DIABETIC FOOT SYNDROME

Diabetic foot syndrome – when the foot stops warning you

Diabetic foot syndrome covers the changes to the foot that arise after many years of diabetes mellitus. Two kinds of damage are behind it, alone or together: damage to the nerves (neuropathy) and damage to the blood vessels (angiopathy). The nerves no longer register pressure, pain and temperature reliably; the vessels supply the tissue with less oxygen.

It is the combination that creates the real problem. A pressure point that would otherwise hurt – and force a change of shoes – goes unnoticed, and at the same time heals less well. About one person in ten with diabetes develops the syndrome in the course of the illness. Recognised early, it can be kept under control in most cases.

How does diabetic foot syndrome develop?

It almost always begins with a small, unnoticed injury: a pressure point under the ball of the foot, a rubbed spot on a toe, an ingrown nail. Because protective sensation is missing, walking continues – and the irritated patch of skin becomes an ulcer.

Loss of protective sensation – pressure and pain are no longer felt
Calluses that pass the pressure on to the tissue beneath
Shoes that are too tight or unsuitable, and walking barefoot outdoors
Deformities such as claw toes or a flattened arch
Reduced eyesight, which makes daily checks harder
Smoking and persistently high blood sugar

Symptoms

Diabetic foot syndrome often does not hurt – which is precisely what makes it dangerous. It shows itself in what you can see and feel.

Numbness

The foot feels furry; temperature and pressure are registered less well

Pressure points

Calluses, blisters or open areas on the ball, heel and toes – often without pain

Swelling

A foot swollen, red and warm on one side only is a warning sign

When not to wait

A foot that suddenly becomes swollen, red and warm – often without pain – may be a Charcot foot. Bones and joints collapse unnoticed, and the arch of the foot can sink within a few weeks.

The same applies to an open area that has not become smaller after a few days, to a fever, and to a wound that smells. In these cases every day counts: please come at short notice rather than waiting for your next routine appointment.

Treating diabetic foot syndrome

Treatment has an aim that goes beyond the wound itself: to take the pressure off the place where it arises. As long as the same load keeps falling on the same spot, no wound heals for good. Relieving the pressure, treating the wound and – where circulation is poor – establishing whether the vessels can be reopened therefore come first.

If the pressure remains despite footwear and insoles because a bone sits in the wrong place, it can be moved surgically. We work minimally invasively wherever possible: through openings a few millimetres wide, placed away from the wound.

Treatment options

Relieve the pressure first, correct second – for as long as possible without a large incision

Non-surgical

Footwear that takes the pressure off

Protective diabetic shoes, custom-made shoes and insoles spread the load so that the vulnerable spot no longer carries it.

Non-surgical

Orthosis and total contact cast

For deep or persistent wounds, a bivalved orthosis or a total contact cast takes the foot out of weight-bearing altogether.

Surgical

Distal minimally invasive diaphyseal osteotomy (DMDO)

Through an opening a few millimetres wide, the metatarsal bone is divided. Its head moves upwards and backwards, and the pressure under the wound falls. The incision lies away from the wound.

Surgical

Correction of toe deformities

Claw and hammer toes create pressure peaks at the tip and at the middle joint. Corrected before the skin breaks, the wound never forms in the first place.

Surgical

Removal of prominent bone edges

Prominent edges of bone can be taken down through keyhole technique, without opening the skin above them over a wide area.

Surgical

Stabilisation of a Charcot foot

Where the arch has collapsed, plates and screws rebuild the foot so that it can bear weight and fit into a shoe again.

Frequently asked questions about diabetic foot syndrome

Why do I not notice the wound?

Nerve damage takes away the foot’s protective sensation. A pressure point that would otherwise be obvious at once goes unnoticed – sometimes until it becomes infected. That is why we recommend looking at your feet every day, using a mirror or asking a relative for help if need be.

How often should my feet be checked?

Where the findings are normal, once a year is usually enough. If the nerves or vessels are already damaged, or there has been a wound before, shorter intervals make sense. We agree the rhythm together with your diabetes specialist.

Do I have to wear special shoes?

Not always. As long as the foot is unremarkable, wide seamless shoes with a soft sole are often enough. Once there are calluses, deformities or a healed wound, custom-made footwear is the most effective protection against the next one.

Is surgery not risky with diabetes?

Operations on the diabetic foot need preparation: blood sugar, circulation and any infection have to be right. That is exactly why we operate minimally invasively and away from the wound wherever we can – the openings are a few millimetres wide and the bone is not exposed.

Am I at risk of amputation?

The worry is understandable, and it is the reason we relieve pressure early and consistently. What decides the outcome is how quickly a wound is recognised and taken out of loading, and whether the circulation is sound. The earlier that happens, the less often deep infection follows. So please come once too early rather than once too late.

What does my blood sugar have to do with it?

Persistently high readings damage nerves and vessels further and slow wound healing down. Managing blood sugar is therefore part of treating the foot. It stays in the hands of your diabetes specialist – we coordinate with them.

Our foot specialists

Experienced specialists in diabetic foot syndrome and foot surgery

Prof. Dr. med. Alexander Mehlhorn

Consultant in Orthopaedics and Trauma Surgery, specialist in foot and ankle surgery