Dynamic orthosis made of flexible thermoplastic, available in two heights, comprising an internal, low density thermoplastic (LDPE) part that covers the back of the leg, which stays in contact with the entire plantar surface. It encloses the entire perimeter of the midfoot, ensuring that the orthosis fits the foot correctly, while optimising containment of the tissues.A more rigid external part made of thermoplastic (PP) provides firm support to control the biomechanical positioning and alignment of the limb. It reaches the proximal edge of the metatarsal heads. The fastening system and Velco closure system allows a comfortable and firm adaptation and an adequate fit while preventing movement between the foot and the orthosis. Very lightweight and with a trimmable hem, its low profile design is easy to adjust in the shoe. To ensure greater comfort, pads for the toes and the dorsal midfoot are included.