3D-Printed Vs. Prefabricated Foot Orthoses in Functional Pes Planus

Brayden Jensen, MSPO

American Orthopedics

Creation Date 9/5/2025

Re-assessment Date 2/20/2026

Clinical Question

In adults with functional pes planus, do custom 3D-printed foot orthoses compared to standard prefabricated EVA insoles or no orthoses improve biomechanical outcomes and user comfort during walking?

Background

Functional pes planus is a common condition characterized by the collapse of the medial longitudinal arch during weight-bearing, often leading to altered gait mechanics, discomfort, and increased risk of musculoskeletal issues. Traditional orthoses have been used to support the arch and improve function, but recent advances in 3D printing offer customizable, patient-specific solutions that may enhance outcomes^1,2. Thermoplastic polyurethane (TPU) materials used in 3D printing vary in mechanical properties, which can influence orthotic performance and durability³. The purpose of this analysis was to understand the clinical efficacy and mechanical reliability of these innovations which are essential for evidence-based implementation.

Search Strategy

Research studies that pertain to the field of orthotics that focuses on 3D printed Foot Orthotics.

Databases Searched: PubMed (NIH), MDPI, JPO

Search Terms: (3D-Print OR 3D-Printing OR TPU) AND (Foot Orthotic OR Foot Orthosis OR Foot Orthoses OR Insole) AND (Ples Planus OR Flatfoot OR Flat Feet)

Inclusion/Exclusion Criteria: Adults aged 18–65 with flexible flatfoot who can walk independently, and complete gait or comfort assessments were included. Individuals with rigid flatfoot, neurological or musculoskeletal gait impairments, recent foot surgery, or material sensitivities were excluded. One study did not involve human participants and therefore does not contribute to inclusion/exclusion criteria.

Synthesis of Results

Hsu et al¹ conducted a small clinical study involving adults with functional pes planus and found that all three types of 3D-printed insoles tested improved navicular height and ankle dorsiflexion angles while also increasing subjective comfort ratings¹. Among the designs, the medial wedge provided the greatest arch support, although changes at the knee joint were minimal¹. The study was limited by its short testing duration and small sample size, which restrict the strength of its conclusions¹.

In contrast, Iacob et al² emphasized the material science perspective by evaluating the flexural fatigue performance of thermoplastic polyurethane (TPU) insoles through laboratory testing rather than human trials². Their results demonstrated that TPU 95A had superior fatigue resistance and flexibility, whereas TPU 64D was stiffer and more prone to brittle failure². These findings are valuable for guiding material selection in orthotic design, though the absence of clinical validation leaves uncertainty regarding real-world patient outcomes².

Özgün et al³ contributed a single-subject case report that highlighted the potential clinical benefit of custom 3D-printed insoles in an obese adult with pes planus³. Compared with prefabricated ethylene-vinyl acetate insoles, custom devices reduced heel pressure, redistributed plantar loading, and improved comfort³. Although the report provides early support for personalized additive manufacturing in orthotic care, its generalizability is limited by the case-based design and restricted sensor coverage during gait assessment³.

Clinical Message

Custom 3D-printed foot orthoses, particularly those using TPU 95A and medial wedge designs, show promise in improving arch support, gait mechanics, and user comfort in adults with functional pes planus^1,2,3. While early evidence supports their biomechanical and subjective benefits, clinicians should be cautious due to limited long-term data and small sample sizes. Implementation should prioritize an individual assessment and consider material properties to optimize orthotic performance.