Footwear Modifications
Reviewed by Andrew Schox, BSc(Hons) PGradDipPod MPod, October 2026
Footwear modification means changing a shoe you already own, usually on the outside, rather than making a new one. Common changes are a rocker sole, a raise for a short leg, a wedge or flare, or a socket for a calliper. The aims are to ease pain, reduce pressure, protect your foot and help you walk more comfortably. It is best known for helping prevent foot ulcers coming back in adults with diabetes and numb feet. Benefit depends on the shoe being suitable and on wearing it often.
What is it?
Footwear modification means changing a shoe you already own, usually on the outside, rather than making a new shoe. Your podiatrist or an orthotic service (a service that makes and fits devices such as shoe supports) can advise on what is possible.
The common changes are:
- A rocker sole: a curved sole that reduces pressure on the balls of your feet.
- A raise: a built-up sole, used where one leg is shorter than the other.
- A wedge or flare: an addition that shifts your weight line, which changes how you stand and walk.
- A calliper socket: a fitting in the heel that lets the shoe be used with a calliper (a leg brace).
The aims are to ease pain, reduce pressure, protect the foot, and improve comfort, stability and the way you walk. These changes alter the pressure under your foot and how your joints move.
What is it used for?
The best-supported use is stopping foot ulcers (open sores) from coming back in adults with diabetes and reduced feeling in their feet. Therapeutic footwear (specially prescribed shoes) can lower the chance of a new ulcer in people who have had one. Rigid-soled footwear has done better than shoes with softer, semi-rigid soles. Even so, the strength of this evidence is rated low, and not every trial agrees.
Other uses have less support:
- Big toe joint stiffness (hallux rigidus): in adults, shoe inserts reduced pain. A small 3 mm support under the joint at the base of the big toe increased how far the big toe could bend up.
- Overuse injuries: rocker-bottom shoes appear to help by taking pressure off the front of the foot.
- Achilles tendon pain (in the middle of the tendon): in one trial, heel lifts reduced pain more than calf exercises. The difference was small, not beyond what counts as a meaningful change.
- Knee osteoarthritis: a wedge that tilts the foot (a lateral wedge insole) did not reduce pain compared with a flat insole. It does reduce load on the knee. Wedges combined with arch support may improve pain and function, but this is less certain.
For a shorter leg, a raise is the usual approach. How well this works hasn't been clearly shown yet, so ask your clinician what to expect.
Is it right for me?
The group with the clearest benefit is adults with diabetes who have had a foot ulcer, or who are at high risk of an ulcer or other diabetes-related foot problems. For people with diabetes, footwear is matched to your ulcer risk level and the shape of your feet, and checked by a team of health professionals.
Footwear alone is not the first choice for healing an active ulcer on the sole of the forefoot or midfoot in diabetes. The guideline puts a non-removable knee-high offloading device first (a boot or cast-type device that you can't take off). If one isn't available, fitted footwear with felted foam is a third-choice option. If an ulcer doesn't heal with non-surgical offloading, surgery may be considered.
Not every shoe can be adapted. Shoes that suit are:
- in good condition, without much sole wear
- comfortable and already worn in
- enclosed, with a secure fastening (laces or hook and loop)
- built with a firm sole and heel unit
- low in the heel, no higher than 3 cm, with no taper and a heel base as wide as the shoe
Shoes with air bubbles or gel inserts in the heel, thin soles, stitching through the sole, or soles with hollows, cut-outs or busy tread patterns are not suitable.
If you are looking for answers for a child, don't assume the findings here apply. Ask for an individual assessment.
What happens?
It starts with choosing a shoe that can be adapted. Bring comfortable, well-fitting shoes to your appointment. Then the adaptation is added to the outside of the shoe by the orthotic service or footwear technicians. Please don't try to modify shoes yourself.
Before it is done, ask what the change is meant to achieve, such as pain relief, pressure relief or making up a leg length difference.
For people with diabetes, the footwear is prescribed to suit you. Rigid-soled footwear with layered insoles that match the shape of your foot lowers the chance of an ulcer coming back. Your clinician aims to bring pressure under your foot below 200 kPa, or to reduce it by 30 per cent or more. This is for your clinician to set and check.
For knee osteoarthritis, wedges of 5° to 15° have been used. Steeper wedges are often harder to put up with.
How many visits you need isn't clear, and services set their own schedules. Ask how often your footwear will be reviewed.
