What is still there, and what it is called

Cavus, adductus, varus, equinus. Residual deformity is those four separate components in whatever mix your foot ended up with, and knowing which ones you have explains most of what your foot does all day.

Written by Heath, who has lived it: casts from birth, a fusion at sixteen, the US Army, and distance running.

Four components. Open the ones that sound like your foot. Most adults have two or three to some degree, and almost nobody has all four badly.

Cavus . The arch sits too high The one people notice least and blame least, and it starts the chain. Component 12 min

The front of the foot is pushed down relative to the back, so the arch is exaggerated and not flattened. In a clubfoot (club foot, talipes) this comes from the first ray sitting lower than the rest, which tips the whole forefoot.

It is the first thing Ponseti casting corrects, precisely because leaving it in place makes everything else resist correction. In an adult foot, whatever remains of it is doing the same job it always did: concentrating your weight into a smaller area.

A visibly high arch that does not flatten when you stand

Callus under the ball of the foot and under the heel, with little in between

Shoes that feel tight over the instep

Claw or hammer shape to the toes

Poor shock absorption on hard ground

Repeated ankle rolls, because the base is narrow

Cavus is the component that responds best to a well-made orthotic, because the problem is pressure distribution and an insole can genuinely redistribute pressure. That is covered on the footwear page.

Adductus (the front of the foot points inward) The component most visible in a footprint and in a shoe. Component 22 min

Draw a line down the middle of the heel and continue it forward. In a straight foot it exits between the second and third toes. With adductus it exits well toward the little toe, because the forefoot has swung inward at the midfoot.

This is the component behind the “bean-shaped” or “kidney-shaped” appearance, and it is the one that makes shoe fitting genuinely difficult instead of merely annoying.

Both feet of an adult with treated bilateral clubfoot, photographed from above while standing barefoot on a wood floor. — **Both of mine, from above**Try the line yourself on these. Mine are bilateral, so there is no straight foot alongside to measure against, which is its own problem and the reason it took me decades to notice anything.

Degree	What you notice	Usual approach
Mild	Shoes wear unevenly, otherwise unremarkable	Nothing, or width fitting
Moderate	Visible curve, pressure on the outer border	Wide or straight-lasted shoes, padding
Severe	Difficulty fitting any shoe, skin problems on the outer edge	Custom footwear, sometimes surgical

Adductus alone is generally well tolerated. Adductus combined with varus is what puts your body weight onto the outer border of the foot, and that combination is the usual explanation for the pain patterns described on the pain location page.

Varus, the heel tilts inward The component that determines what your foot actually stands on. Component 33 min

Looked at from behind, a typical heel sits vertical or tips very slightly outward. A varus heel tips inward, so that the ground contact moves from the middle of the heel pad toward its outer corner.

This is the component that matters most functionally, because it decides the alignment of everything stacked above it. It is also the component most likely to be genuinely fixed in an adult, since it lives in the subtalar joint.

Heel and lower leg of an adult with treated clubfoot photographed from behind, standing barefoot, showing the position the heel sits in under load. — **My left heel, from behind**This is the view described above, on my own foot, taking weight. What a heel does under load is the thing to look at, and it is not what a photograph can tell you. Ask someone to look.

If it is still flexible

The heel can be brought upright by hand
It corrects when you stand on tiptoe
Orthotics and bracing can hold position
Tendon transfer is sometimes an option
Strength work has something to act on

If it is rigid

The heel will not move under your hands
No change on tiptoe
Insoles redistribute pressure but cannot realign
Correction requires bone work, not soft tissue
Fusion becomes the realistic option if it hurts

The flexible-versus-rigid distinction is the single most useful thing anyone can tell you about your own foot, and it takes a specialist about thirty seconds to establish. It is worth asking directly.

Equinus. The ankle will not bend up far enough Not really a deformity of the foot, and the one you feel every day. Component 42 min

Walking needs roughly ten degrees of upward ankle movement past neutral. Squatting and going downhill need considerably more. Equinus means you do not have it, whether because of a tight calf, a stiff ankle joint, or both.

Since the movement has to come from somewhere, the body borrows it. From the midfoot, which flattens and rolls, or from the knee, which stays bent, or from early heel lift, which is why you may push off before you should.

Cannot squat with heels flat on the floor

Heel lifts early when walking

Downhill and descending stairs feel disproportionately hard

Persistent calf tightness that stretching barely touches

Pain in the arch or midfoot rather than the ankle

Flat shoes feel much worse than shoes with a heel

That last line is the practical test worth knowing. If a slightly raised heel makes an obvious difference to how your day feels, equinus is a live component of your foot, not a historical note. And a heel-to-toe drop in your everyday shoes is a legitimate intervention rather than a cheat.

