Diabetes damages feet quietly. The nerve that would make you limp goes first, so the wound, the infection and the collapse all arrive without pain to announce them. This site explains what is actually happening, written by a foot and ankle surgeon who treats it.
Something is wrong right now
Find the row that matches what you are looking at.
- Emergency department today
Fever, spreading redness, pus, black tissue, or a foot that is cold and dusky.
This is not an appointment. Go now.
- Seen within days
One foot hot, red and swollen, with no wound and no injury you can remember.
- Seen this week
Any open sore, however small — and especially if it does not hurt.
- Nothing wrong yet
No wound, no swelling, no color change. This is the best time to be here.
Free to download: The Diabetic Foot Care Guide. 35 printable pages from Dr. Tom Biernacki: the 30-second daily foot check, when to call and when to go to the ER, what protects a foot that has stopped warning you, and four fillable pages. No sign-up.
Coming fall 2026: the book, The Diabetic Foot Care Guide →
Five systems, not one problem
A diabetic foot complication is never a single failure. Five things go wrong at different speeds, and every ulcer, infection and collapse that follows is a combination of them.
Nerves
Protective sensation goes first. The injury still happens; the alarm does not.
Arteries
Narrowed vessels starve the tissue that has to do the healing.
Skin
Dry, stiff, fissured skin splits, and a split is an open door.
Bone
Softened bone lets the arch collapse, which builds new pressure points.
Immune response
Infection spreads further and faster before anything looks dramatic.
Start here
What diabetes does to feet
Five systems fail differently — nerves, arteries, skin, bone, immune response — and every foot problem that follows is a combination of them. The place to start if nothing is wrong yet.
Charcot foot
The bones soften, the arch collapses in weeks, and it is misdiagnosed in roughly two thirds of cases. Stages, the temperature test, and why the cast takes months.
Diabetic foot ulcers
Offloading is the treatment; dressings are support. Grading, the circulation question, and what a wound still open at six weeks is telling you.
The diabetic foot exam
What a proper examination includes, what the 10-gram monofilament tests, and why a normal ankle-brachial index can lie in a diabetic foot.
What it looks like
Drawings of the changes that matter, sorted by how urgently each one needs to be seen.
Before it becomes an ulcer
The dark spot in a callus, the blister, the small shallow sore — and the window in which they still close easily.
When a toe changes color
Red, purple, black or pale: what each color usually means on a diabetic foot, and how fast each one needs to be seen.
A wound that will not heal
It is usually being walked on, short of blood or quietly infected. What fixes each, and the myths that slow healing.
The daily foot check, in thirty seconds
- Both feet, every day, in good light — soles included, using a mirror or a phone camera if you cannot see them.
- Between every pair of toes. Damp, white, split skin there is where infection starts.
- Anything new: redness, a blister, a crack, a dark spot inside a callus, drainage on a sock.
- Compare the two feet for warmth with the backs of your hands. One foot noticeably hotter is a finding.
- Shake out and hand-check the inside of every shoe before you put it on.
Print the 30-Second Daily Foot Check (free PDF, 1 page)
The rule that prevents most of it
Nothing sharp, no corn plasters, no callus removers, no bathroom surgery, and never barefoot — indoors included. Most injuries to an insensate foot happen at home, to people being sensible about everything else.
Why this site exists
Search for almost any diabetic foot problem and the results are either a hospital page written to be unimpeachable rather than useful, or a practice page written to rank. Both leave out the part that decides outcomes: the reasoning. Why offloading beats dressings. Why a normal X-ray does not exclude Charcot. Why the certifying physician for Medicare diabetic shoes cannot be your podiatrist. Why a wound that has not closed in six weeks needs a different question, not more patience.
That reasoning is what a foot and ankle surgeon uses every day and it is almost entirely absent online. This site is an attempt to put it in front of the people it belongs to.
Browse the guides by topic
When something is wrong
Skin and nails
In Michigan?
Balance Foot & Ankle sees diabetic wounds, Charcot, at-risk foot exams and therapeutic footwear in Howell and Bloomfield Hills.