Total contact casting and non-removable offloading

What a total contact cast is

A total contact cast is a minimally padded knee-high cast of plaster or fiberglass, molded by hand so it touches the entire sole and lower leg, often with a sole attached underneath for walking. This spreads each step’s load across the whole foot instead of onto the ulcer.⁠^[1] A close relative, the non-removable walker or “instant total contact cast,” is a ready-made knee-high boot wrapped in cast material or closed with a tie so it can’t be slipped off.⁠^[1]

Swipe sideways to see the whole drawing.

Why “can’t take it off” matters

In a study of 20 people with diabetic foot ulcers treated in removable walkers, step counters worn at the waist and hidden on the walker showed the walkers were on for only 28% of the day’s steps.⁠^[5] The offloading guideline names this the main advantage of a non-removable device: you can’t skip wearing it.⁠^[1]

Who it helps

The main use is a neuropathic ulcer on the sole of the forefoot or midfoot, such as under the ball of the foot, where the guideline strongly recommends a non-removable knee-high device first.⁠^[1] (“Neuropathic” means the foot has lost feeling from peripheral neuropathy (external site).) See diabetic foot ulcers. A cast is also used for:

• Ulcers on the sole of the heel, where the guideline suggests a non-removable device over a removable one, on very limited evidence.⁠^[1] See heel ulcers.
• Ulcers with mild infection or mildly reduced blood flow, where the guideline suggests considering one, with the device removed at least weekly so the wound can be checked.⁠^[1]
• Active Charcot foot with intact skin. The Charcot guideline recommends starting a non-removable knee-high device as soon as Charcot is suspected, and suggests a total contact cast as the first choice.⁠^[6] See Charcot foot and a red, hot, swollen foot.

When a removable device is safer

The guideline advises against non-removable offloading for heavy drainage, a moderate infection, moderately reduced blood flow (ischemia), or mild infection and mild ischemia together, since these wounds may need checking as often as daily. With severe infection or severe ischemia, treating that problem comes first.⁠^[1] So before we cast, we look for infection and check your circulation with noninvasive testing at our practice. See circulation tests for foot wounds and diabetic foot infections.

How it’s applied and changed

Dr. Efe Ozturk, a Foot and Ankle Surgeon, is board certified in wound care (FAPWH) and in podiatric medicine (DABPM). We apply total contact casts and fit locked walkers ourselves for the ulcers that need them. At a casting visit, we clean and trim the wound (see wound debridement), measure and dress it, then mold the cast to your foot. Each cast is custom-made, so it can allow for deformity or significant swelling, but it must be renewed at each visit, costs more and takes more expertise than a locked walker.⁠^[6]

In one series of 398 casts, the first cast was changed within a week by protocol, and casts stayed on for 7.7 days on average.⁠^[4] At each change, we check your skin and re-measure the wound. See wound care visits.

Cast or locked walker? The guideline accepts either, since both healed similar shares of ulcers in its review; a cast may suit a severely deformed foot.⁠^[1] In a trial of 41 people, 80% had healed within 12 weeks in a fiberglass-wrapped walker and 74% in a cast, with statistically equivalent healing rates; the walker was quicker to put on and remove.⁠^[3] Either way, we fit the device and show you how to get around safely.

What the results show

• Cast versus removable devices. In a trial of 63 people with superficial ulcers without infection or poor blood flow, 89.5% healed within 12 weeks in a total contact cast, 65% in a removable cast walker and 58.3% in a half-shoe.⁠^[2]
• Locking the walker. When 50 people were randomly assigned the same walker, either removable or wrapped with a bandage so it couldn’t easily come off, 82.6% versus 51.9% had healed at 12 weeks, and healed ulcers closed sooner in the wrapped walker (about 42 versus 58 days).⁠^[7]
• Across the trials. In a systematic review, pooled data from 14 studies with 1,083 people showed non-removable devices likely heal more ulcers than removable ones. They may lower infections but also cause more new skin sores; certainty was low to moderate.⁠^[8]

Living in a cast

• Walk less than usual. Reducing weight-bearing activity may help ulcers heal.⁠^[1]
• Use a walking aid if the cast makes you unsteady and your risk of falling is high.⁠^[1]
• Even out your legs. The guideline suggests considering a lift on the other shoe to offset the cast’s thick sole and help comfort and balance.⁠^[1]
• Keep your blood sugar in range. In 10 years of records covering 2,265 casts, complications were more likely with poorly controlled blood sugar or a BMI over 30.⁠^[9]
• Ask us about bathing, sleep, work and driving.

Risks and limits

In a large series, the author judged frequently changed casts safe, with a steady rate of minor, reversible complications.⁠^[4] The trade-offs:

• New sores. Among those 398 casts, 22 (5.5%) led to a new ulcer, and 30% of patients had one during treatment. All but one healed within three weeks, often while casting continued; one led to a toe amputation.⁠^[4] In the 10-year study, 159 of 381 patients had at least one complication, such as a new wound, infection or pain needing the cast changed or removed; the authors judged such problems may be more common than once thought.⁠^[9]
• Falls, weakness and joint strain. Long periods in a knee-high device may bring muscle weakness, falls, and knee or hip complaints from the uneven leg length.⁠^[6]
• Comfort. In the guideline’s review, people may be somewhat less satisfied with casts than with locked walkers.⁠^[1]

A cast protects the ulcer but doesn’t change the shape of your foot.

After the cast, and when surgery is the next step

After healing, the prevention guideline recommends therapeutic footwear with a demonstrated pressure-relieving effect, plus integrated foot care, to help keep the ulcer from returning.⁠^[10] We provide therapeutic shoes and custom inserts; the Ozturk Foot & Ankle diabetic foot care page (external site) has more on protective footwear. See offloading boots and footwear and keeping your foot in remission.

When non-surgical offloading hasn’t healed an ulcer under the ball of the foot, the guideline advises considering surgery, such as an Achilles tendon lengthening or removing the metatarsal head beneath the ulcer, combined with an offloading device. For an ulcer on the tip or underside of a flexible bent toe other than the big toe, it recommends a small toe-tendon release as a first-line treatment. Because these operations change the foot’s structure, they offer longer-lasting pressure relief, though surgery carries its own risks and isn’t used when blood flow is severely reduced.⁠^[1] Achilles lengthening, for example, likely increases new heel ulcers.⁠^[8] Dr. Ozturk performs these operations for the ulcers that need them. See surgery that takes pressure off ulcers.

Questions to ask

• Is my ulcer a good match for a cast, or would a locked walker suit me better?
• How often will the cast be changed, and what should I watch for in between?
• After it heals, what should I wear, and would surgery lower the chance of it coming back?

When to seek care

See us within a day or two for any foot wound that isn’t healing, especially if you have diabetes.