[Acquired flat foot of the adult by posterior tibial dysfunction. Options for surgical treatment].

We present the possible etiopatogenic causes of posterior tibial dysfunction or painful flat foot of the adult and the cause-and-effect relationship that may exist. We also expose the gradation of the lesion and the different therapeutic options for the surgical treatment of the deformity. Since 1939, multiple articles have been published, which have been endorsed by clinical, experimental, electromyographic and biomechanical studies; publications that have been consulted and evaluated for the development of this review. In our opinion: the dysfunction of the posterior tibial is caused in principle by a failure of the plantar navicular calcaneus ligament (spring ligament), the main passive stabilizer of the internal plantar arch. This failure would, in time, mean an increase in work of the posterior tibial tendon, in itself "insufficient", which would go into fatigue, until it reached a partial or total rupture. Published work on soft-part procedures acting on the posterior tibial tendon in stage II has not had the expected result in the natural history of deformity. Arthrodesis, on the other hand, has been effective in other stages, but is associated with a loss of movement dynamics in the back foot and increased pressure on adjacent joints.