The Foot

The Foot

1. Bones

   • Tarsals
     • 7 irregular shaped bones
       • Proximal: talus & calcaneus
       • Intermediate: Navicular
       • Distal: Cuboid & 3 cuneiforms
   • Metatarsals
     • Located between the tarsals& phalanges
       • Numbered 1-5
         • They have 3 or 4 articulations
           • Proximally - Tarsometatarsal joint
           • Laterally - intermetatarsal joint
           • Distally - Metatarsophalangeal joint
   • Phalanges
     • Bones of toes
       • 3 phalanges : proximal, intermediate & distal
       • Great toe only has Prox' & Distal phalanges

2. Muscles

   • Extrinsic
     • Arise from the anterior and posterior & lateral compartments of the leg
       • Responsible for: eversion, inversion, plantar flexion & dorisfelxion
       • Extensor Digitorum Brevis
         • Lies deep to the tendon of extensor digitorum longus
           • It originates from the calcaneus, the interosseus talocalcaneal ligament and the inferior extensor retinaculum
           • It inserts into the long extensor tendons of the four medial digits.
         • Aids in extension of medial 4 toes
       • Extensor Hallucis Brevis
         • Medial to extensor digitorum longus
           • Originates from the calcaneus, the interosseus talocalcaneal ligament and the inferior extensor retinaculum
             • Inserts into base of proximal phalanx of the great toe
         • Extends the great toe
   • Intrinsic
     • Can be split into 4 layers (all 4 covered in another map)
       • 1st Layer
         • Abductor Hallucis Longus
           • Originates from medial tubercle of calcaneus, lexor retinaculum and the plantar aponeurosis
           • Inserts into medial base of prox' phalanx of great toe
           • Abducts and flexes great toe
         • Flexor Digitorum Brevis
           • Originates from medial tubercle of the calcaneus and the plantar aponeurosis
           • Inserts into middle phalanges of the lateral four digits.
           • Flexes lateral 4 digits
         • Abductor Digiti Minimi
           • Originates from medial & lateral tubercles of the calcaneus & the plantar aponeurosis
             • Inserts into base of the proximal phalanx of the 5th digit.
               • Abducts & flexes 5th digit

3. Ligament Support

   • Medial Ligament
     • Also known as the deltoid ligament
       • Consists of 4 separate ligaments
       • Which fan out from the malleolus, attaching to the talus, calcaneus and navicular bones.
     • Primary action of the medial ligament is to resist over-eversion of the foot.
   • Lateral Ligaments
     • Anterior Talofibuar
       • Spans between the lateral malleolus and lateral aspect of the talus.
     • Posterior Talfibular
       • Spans between the lateral malleolus and the posterior aspect of the talus.
     • Calcaneofibular
       • Spans between the lateral malleolus and the calcaneus.

4. Nerve Supply

   • 8 nerves innervate the foot
     • Tibial Nerve
     • Common Peraneal (deep & Superificial)
       • Medial Plantar
         • Lateral Plantar
       • Plantar Digital nerves
         • Calcaneal branches of tib & sural nerve
     • Sural
       • Saphenous

5. Vascular Supply

   • Blood comes from 3 primary sources
     • Peroneal (fibular) Artery
     • Prosterior Tibial Artery
     • Anterior Tibial Artery

Images and files in the map