Ch.6 - Toes, Feet, Ankle, and Calcaneus

• There are 26 bones in a foot:

  • 14 Phalanges
  • 5 Metatarsals
  • 7 Tarsals
• The base of the 5th metatarsal is fractured the most often on a foot
• The 7 foot tarsals:

  • Calcaneus
  • Talus
  • Cuboid
  • Navicular
  • 3 Cuneiforms (Medial, Intermediate, and Lateral)
• Mneumonic for the tarsals:

  • Come
  • To
  • Colorado
  • Next
  • 3 Christmases
• The calcaneus is the strongest, largest, and most posterior bone of the foot
• The calcaneus has the sustentaculum tali, which is located medially and supports the talus
• The calcaneus' tuberosity is the most posterior-inferior part of it and is an attachment site for the Achilles tendon; it's a common site for bone spurs
• Sinus Tarsi: An opening in the subtalar joint of the foot formed by the calcaneal sulcus and talus that contains the posterior tibial nerve
• An internal oblique position of the foot will open up the sinus tarsi
• The 3 facets of the talus: Are surfaces for other bones to articulate to

  • Posterior
  • Middle
  • Anterior
• The talus is the most superior bone in the foot
• Arches of the foot: Provide strong shock absorbing support for body weight

  • Longitudinal Arch
  • Transverse Arch
• Surfaces of the foot:

  • Dorsal (Anterior)
  • Plantar (Posterior)
• Ankle movements:

  • Inversion (Varus): Ankle bowed inward
  • Eversion (Valgus): Ankle bowed externally
• The ankle joint is formed by the tibia, fibula, and talus
• The mortise joint: A 3 sided opening formed by the medial and lateral malleolus; in which the talus fits
• Tibial plafond (ceiling): Forms the roof of the mortise joint
• The lateral malleolus hangs lower than the medial malleolus
• On a true lateral ankle, the distal fibula is over the posterior half of tibia
• kVp Ranges:

  • Toes/Feet: 60 +- 5
  • Ankle: 65 +- 5
  • Calcaneus: 70 +- 5
• AP Toes:

  • CR: 10 to 15 degrees posterior to 3rd MTP joint
  • kVp: 60 +- 5
  • SID: 40” and 8x10 CW