Flat foot


Flatfoot (Latin Pes planus) is a congenital or acquired foot deformity that occurs very frequently. In this case, the longitudinal arch of the foot (from the heel to the forefoot) sinks due to a weakness of the foot support system. This can cause the heel or forefoot to tilt to the outer edge.

In extreme cases, the foot can lie completely flat on the floor. The flat foot is a special form of flat foot. The longitudinal arch of the foot only lowers under load.
In contrast to a flat arch, which expresses itself in a similar footprint, the flat foot is permanently changed in its shape. He does not straighten up even in rest.

You might also be interested in: Buckle foot

Cause of flat foot

The cause of the development of a flat foot are incorrect development of the foot skeleton. The healthy foot is arched lengthways on the inner edge. This means that the foot is usually about a finger's breadth off the ground. The defective foot skeleton in flat feet leads to the lowering of this longitudinal arch and a raised heel.

Depending on the shape of the flat foot, acquired or congenital, the causes of the foot deformity differ. The congenital flat foot (congenital flat foot) is rather rare and usually occurs in combination with other congenital malformations. This form of flat foot often appears in families. This suggests that flat feet can be passed on for generations.

The acquired flat foot, on the other hand, is mainly caused by insufficient function of muscles and ligaments.
Reasons for the lack of function can be permanent overload, constant standing, overweight, weak connective tissue or a previous broken heel. But other diseases such as polio, rickets, neurological or rheumatic diseases can lead to foot deformities. These affect the tendons and muscles of the arch of the foot, which means that it is no longer supported efficiently and it sinks.
Constant wearing of shoes can also cause flat feet. Since shoes restrict the freedom of movement of the feet and toes and also protect the feet from minor stimuli, the foot muscles are not trained sufficiently and are not strong enough.

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My name is dr. Nicolas Gumpert. I am a specialist in orthopedics and the founder of .
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Athletes (joggers, soccer players, etc.) are particularly often affected by diseases of the foot. In some cases, the cause of the foot discomfort cannot be identified at first.
Therefore, the treatment of the foot (e.g. Achilles tendonitis, heel spurs, etc.) requires a lot of experience.
I focus on a wide variety of foot diseases.
The aim of every treatment is treatment without surgery with a complete recovery of performance.

Which therapy achieves the best results in the long term can only be determined after looking at all of the information (Examination, X-ray, ultrasound, MRI, etc.) be assessed.

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Further information about myself can be found at Dr. Nicolas Gumpert


Complaints on the inner edge of the foot, around the navicular bone and in the area of ​​the sole of the foot are particularly common.

In some cases, pain in the calves, knees, thighs and back (see also back pain) is complained. The reason for this is the changed load on the entire foot and the unevenly distributed force. If the flat foot is very pronounced, there is usually no more pain.

Read more about the topic here: Tibialis posterior syndrome


Flatfoot can be recognized by simply looking at the foot, especially in the case of severe malpositions. The foot rests much further on the ground than the healthy foot. In some cases, the sole of the foot lies flat on the ground. This seems rounded outwards (convex) and the tarsal bones are rounded towards the sole of the foot.
The Achilles tendon is usually shortened and the forefoot appears splayed and pulled upwards (dorsally extended). The congenital flat foot shows in the X-ray a steeply positioned talus ("Talus verticalis“).


In order to choose the right therapy for flatfoot, flatfoot can be divided into different stages.

In stage 1 the doctor can passively correct the misalignment and the patient can also actively straighten the longitudinal arch. The Achilles tendon is not yet shortened here.

Also in stage 2 the foot can still be moved passively into the correct position, but the Achilles tendon is already slightly shortened.

In stage 3 the foot position can only be partially corrected passively, the Achilles tendon is significantly shortened and the rear part of the foot points outwards.

Severity 4 corresponds in its picture to the signs of severity 3.However, in addition to the shortening of the Achilles tendon and the displacement of the rear part of the foot, there is also a splaying of the front foot.

In severity 5 the misalignment can no longer be corrected. In addition, the heel is (Rear foot) high and the head of the talus protrudes from the inner edge of the foot. In addition, the forefoot is constantly spread apart. This leads to the rise of the inside and the lowering of the outer edge of the foot.

Treat flat feet with insoles

The adult foot can beside active exercises can only be treated with insoles, since the growth and thus a bony correction is complete.

Read everything about this under our topic: Insoles for flat feet

Flat foot on the Nile

And the most famous form of flat foot is the "flat foot on the Nile" with Bud Spencer and Terrence Hill.
And since we have the right to fully inform about the subject of "feet", we have an article on "Flatfoot on the Nile".

Correct flat feet

Flat feet can only be corrected causally through insoles, exercises and physiotherapy while they are growing.
Once the growth is complete, you can still try to hold the situation and achieve freedom from pain. Finally, there is the option of surgery.

Read everything about our topic: Correct flat foot