Reviewed for medical accuracy by Dr Evelyne Jonniaux, Medical Advisor
Last updated 17 September 2026
No trial has shown that a custom orthotic outperforms a prefabricated one. The most precise direct comparison gives a difference of 0.03 points on a pain scale. And in a Dutch primary care trial, patients managed by their GP with exercise advice did better than those referred to a podiatrist for a custom insole, on all four measured outcomes.
The questions we get asked
Custom or prefabricated?
Two meta-analyses published the same year in the same journal asked the question. Whittaker found no difference between custom and prefabricated at any time point. Rasenberg found a difference of 0.03 points, with a confidence interval running from -0.15 to 0.22. A double-blind trial in 125 patients with plantar fasciitis gives 4 points of difference at four weeks and 3.9 at eight, neither significant; its authors recommend prefabricated devices first line.
Do orthotics really relieve heel pain?
Moderately, and briefly. The reference trial compared three groups: a thin foam sham, a firm prefabricated device, and a semi-rigid custom one. At three months the only statistically solid difference is on function rather than pain, and it is worth about 8 points out of 100. At twelve months there is no significant effect on the primary outcomes.
The two meta-analyses also contradict each other on whether a medium-term effect exists at all. We flag that rather than picking the one that suits.
And the trial that is hardest to explain away?
The STAP trial randomised 185 patients between three pathways: the GP alone, a podiatrist’s custom insole, and a sham insole fitted by a podiatrist. Custom did no better than sham. And the GP alone did better than custom on pain during activity, pain on first step, the Foot Function Index, and self-reported recovery.
Can an insole help a knee or a back?
The knee is instructive. A meta-analysis finds an effect of 0.47 standard deviations when a lateral wedge is compared with nothing. It finds 0.03 when compared with a neutral insole. The apparent effect disappears as soon as there is something in the shoe. For the back, neither treatment nor prevention reaches significance.
Where do orthotics clearly work?
In preventing overuse injury, and it is the only area where the effect is clear: a 41 percent reduction in stress fracture risk. That has nothing to do with foot pain, and plain cushioning insoles show no effect at all.
What the figures say
| Finding | Figure | Source |
|---|---|---|
| Custom against prefabricated, pain | 0.03 points of difference | Rasenberg et al., Br J Sports Med, 2018 |
| Orthotic against sham at 3 months, function | about 8 points out of 100 | Landorf et al., Arch Intern Med, 2006 |
| Same trial at 12 months | no significant effect | Landorf et al., 2006 |
| GP against custom insole, self-reported recovery | against the insole | STAP trial, Br J Sports Med, 2021 |
| Lateral wedge against neutral insole, knee osteoarthritis | 0.03 standard deviations | Parkes et al., JAMA, 2013 |
| Prevention of stress fractures | risk reduced by 41 percent | Bonanno et al., Br J Sports Med, 2017 |
Two figures we could not source. “90 percent of plantar fasciitis resolves within a year”: the only long prospective cohort we found reports 80.5 percent of patients still symptomatic at one year, and a mean duration of 725 days among those who did recover. And “70 percent of people have a gait fault to correct” traces back to no publication, in any formulation.
What Noria Health does, and does not do
We organise a podiatry and foot orthopaedics consultation with a specialist team near Brussels, clinical examination and gait analysis included, and confirm feasibility within 24 to 48 hours.
We do not prescribe orthotics remotely, we do not assess a foot from a photograph, and we do not replace the podiatrist who follows you.
Who reviewed this page
Noria Health editorial team.
See also: all our articles on posturology and podiatry.
Have your case reviewed. Noria Health arranges a specialist consultation near Brussels and confirms feasibility within 24 to 48 hours. Open a case.