| Medial Arch Support |
- In order of importance
- capsuloligamentous (especially plantar) structures
- plantar fascia (Windlass mechanism)
- dynamic support of tibialis posterior muscle
- joint congruity and alignment
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| Plantar aponeurosis (Windlass mechanism) |
- Function
- increase arch height as toes dorsiflex during toe-off
- major (2nd most important) medial arch support
- Origin
- medial-plantar aspect of calcaneal tuberosity
- Insertion
- toes 1-5 flexor tendon sheath near base of proximal phalanx
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| Plantar plate of 2nd MTP joint |
- Must become lax before abnormal dorsal translation of proximal phalanx can occur
- once attenuated, most deforming force is EDL
- Weakest at origin of metatarsal neck
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| Transverse metatarsal ligament |
- Function
- holds hallucal sesamoids in place as 1st MT head moves medially
- can lead to false image of sesmoid subluxation
- head is moving, not the sesmoids
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