Custom Foot Orthoses

What is it?

Custom foot orthoses are shoe inserts made for your foot only. Your podiatrist takes the shape of your foot with a plaster cast, a digital scan, or a drawing or mould. The insert is then made to suit that shape and your shoes.

They are thought to work in two main ways. Some change how your foot moves, which can reduce pain and help it work better. Others take pressure off a sore area and spread it more evenly across the sole.

Testing shows orthoses can do this. They increased the area of the sole in contact with the shoe by an average of 17.4 per cent. They also lowered the peak pressure across the sole by an average of 22.8 per cent, compared with shoes without orthoses.

Being custom-made doesn't by itself guarantee a better result. For people with diabetes, a custom insole did not lower foot pressure more than an off-the-shelf one. The design matters as well as the fit.

What is it used for?

Preventing foot ulcers in people with diabetes. This is the best-supported use. Guidelines recommend considering custom-made footwear, custom orthoses or toe orthoses for adults with diabetes who have a foot deformity or an early sign of skin damage. Special footwear with custom insoles can reduce the chance of an ulcer coming back, when the pressure under the foot is brought down enough. The proof is not strong, though, so results can't be promised.

Flexible flatfoot. This is a low arch where the foot can still move freely. In adults, orthoses reduced pain more than no orthoses or fake ones, both at rest and when walking. In children the results are mixed. Some children had less pain after a year, and others had no change in pain, movement skills or how they felt about themselves. Insoles, with or without exercise, reduced pain in children and young adults overall.

Long-lasting foot and leg pain in adults. Computer-designed and made insoles (called CAD/CAM insoles) reduced pain and improved foot function and foot health within 4 weeks. The benefit was still there at 12 weeks.

Heel pain (plantar fasciitis). Orthoses may be a promising treatment that doesn't involve surgery. They reduced pain and disability, though the evidence is limited.

Other uses. Health information often lists calluses, bunions, tendon pain, repeated ankle sprains, stress fractures, shin splints, and knee, hip and lower back pain. How well orthoses work for these isn't clear yet. Don't assume a benefit seen for one problem applies to another.

Is it right for me?

Your podiatrist may suggest orthoses if you have a long-lasting foot or leg problem that gets in the way of how your feet work. See a podiatrist or other trained clinician for this. Don't choose a custom device on your own.

Orthoses are most strongly backed for adults with diabetes who have a foot deformity, an early sign of skin damage, or a risk of ulcers coming back. If you have diabetes, ask your podiatrist or diabetic foot team how likely you are to get ulcers and whether custom footwear or insoles suit you. Your plan should match your risk level and foot shape, and a team of health professionals should check it.

Orthoses probably help little if you have a rigid flatfoot, where the foot can't move freely. Everyone responds differently, so your podiatrist should tailor the plan to you rather than rely on averages.

If you have diabetes, reduced feeling in your feet or poor blood flow, orthoses must be prescribed and fitted by a trained clinician. Before any device is prescribed, you should talk through its benefits and risks. If you don't want a recommended device, say so and ask about other options.

What happens?

Your podiatrist starts with a detailed assessment. They look at any existing foot problems, the shape and movement of your feet, how far your joints move and how strong your muscles are. They check how your bones sit when you stand, and watch how you walk. They also ask about your shoes, your work and your lifestyle.

Next, the shape of your foot is captured. Your podiatrist may use a plaster cast, a digital scan, or a drawing or mould. For computer-designed insoles, a direct foot scan was linked to better satisfaction, more consistent wear and fewer adjustments than a foam-box cast. Pain, function and foot health improved just as much with either method.

For people with diabetes, the design is more specific. Arch shaping, extra padding behind the ball of the foot and cut-outs under sore spots can all lower pressure. Measuring the pressure under your foot directly, rather than relying on foot shape and judgement alone, can improve the result.

There is no set number of appointments. Ask when your review visit will be.

You then build up wear slowly, so your skin and body can adjust. Your podiatrist or orthotist (a specialist who makes orthoses) will give you a schedule. One common approach is to add about an hour a day, with no sport until they are comfortable to walk in all day.

