Semirigid insole for correcting flexible flatfeet

Immediate Effect of a Semirigid Foot Insole on Radiological Foot Angles in Flexible Pes Planus

This test tries a semirigid foot insole to see if it improves X-ray foot angles in adults 18–35 with asymptomatic flexible flatfeet.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 30 (estimated)
• Ages: 18 Years to 35 Years
• Sex: All
• Sponsor: Cairo University (other)
• Locations: 1 site (Giza)
• Trial ID: NCT07389343 on ClinicalTrials.gov

What this trial studies

This single-site interventional study will enroll 30 adults aged 18–35 with asymptomatic flexible pes planus confirmed by the navicular drop test and the Foot Posture Index. Each participant will have weight-bearing anteroposterior and lateral foot X-rays taken once standing barefoot and once standing on a semirigid insole, with angles measured manually using a ruler and protractor. People with symptomatic pain >3/10, foot osteoarthritis, structural deformities, prior foot fractures or lower-limb surgery, ligament tears, systemic inflammatory diseases, or neurological disorders are excluded. The trial compares radiographic angle differences between barefoot and insole conditions to see if the insole produces immediate alignment changes.

Who should consider this trial

Good fit: Adults 18–35 with asymptomatic flexible pes planus confirmed by NDT and FPI, BMI ≤29.9 kg/m², and pain ≤3/10 are ideal candidates.

Not a fit: People with symptomatic flatfoot (pain >3/10), radiographic osteoarthritis, structural foot deformities, prior foot fractures or lower‑limb surgery, ligament tears, systemic inflammatory diseases, or neurological conditions are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, the insole could improve weight-bearing foot alignment on X-ray and potentially reduce the chance of future symptoms or need for more invasive treatments.

How similar studies have performed: Foot orthoses are commonly used and some studies report symptomatic or alignment improvements, but radiographic evidence for immediate angle correction with semirigid insoles is limited and mixed.

Eligibility criteria

Inclusion Criteria:

1. Asymptomatic people with flexible pes planus. If the pain is greater than 3 out of 10 on the visual analog scale in the last 3 months, the patient is considered to have symptomatic flat feet (Mahdiyar et al., 2021).
2. Aged 18-35.
3. BMI max 29.9 kg/cm².

Exclusion Criteria:

1. Osteoarthritis of the joints of the foot (excluded by x-ray).
2. Foot Deformities (e.g. Hallux Valgus)
3. Old fractures of the foot.
4. Previous injuries to the ankle.
5. Previous surgeries to the lower limb. 6. Calcaneal Spur. 7. Foot and ankle ligaments tear.

8- Systemic diseases such as rheumatoid arthritis. (Gouty arthritis, autoimmune disease) 9. Neurological diseases.

Where this trial is running

Giza

• October 6 University Hospital — Giza, Egypt (RECRUITING)

Study contacts

• Principal investigator: Fatma Elzahraa A ElBayomi, MSc degree — Cairo University
• Study coordinator: Fatma Elzahraa A ElBayomi, MSc degree

Conditions: Flexible Flatfoot or Pes Planus, "Foot insole" and "Flexible flatfoot" and "radiological foot angles"