What does plantar pressure have to do with diabetic foot ulcers?

How big is the problem?

The figures are worse than most people outside diabetes care expect. A 2023 review in Diabetes Care (McDermott et al., 46(1):209–221) reports a lifetime risk of foot ulceration of 19–34% among people with diabetes. Of ulcers that heal, 65% recur within three to five years. Lifetime incidence of amputation is around 20%. Five-year mortality after a diabetic foot ulcer is reported at 50–70%.

That last number is the one that reframes the condition. A foot ulcer is not a skin problem with a long healing time. It is a marker of systemic disease severity, and the outcomes attached to it are comparable to serious cancers.

Why pressure, specifically?

Two things have to go wrong together. The first is peripheral neuropathy: the loss of protective sensation that normally makes you shift your weight, adjust your gait, or take a shoe off when something is rubbing. That feedback loop operates continuously in a healthy foot and almost entirely below conscious attention.

The second is mechanical loading. Walking concentrates force on particular areas — commonly the forefoot under the metatarsal heads, the heel, and any area deformed by previous damage. In a foot with intact sensation, a hotspot announces itself. In a foot without it, the same loading repeats step after step, day after day, until the tissue underneath breaks down.

Neither factor alone is usually enough. Together they produce an injury that is fully mechanical, entirely predictable in hindsight, and invisible to the person it is happening to.

What the guidelines say about offloading

The IWGDF publishes separate guidelines on prevention and on offloading, both updated in 2023. In prevention, reducing elevated plantar pressure is a recognised intervention for people at risk (Bus et al., IWGDF Prevention guideline). In treatment, for a plantar forefoot ulcer, the first-choice intervention is a non-removable knee-high offloading device — the word non-removable doing a great deal of work, because a removable device is only worn as often as the patient chooses to wear it.

We deliberately do not publish the guideline’s numeric in-shoe pressure targets here. Those thresholds are defined for validated, calibrated in-shoe measurement systems with specified sensor dimensions, and quoting them alongside a consumer device would invite the reading that the device measures against them. It does not.

Why pressure is hard to measure outside a clinic

Plantar pressure measurement has existed for decades, on pressure platforms and with research-grade in-shoe systems. What it has almost always been is a snapshot: a set of steps, taken in a clinic, on a known surface, in one pair of shoes, while someone watches.

The loading that causes an ulcer does not happen in that room. It happens over the ten thousand steps taken in the following fortnight, in the shoes the person actually wears, on their own stairs, at their own pace, when they are tired. There is a genuine gap between where the measurement happens and where the damage happens.

What Stride One measures here, and what it does not

Stride One records how load is distributed across ten zones of each foot, continuously, in ordinary shoes. Each zone is shaded relative to the other nine zones on the same foot — so it shows where pressure concentrates on that foot and how that pattern changes over weeks, rather than giving a calibrated absolute reading in kilopascals.

That distinction matters and we would rather state it than blur it. Stride One does not measure calibrated absolute pressure, and device-specific accuracy against a reference system has not yet been demonstrated. It does not measure skin temperature, which is the parameter the Charcot-detection literature is built on. It does not detect, predict or prevent ulceration, neuropathy or Charcot foot, and it is not a substitute for foot examination, screening or specialist care.

If you have diabetes and any loss of sensation in your feet, the things that are known to help are regular professional foot checks, appropriate footwear, and acting quickly on anything that looks wrong. A record of how load is distributed is information to bring to those conversations, not a replacement for them.

What Stride One does and does not do

Stride One is a monitoring device. It records how load is shared between the feet, how the foot rolls through each step, and how pressure is distributed across the zones of each foot. It gives you, and anyone you choose to share it with, a record of how those things change.

It does not diagnose anything, detect any condition, predict any outcome, or tell you what to do about what it shows. It does not measure skin temperature, gait speed, step length, stride length or step width. It does not replace an appointment, an examination or your clinician’s judgement.

Sources

• McDermott K et al. Etiology, epidemiology, and disparities in the burden of diabetic foot ulcers. Diabetes Care 2023;46(1):209–221.
• Bus SA et al. IWGDF guideline on the prevention of foot ulcers in persons with diabetes, 2023 update.
• IWGDF guideline on offloading foot ulcers in persons with diabetes, 2023 update.

Read next