm) in three directions: anterior, posteromedial, and posterolateral.	Baseline and 8 Weeks
Spatiotemporal Gait and Plantar Pressure Parameters	Evaluated using the Zebris system. Includes gait speed (m/s), cadence (steps/min), stride length (cm), stance percentage (%), and plantar pressure parameters (e.g., peak pressure, contact area).	Baseline and 8 Weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Numeric Pain Rating Scale (NPRS)	Assesses pain intensity on an 11-point scale ranging from 0 (no pain) to 10 (worst imaginable pain).	Baseline and 8 Weeks
36-Item Short Form Health Survey (SF-36)	Assesses health-related quality of life across 8 domains. Subscale scores are transformed to a 0 to 100 scale, where higher scores indicate better health status.	Baseline and 8 Weeks
6-Minute Walk Test (6MWT) and Modified Borg Scale	Evaluates functional capacity by measuring the total distance walked in 6 minutes (in meters). Perceived exertion is assessed before and after the test using the Modified Borg Scale (0-10 scale; higher scores indicate greater exertion).	Baseline and 8 Weeks

Collaborators and Investigators

• Sponsor: Kutahya Health Sciences University
• Investigators: Principal Investigator: Emrah Afsar, Phd, Kutahya Health Science University

Study record dates

Study Major Dates

• Study Start (Actual): October 26, 2026
• Primary Completion (Estimated): October 26, 2027
• Study Completion (Estimated): December 26, 2027

Study Registration Dates

• First Submitted: October 19, 2026
• First Submitted That Met QC Criteria: October 19, 2026
• First Posted (Actual): October 26, 2026

Study Record Updates

• Last Update Posted (Actual): November 5, 2026
• Last Update Submitted That Met QC Criteria: November 4, 2026
• Last Verified: November 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Talipes; Musculoskeletal Diseases; Musculoskeletal Abnormalities; Congenital Abnormalities; Lower Extremity Deformities, Congenital; Limb Deformities, Congenital; Foot Deformities; Foot Deformities, Acquired; Foot Deformities, Congenital; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Flatfoot
• Other Study ID Numbers: 3D Insole in Pes Planus; TDK-2026-365 (Other Grant/Funding Number: Kutahya Health Sciences University Scientific Research Projects Unit)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No