In the clinical picture of splayfeet, the even load distribution on the foot is damaged. This results in overloading or incorrect loading, especially of the metatarsal head. If an inflammation develops in the joint between the tarsal and metatarsal bones (Articulatio tarsometatarsalis, Lisfranc joint) or in the metatarsophalangeal joints (Articulationes metatarsophalangeales), the stability of the foot is reduced.
This lack of stability favors the occurrence of splayfeet and fanning out to the sides. The inflammation often occurs in the context of rheumatoid arthritis. It is therefore not surprising that splayfeet and inflammatory rheumatoid arthritis are often associated with each other.
Particularly affected here are the contractile splayfeet, a special form in which the feet are completely stiffened. In addition to inflammation inside the joints of the feet, the permanent friction and pressure load causes small inflammations in the skin. Particularly in regions where the strain is particularly high, there is a local thickening of the cornea.
In this way, the body wants to protect the underlying, more sensitive skin layers from the inflammation that develops. The thickening of the cornea is called callus. Corneal calluses are very common in splayfeet and are found in the area of the ball of the foot, under the metatarsal heads.
Caution is required as soon as a corneal callus tears open. Germs can easily get into the bloodstream through the open skin! In the worst case, a purulent ulcer can develop under the sole of the foot and there is a risk of sepsis (‘blood poisoning’).
In advanced cases, corns (clavi) are found in splayfeet. At the point of greatest pressure, or most friction, the horny layer does not only grow to the surface, but with a deep, hard thorn into the layer below (subcutaneous tissue, subcutis). Under certain circumstances, germs can get into the foot and cause an inflammation.
There is also the risk of a fungal infection in the interdigital spaces between the toes (interdigital mycosis). Due to the foot malpositioning, toes can overlap (‘hammer toes‘) or rub against each other more strongly. This creates small niches in which athlete’s foot fungi can settle well. A good foot care, e.g. in the context of a podological treatment, is therefore a sensible preventive measure against external inflammation in case of splayfeet!
