Flat feet (lat. pĭatrum - sole, lat. pēdis - leg), or fissure flat feet (Greek μπλᾰχία) - transverse flat feet with flattening of the longitudinal arch of the foot by more than 25 mm.
- Flat feet appear as a result of foot injuries; without external deformations, the foot is flattened in the transverse direction. This type of flatfoot is different in that a person can suffer from it since childhood and not notice it. Such forms of flat feet are manifested by severe pain when standing for a long time, rapid fatigue of the feet, especially when performing work.