Making Custom Orthotics: From Scan to Sole

This article explores the technology used to create custom orthotics, the properties of the material used, and how patient feedback plays a role in the process.

Capturing the Foot

There are four main techniques we use to capture the shape of a foot for orthotics:

    1. Plaster Cast: A mold is taken of the patient’s foot using plaster.
    2. Foam Box and Plaster: A foam box is filled with a special foam and the patient’s foot presses into it. Plaster is then used to create a cast of the impression.
    3. Orthema Scanner: A 3D scan of the foot is captured using a specialised scanner.
    4. Direct EVA Mold: Using a special technique developed by one of our senior orthotists, we can heat EVA and mold it directly to the patients foot in a correct position.

The chosen technique depends on the patient’s foot shape, clinician preference and needs.

Foot Specifications Measured

The scan or impression captures various foot details including:

  • General shape
  • Width
  • Length
  • Arch contour and height
  • Bony prominences
  • Pressure Areas and Toe Shape

What is EVA Foam and Why is it Used?

EVA foam, or ethylene vinyl acetate, is a dense foam commonly used in shoe soles. It’s chosen for orthotics because it provides:

  • Shock absorption: EVA absorbs impact while maintaining its shape.
  • Balance between support and flexibility: It’s not too soft or too rigid, allowing for proper foot control while mimicking natural movement.
  • Durability: EVA will last for several years before needing to be replaced

Most clinics will make their Orthotics using plastic covered in synthetics or foam. We however have found this style to be less comfortable, less adjustable, more likely to slip around in the shoe (painful when you stand on the edge of one) and less tolerated by patients.

EVA strikes a great balance of comfort and correction. Fixing alignment while allowing the foot to go through much of its natural movement.

Different Densities of EVA Foam

EVA foam comes in various densities measured in millimeters of mercury (mmHg).

Orthotic clinics typically stock a range of densities (4-5) to cater to individual needs.

Factors considered when choosing density include:

  • Body weight and height: Higher density for heavier individuals for better support.
  • Activity level: More shock absorption for high-impact activities might require a lower density.
  • Pressure areas: A softer material might be used in areas with corns or calluses.

Constructing a Multi-Density Orthotic

There are three main methods for constructing orthotics with different densities:

  • Layering: Multiple EVA foam layers of different densities are glued together andshaped.
  • Milling: A block of double-density EVA foam is used. The orthotic is milled from the block, with the desired density chosen based on patient requirements.
  • Spot Reliefs: We can add areas of low density to a high density orthotic to provide spot relief to a painful area

EVA foam is flexible and can withstand bending without damage. This flexibility is crucial for orthotics to function properly within shoes.

Patient Feedback in Customisation

Patient feedback plays a vital role in customising orthotics.

While a clinician can assess foot posture, only the patient can describe their pain points. This feedback is essential for initial orthotic creation and for adjustments during review appointments.

The Manufacturing Process

Once the foot shape is captured and any necessary modifications are made the design is sent to a milling machine that creates the orthotic from the chosen EVA foam block or made by hand by our skilled orthotists.

Choosing the Right Orthotics: A Comprehensive Guide

Selecting the right orthotics can significantly affect your foot health and overall comfort.

Whether you’re dealing with a specific foot condition or just seeking better support, understanding the various options and factors involved is key. Here’s a detailed guide to help you make an informed decision.

Factors to Consider When Choosing Orthotics

Condition and Foot Shape

The type of orthotic you need depends on your specific foot condition, your age, activity level and foot shape.

If you’re looking to read about what specification of Orthotic is suitable for your condition, read our 10 Most Common Causes of Foot Pain and How They’re Treated.

What Material Orthotics Are Made Out Of

Orthotics can be made from various materials, each offering different benefits:

  • EVA (Ethyl Vinyl Acetate): A dense foam that comes in varying densities, EVA is commonly used by orthotists. It provides a balance between support and flexibility, which is essential for maintaining the foot’s natural mobility.
  • Rigid Plastics: Often used by podiatrists, rigid plastics offer firm support but can limit the foot’s natural movement and be less comfortable in the shoe. It is also less adjustable and customisable.

