The soft, loose, and the childlike skew foot and the skewed flat-foot described below are by far the most common foot deformities.
This shape of the foot is characterized by a flattening of the longitudinal arch and an X-position (valgus) of the heel.
The foot bents inward when walking and is often associated with X-knees in children. The tibia rotates inwardly on the longitudinal axis when loaded and thereby the heel is pressed outwards. Since the hind foot is rigidly connected to the forefoot, the longitudinal arch flattens in this process. The causes of this deformity are of static and dynamic nature.
Causes are obesity, congenital connective tissue weakness, disturbances in bone metabolism, a faulty, turned-in position of the femoral head and the femoral neck, total misalignment of the leg axis (knock knees) and many other factors. Skew feet cause no other complaints except possibly an earlier fatigue and weakness.
Treatment is always conservative with inserts, therapeutic exercise, walking barefoot on uneven ground and frequent tiptoeing.
With these measures, and especially with a normal growth the most skew feet remain functional and asymptomatic in adolescence and adulthood. Occasionally some inward bent remains, but that does not cause much trouble. Patients should then later wear shoe inserts.
Left: The feet of an 8 year old girl. When standing the longitudinal arch bents inward and the heel goes into an X-position.
Right: When tiptoeing the arch straightens up and the heel is straight.