How well does it work?

Orthoses work best for some people and groups, and not for others. Pain relief is the best-supported benefit. Adults with flexible flatfoot and adults with long-lasting foot and leg pain have had clear pain reductions. Results in children and for heel pain are less certain.

In one group, Air Force recruits, orthoses gave no clear benefit for lower limb pain or quality of life. Only about half wore them most of the time, mainly because they were uncomfortable. Comfort and consistent wear matter a lot.

There is a large amount of variation in how people respond. Your result may be better or worse than the average.

Risks and side effects

Orthoses are generally low risk, but they can take getting used to. Mild aching or tiredness in your feet, knees, hips or lower back is common at first. This should ease as you build up wear.

Sometimes one spot rubs or aches, for example under the arch or in the front of the foot. These problems cleared up once the podiatrist reviewed and adjusted the insole. If you have discomfort, try wearing them for a shorter time the next day.

Pain is different from mild aching. If your orthoses become painful, take them out until the pain settles. Then start the wear-in again from the beginning. If the pain continues, go back to your podiatrist or orthotist. Don't keep wearing a device that hurts. Discomfort is the main reason people stop wearing them.

If you have diabetes, foot treatments can cause harm if they aren't done properly, so only a trained health professional should fit them. Check your feet and your shoes before and after each use while you wear them in. Look for early signs of skin damage, injury or inflammation.

Afterwards

Give your orthoses time. Improvement can take months, especially for a problem that has built up over months or years. Keep wearing them as advised, and tell your podiatrist early if comfort is a problem.

Keep your review appointments, especially if you have reduced feeling in your feet. If you have diabetes, your feet should keep being checked for loss of feeling and poor blood flow. This is done once a year if your risk of ulcers is very low, and more often if your risk is higher.

If your pain isn't improving or is getting worse, go back to your podiatrist rather than keep wearing the orthoses and hoping for the best.

When to see a podiatrist

Book an appointment if

Your orthoses stay painful or uncomfortable after you've taken them out and restarted wearing them slowly. Your pain isn't improving or is getting worse. Discomfort is stopping you from wearing them. You have a long-lasting foot or leg problem and want to ask your podiatrist whether orthoses might suit you. You have diabetes and want to know whether custom footwear or insoles suit your level of risk.

Seek prompt assessment if

If you have a foot wound or infection and you also feel very unwell, with confusion or slurred speech, severe shivering or muscle pain, severe breathlessness, mottled or discoloured skin, or little or no urine, this could be sepsis: call your local emergency number. If you have diabetes and your foot becomes painful or rapidly swollen, or you feel unwell, see your GP or another doctor today, or contact your podiatrist or diabetic foot team straight away. Don't wait for a scheduled appointment. The same applies if you have diabetes and notice a wound, an open sore, a cut, a blister or a break in the skin that isn't healing, redness, swelling, a hot foot or any other sign of infection. If your GP can't see you today, go to an urgent care clinic or an after-hours GP. If you think you may have torn your Achilles tendon (the thick cord at the back of your ankle), see your GP or another doctor today. If you have any other new foot or leg symptom that keeps going or gets worse, see your podiatrist or GP without delay.

Frequently asked questions

Can I just buy insoles from a shop instead?

Ready-made insoles are usually foam and can be adjusted to fit. Custom ones are made for your foot and your shoes. Ask your podiatrist why they suggest a custom device for your problem, and what else, such as exercise or shoe changes, is part of the plan.

What should I bring to my appointment?

Bring the shoes you wear most often, and tell your podiatrist about your work and any sport you play. These shape the prescription. Ask how much the orthoses will cost and how long they take to make, and when your review visit will be.

How will I know if they're working?

Agree with your podiatrist how you will judge progress, such as pain when walking, and when it will be reviewed. Results build over weeks to months, so judge them over that time rather than in the first few days.

Further reading

• Orthotics Department NHS
• Orthotics - OrthoInfo - American Academy of Orthopaedic Surgeons OrthoInfo (American Academy of Orthopaedic Surgeons)
• Insoles (Foot Orthoses) NHS
• Offloading insoles NHS