Optimal Supination Requirements
- Calcaneus inverts beneath the talus and the talus dorsiflexes and externally rotates on top of the calcaneus – this motion occurs at the subtalar three joint complex.
- Navicular internally rotates relative to the talus and the cuboid – this motion occurs at the talonavicular joint and naviculocuboid joint (bifurcate ligament).
- Cuboid external rotates relative to the calcaneus and the navicular – this motion occurs at the calcaneocuboid joint and the naviculocuboid joint. Together the navicular and cuboid fold during this motion.
- Medial cuneiform internally rotates relative to the middle cuneiform and is drawn dorsal in space secondary to the plantarflexion of the metatarsals.
- Middle cuneiform remains neutral with respect to rotation and is drawn dorsal in space secondary to the plantarflexion of the metatarsals.
- Lateral cuneiform externally rotates relative to the middle cuneiform (axis of rotation for fanning and folding is around the 2nd ray) and is drawn dorsal in space secondary to the plantarflexion of the metatarsals.
- First MT adducts (to midline of foot) internally rotates and plantarflexes.
- 2nd MT remains neutral with respect to rotation and plantarflexes.
- 3rd, 4th and 5th MTs externally rotates and plantarflexes (5th MT adducts to midline of foot).
- Phalanges remains extended and MTP joints extend.
Optimal Pronation Requirements
- Calcaneus everts beneath the talus and the talus plantarflexes and internally rotates on top of the calcaneus – this motion occurs at the subtalar three joint complex – during gait the initial movement is an anterior slide of the talus as heel contacts ground and stops, because the axis of the anterior slide is anterior and medial the talar head contacts the middle facet and tips the calcaneus into eversion and talar head then falls medially (plantarflexes).
- Navicular externally rotates relative to the talus and the cuboid – this motion occurs at the talonavicular joint and naviculocuboid joint (bifurcate ligament).
- Cuboid internally rotates relative to the calcaneus and the navicular – this motion occurs at the calcaneocuboid joint and the naviculocuboid joint. Together the navicular and cuboid fan during this motion.
- Medial cuneiform externally rotates relative to the navicular and the middle cuneiform and is drawn plantar in space secondary to the dorsiflexion of the metatarsals
- Middle cuneiform remains neutral with respect to rotation and is drawn plantar in space secondary to the dorsiflexion of the metatarsals.
- Lateral cuneiform internally rotates relative to the middle cuneiform (axis of rotation for fanning and folding is around the 2nd ray) and is drawn plantar in space secondary to the dorsiflexion of the metatarsals.
- First MT externally rotates slightly relative to the medial cuneiform and the 2nd MT, abducts from the midline of the foot and dorsiflexes.
- 2nd MT remains neutral with respect to rotation and dorsiflexes.
- 3rd, 4th and 5th MTs internally rotates and dorsiflexes (5th MT abducts from midline of foot).
- Phalanges remains extended and MTP joints flex slightly.