Advantages of EVA Material in Orthotics

  • Support and Flexibility: EVA provides a good balance between support and flexibility, allowing for natural foot mobility while still offering adequate structural support.
  • Customisability: It comes in varying densities, making it easy to customize for different levels of support and cushioning based on individual needs. It can be re-shaped multiple times.
  • Shock Absorption: EVA is known for its excellent shock-absorbing properties, which helps in reducing impact on the feet and joints during activities like walking and running.
  • Lightweight: The material is lightweight, which contributes to the overall comfort of the orthotic and reduces fatigue.
  • Durability: Despite being lightweight, EVA is durable and retains its shape and supportive properties over time.
  • Comfort: Its soft, cushioning nature enhances overall comfort, making it a popular choice for everyday wear and for individuals with sensitive feet.

Choosing between Prefabricated and Custom Orthotics

  • Prefabricated Orthotics: These are ready-made and can be a cost-effective solution for mild symptoms or general support. While they can be customised to some extent, their effectiveness may be limited compared to custom orthotics
  • Custom Orthotics: Tailored to your specific foot shape and condition, custom orthotics offer the best in stability and function. They are ideal for severe conditions or unusual foot shapes, providing personalised support where you need it most. Typically a higher cost option.

Size of Orthotics

  • Full-Length Orthotics: These extend the entire length of your shoe, providing comprehensive support. They are ideal for conditions affecting the forefoot or for use in sports shoes where stability is crucial.
  • Three-Quarter Length Orthotics: These stop at the ball of your foot, making them suitable for tighter-fitting shoes, such as dress shoes. Typically used for heel or arch-only related issues. They offer less comprehensive support but fit more easily into a variety of footwear.

The Role of Footwear

The choice of footwear can significantly impact the effectiveness of your orthotics.

Shoes with enough room and depth to accommodate the orthotic, whether full-length or three-quarter length, are essential. Additionally, the stability of the shoe itself can enhance or hinder the orthotic’s performance. Combining supportive shoes with the right orthotic ensures optimal results.

Deciding Whether to Invest in Higher-Priced Custom Orthotics

If you’re experiencing chronic foot pain or have a complex foot condition, custom orthotics may be the best option.

During an assessment, an orthotist will evaluate your foot shape, condition, and symptoms to determine the most appropriate orthotic features for you, such as metatarsal domes, medial wedges, or specific cutouts to offload pressure points.

Combining Orthotics with Other Treatments

This is plastic AFO - also known as a carbon fibre print. It is also a solid AFO.

Orthotics often work best when used alongside other treatments.

For example, if you have plantar fasciitis, your orthotic regimen might include stretching exercises or physiotherapy. Orthotics are a part of a comprehensive treatment plan aimed at relieving symptoms and improving foot function.

Choosing Between an Orthotist and a Podiatrist

While both podiatrists and orthotists can provide orthotics, their approaches and expertise can differ. Podiatrists handle a broader range of foot care issues, including nail cutting and wound care, whereas orthotists specialise in biomechanics and supportive devices.

Orthotics clinics often have in-house milling equipment and workshops, enabling them to prescribe and refine custom orthotics. In contrast, podiatry clinics may not have this equipment and therefore may offer only prefabricated orthotics.

This specialised expertise means some orthotists can provide more tailored and effective orthotic solutions. However, podiatry remains a very valid choice.

Using Insurance and Rebates for Purchase of Orthotics

Before investing in orthotics, check with your private health insurer about your coverage.

Rebates are typically available only if you have extras cover, and the extent of coverage can vary based on your specific plan. Contacting your insurer beforehand can help you understand any out-of-pocket costs.

Choosing the right orthotics involves considering your specific condition, foot shape, material preferences, and footwear compatibility. Whether opting for prefabricated or custom solutions, consulting with a professional ensures you get the support you need.

By combining orthotics with appropriate footwear and other treatments, you can effectively manage foot pain and improve your overall comfort and mobility.