How well does it work?
The clearest benefit is in adults with diabetes, numb feet and a healed ulcer. Most of the benefit shows in the first months. Custom in-shoe supports based on pressure measurements led to fewer ulcers coming back than standard supports, and this was already clear at 180 days.
Some results are less clear. One trial of therapeutic shoes with cork or polyurethane inserts found no significant extra benefit over usual footwear, and its authors suggested careful foot care by your health team may matter as much as the shoes. In another, lowering pressure by about 20 per cent alone wasn't enough to reduce ulcers. Benefit depends on both taking pressure off the foot and actually wearing the shoes.
Results for rocker soles in diabetes are mixed. In one comparison, ulcers came back in 64 per cent of people with a semi-rigid rocker sole and 23 per cent with a rigid one. Another found that changing the rocker design made no difference.
Changing pressure or joint movement doesn't always mean you will feel better. Most of what is known comes from adults with diabetes and numb feet, and many results are pressure measurements rather than pain, function or ulcers. Don't expect the same results for other conditions or for children.
Risks and side effects
Serious problems are uncommon, but there are things to watch for:
- Rubbing or pressure. New footwear can rub or press and cause skin discolouration, especially in people with diabetes. Blisters and new pain in the lower back, hips, knees, feet or ankles can also happen. In one trial, these happened at a similar rate with heel lifts and with calf exercises.
- Changes in how you move. Rocker soles can change how your joints move and how you walk. In adults with big toe stiffness, rocker-sole shoes reduced hip movement and changed walking pattern.
- Wedges. A wedge with no extra support can tilt the ankle more. A version with support under the arch reduced this and was more comfortable.
- Heel lifts. For Achilles tendon pain, use a lift in both shoes so your legs stay level.
- Forcing a correction. Trying to force a severe deformity into a corrected position with a brace or shoe can create pressure points, pain and skin breakdown.
Footwear only protects you when you wear it. In one study, about 29 per cent of steps were taken without prescribed footwear.
Afterwards
Wear new or adapted shoes for short periods at first, so you can check they aren't causing rubbing or pressure marks. Build up gradually.
If you have diabetes or reduced feeling in your feet:
- Check your shoes before putting them on each day. Look for sharp objects such as pins, nails or glass through the sole, and tap and feel inside for small objects.
- Check the skin of your feet daily.
- Don't take out your insoles unless you have been told to.
- Wear your therapeutic footwear whenever you are on your feet.
Prescribed footwear works best when worn for at least 60 to 80 per cent of the time you are active. People wear it less indoors and on weekends, so these are the times to watch. If your footwear is uncomfortable or you don't like how it looks, tell your clinician. Those are common reasons people stop wearing it, and they can often be fixed.
When to see a podiatrist
Book an appointment if
Book an appointment with your podiatrist if your new or adapted shoes rub, give you blisters, cause new pain in your feet, ankles, knees, hips or lower back, or feel uncomfortable or unstable. If your skin looks discoloured from rubbing or pressure, contact your orthotic service or foot clinician straight away. If you have diabetes, reduced feeling in your feet or poor circulation, get a foot check from your podiatrist or a foot protection service before relying on modified shoes.
Seek prompt assessment if
If you have diabetes or reduced feeling in your feet and you notice an ulcer, a blister that breaks the skin, skin breakdown, a sore that isn't healing, signs of infection such as redness, warmth or a fever, or a foot that is hot, swollen or changing shape, this needs urgent medical assessment: see your GP today, or go to an urgent care clinic or the nearest emergency department. Don't wait to see whether it settles, and don't rely on shoe changes alone. 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.
Frequently asked questions
Can I adapt my shoes myself?
It's best not to. Shoes need to be suitable, and the change needs to be made and fitted properly to do what it is meant to do. Ask your podiatrist or orthotic service. New shoes can be adapted too, as long as you have tried them on first and they are comfortable.
Why do I need to wear therapeutic footwear indoors?
People tend to take more steps at home than away from it. Going barefoot, or wearing socks or slippers, leaves your feet exposed to injury, and slippers don't protect your feet well enough. If you have diabetes, wear your prescribed footwear whenever you are on your feet.
Will footwear changes fix a knee or foot problem on their own?
Usually not on their own. For knee osteoarthritis, a wedge insole by itself shouldn't be expected to relieve pain. Ask your clinician how footwear changes fit with other care, such as orthoses (shoe inserts), exercise and foot care.