Prevention is key

Approximately one in every ten people with diabetes develops diabetic foot syndrome (DFS). PD Dr. med. Alexander Mehlhorn, a foot specialist from Munich, Germany, is in no doubt that many foot ulcers can be avoided through the use of foot orthoses at an early stage.

“Unfortunately most of my patients only come to me once the horse has bolted so to speak, i.e. when they already have an open foot ulcer,” PD Dr. med. Alexander Mehlhorn says. The specialist in orthopedics and trauma surgery, who has been a consultant at the Center for Foot and Ankle Surgery at Schön Klinik München Harlaching in Germany since November 2015, primarily treats patients with diabetes or conditions associated with diabetes. “Diabetic patients with neuropathy are at particular risk. The nerve damage means that those affected don’t feel pain, so they simply don’t notice pressure points or chafing.” Wounds and ulcers don’t heal as well in people with diabetes. If this then leads to a bacterial infection and is not treated promptly, the surrounding tissue including the bone can also become infected. This can result in sepsis, massive deformation, or amputation in extreme cases. The amputation risk for a diabetic is up to 25 times higher than that of a non-diabetic. PD Dr. Mehlhorn does everything in his power to treat the problem before it gets to the amputation stage, because preserving the extremities is a top priority.

Relieving pressure – in a conservative and minimally invasive way

If a patient with a foot ulcer comes to see him, the specialist starts by looking for the cause. “The key question is: why does the patient have this ulcer? Is decreased perfusion the cause? Or has the ulcer been caused by mechanical pressure, as is the case with the majority of my patients? Are there any protruding bones or misalignments which are contributing to this ulcer?”
PD Dr. Mehlhorn can identify a neuropathic pathogenesis in his patients from the characteristic shape of the feet alone: “The typical diabetic neuropathic foot has an extremely pronounced longitudinal arch, frequently developing into pes cavus. Hyperextension in the MTP joints and PIP joint flexion contractures cause claw toes and hallux flexus of the big toe. This combination of factors means that there are already a number of places where an ulcer will typically develop,” the foot specialist emphasizes. Ulcers underneath the heads of the metatarsal bones are one example. “Even the fact that many diabetic neuropathic feet have such a high instep means that there’s a lot of pressure underneath the heads of the metatarsal bones due to the steep angle of the metatarsals. These ulcers are treated conservatively to begin with – by providing appropriate wound care and foot orthoses with soft cushioning,” PD Dr. Mehlhorn explains. However, if there is no improvement after a certain period of time, he has no doubts about recommending surgical intervention. “One option is small , minimally invasive metatarsal osteotomies. Relieving the pressure normally allows the ulcer to heal. This procedure works very well in our experience. It’s important to use foot orthoses again after the surgery.”
According to PD Dr. Mehlhorn, claw toes themselves are also associated with a major wound risk. As he explains, diabetic patients with claw toes tend to develop an ulcer in one of two places: either up at the front at the tip or dorsally in the region of the proximal interphalangeal joints (PIP joints) of the toes. The specialist goes on to say that a great deal can be achieved in these cases through minimally invasive surgery. “Once the toe is straight again, the ulcer heals too. It’s essential to advise patients to use foot orthoses afterwards, both to preserve the result and to prevent new complications from arising,” the experienced physician explains.

Thinking about foot orthoses as soon as diabetes is diagnosed

The physician recommends that high-risk patients, i.e. diabetics with diagnosed neuropathy or peripheral arterial disease, should use complete foot cushioning that is specially adapted for patients with diabetes. “A custom-made shoe combined with an appropriate foot orthosis or else a diabetic-friendly shoe plus a foot orthosis is indicated for serious misalignments.” The orthopedic specialist stresses that while it is important that the foot orthosis is made by a skilled orthotist , it must also be checked over by the prescribing physician once it has been handed over: “Inspection and approval is mandatory!” There’s another point too which is very important to PD Dr. Mehlhorn: “In order to prevent complications, I would also like to see patients with diabetes wearing soft foam foot orthoses even if they don’t have any problems with their feet. It’s important to think about foot orthoses as soon as diabetes is diagnosed, because prevention is so important for patients with diabetes.” The specialist is keen to point out that he depends on help from others – not just family physicians, diabetes specialists, and orthopedic colleagues, but also members of the patient’s family: “Many people with diabetes try to avoid an appointment with the physician, because they find it difficult and are aware that it might be associated with bad news. It can sometimes be hard, therefore, for physicians to reach patients and to persuade them that foot orthoses, daily foot inspections, and other important prevention measures are essential.” He also explains that once people with diabetes are given a foot orthosis, they are often lulled into a false sense of security, wearing it well beyond the end of its serviceable life – which may cause problems. “The durability and shape retention of the foot orthosis is therefore very important. That’s why it’s all the more gratifying that manufacturers like Bauerfeind are tackling the issue of shape retention,” the specialist explains. “After all , sensitive diabetic feet need the best possible protection!”

Images: Conny Kurz