Residual is not the same as failed

The aim of clubfoot treatment has never been an anatomically normal foot. It has been a plantigrade one: a foot that puts its sole on the ground, fits in a shoe, and does not hurt. Measured against that, a foot with residual components can be a complete success.

Radiographs of well-functioning adult clubfeet routinely look worse than the person walking on them, and the reverse happens too. What matters is what the foot does across a day, not what it measures.

Here is what forty-one years of that looks like. Three scars, three operations, and a foot that has covered a lot of ground.

Left foot and ankle of an adult with treated clubfoot showing the surgical scar left by a triple arthrodesis performed at age sixteen. — **The left foot, and the fusion scar**The scar across the top is the triple arthrodesis, August 2001, when I was sixteen. Two staples went in that day and they are still in there.

Inner side of the lower leg and foot of an adult with treated clubfoot, showing the scar running from the midfoot up toward the shin left by posteromedial release surgery in infancy. — **The inside of the leg**This one runs from the midfoot up toward the shin and both legs have it, from the releases at four months old in 1985. I have no memory of getting it and I did not know what it was for until I read the operative note last week.

A flexible foot with visible deformity usually beats a straight foot that will not move.

Which leads to the one piece of advice that applies to almost everyone reading this: surgery for residual deformity is offered for pain and function. Not for the shape, not for the X-ray, and not because a component has a name. If your foot is comfortable and does what you need, having residual varus on paper changes nothing about what you should do next.

Residual deformity

Can it be corrected in adults?

Sometimes, depending on which components are involved and whether the foot is flexible or rigid. Options range from tendon transfers and osteotomies in flexible feet to fusion in rigid ones, and are chosen by what hurts and not by appearance.

Can you develop clubfoot later in life?

No. Clubfoot is congenital by definition: the foot takes that shape before birth, and a foot that was typical does not become a clubfoot later. Three things get called that afterwards and all three are different. A treated clubfoot whose correction is being lost is a relapse. A treated clubfoot that never fully corrected is residual deformity, which is this page. And a foot that turns in from something acquired, a nerve injury, a tendon failing, arthritis, is an acquired deformity that can look similar and is managed on its own terms.

Why do I walk on the outside of my foot?

That is typically residual varus and adductus together, which tilt the weight-bearing surface toward the outer border. It explains outer-edge calluses, faster wear on that side of the shoe and pain along the fifth metatarsal.

Is a stiff foot worse than a deformed one?

Functionally, stiffness usually costs more. A flexible foot with visible deformity often works well, whereas a straight but rigid foot transfers load to the knee, hip and back and tires much faster.

What is residual clubfoot deformity?

It is the part of the original foot shape that treatment did not fully correct, or that returned afterwards. In adults it is usually described as a combination of four components: cavus, adductus, varus and equinus, each present to a different degree.

Does residual deformity mean my treatment failed?

No. Complete anatomical normality was never the goal of clubfoot treatment. A functional, plantigrade, pain-free foot is, and many adults have residual deformity on examination while walking perfectly well.

What do cavus, adductus, varus and equinus mean?

Cavus is a high arch, adductus is the front of the foot turning inward, varus is the heel tilting inward, and equinus is the ankle not bending upward enough. Together they describe the classic clubfoot position.

Does residual deformity get worse over time?

The bony shape is generally stable in adulthood. What changes is flexibility and the amount of pain it produces, so the foot can feel like it is deteriorating while the underlying deformity is unchanged.

Can residual deformity be corrected in adults?

Should I have residual deformity treated if it does not hurt?

Generally no. Adult clubfoot surgery is offered for pain and function, not for appearance or for X-ray findings, and operating on a comfortable foot risks trading a working compromise for an unknown.

Sources

Where this comes from

1 The Adult Sequelae of Treated Congenital ClubfootPubMed 2 Long-Term Follow-Up of Children With a Surgically Treated ClubfootPubMed Central 3 Correcting Residual Deformity Following Clubfoot ReleasesPubMed Central 4 Late Effects of Clubfoot Deformity in Adolescent and Young Adult PatientsPubMed Central 5 Arthrodesis of the Foot or Ankle in Adult Patients With Congenital ClubfootPubMed Central 6 Clubfoot Clinical OverviewAAOS OrthoInfo

Taking it further

Shoes and orthotics →Which components a shoe can actually help with. Arthritis →What happens to the joints these components live in. Where it hurts →Map the components onto your own sore spots. Which muscles are actually weak →Four groups, and which of them training reaches. Whether the hips are involved →The association, and what the newborn check already covers.