L11

Sole of Foot

• The sole of the foot is a thick layer of skin that offers protection.
• It firmly adheres to the plantar aponeurosis.
• The skin has creases.
• The plantar aponeurosis is a thickened band of deep fascia.
• Posteriorly, it's attached to the calcaneum.
• Anteriorly, it has five slips that connect to the five toes.
• It protects underlying nerves and vessels.
• It maintains the longitudinal arches of the foot.

First Layer Muscles

• Abductor hallucis: Innervated by the medial plantar nerve; action is abduction of the great toe.
• Flexor digitorum brevis: Innervated by the medial plantar nerve; action is flexion of the lateral four toes.
• Abductor digiti minimi: Innervated by the lateral plantar nerve; action is abduction of the little toe.

Second Layer Muscles and Tendons

• Flexor hallucis longus (FHL): A tendon.
• Flexor digitorum longus (FDL): Atendon.
• Quadratus plantae: A muscle.
• Four lumbricals: Muscles.
• The quadratus plantae assists in plantar flexion, and is innervated by the lateral plantar nerve.

Second Layer Lumbricals

• Origin: Tendons of the FDL muscle.
• Insertion: Middle and distal phalanges of the lateral four toes.
• Nerve Supply: 1st - medial plantar nerve; 2nd, 3rd, and 4th - lateral plantar nerve.
• Action: Flexion at the MCP and extension at the IP joints.

Third Layer Muscles

• Flexor hallucis brevis: Medial plantar nerve.
• Adductor hallucis: Lateral plantar nerve.
• Flexor digiti minimi brevis: Lateral plantar nerve.

Fourth Layer Muscles and Tendons

• Two tendons: Tibialis posterior and Peroneous longus (fibularis longus).
• Three plantar interossei muscles: Innervated by lateral plantar nerve; action: adduction of the 3rd, 4th, and 5th toes to the long axis passing through the second toe.
• Four dorsal interossei muscles: Innervated by the lateral plantar nerve; action: abduction of the second to fourth toes at the metatarsophalangeal joint.

Arteries of the Sole

• Medial plantar artery: A smaller terminal branch of the posterior tibial artery; enters the sole with the medial plantar nerve. Muscular and digital branches.
• Lateral plantar artery: A larger terminal branch of the posterior tibial artery; enters the sole with the lateral plantar nerve. Muscular branches and the 5th plantar metatarsal artery.

Plantar Arch

• The plantar arch runs from the fifth metatarsal to the first metatarsal.
• Formed by the continuation of the lateral plantar artery and anastomoses between the deep branch of the dorsalis pedis artery.
• Gives plantar metatarsal arteries.
• Veins accompany the arteries of the sole. Medial and lateral plantar veins.

Plantar Fasciitis

• Inflammation of the plantar fascia.
• A common cause of heel pain.
• Stabbing pain, common in the morning, eventually reduced throughout the day.
• Long periods of standing intensify the pain.
• Common in runners or professions involving prolonged standing (teachers, ballet dancers).
• Obesity and stress on the fascia can contribute to inflammation.

Ankle Joint

Objectives

• Classify the ankle joint.
• Name the articulating bones in the ankle joint.
• Identify the ligaments of the ankle joint.
• Name the movements of the ankle joint.
• Name the muscles that bring about the movements.

Articulating Bones

• Inferior surface of the tibia.
• Medial malleolus.
• Lateral malleolus.
• Superior surface of the talus.
• Hinge variety of synovial joint.

Ligaments

• Medial (deltoid): Ligament.
• Laterally:
  • Anterior talofibular ligament.
  • Posterior talofibular ligament.
  • Calcaneofibular ligament.

Deltoid Ligament Parts

• Tibio-talar part.
• Tibio-calcaneal part.
• Tibio-navicular part.

Movements

• Dorsiflexion: Tibialis anterior, gastrocnemius, soleus.
• Plantarflexion:
• Inversion:
• Eversion:

Talocalcaneal/Subtalar Joint

• Plane synovial joint.

Joints of the Foot

• The ankle joint (tibia, fibula, and talus).
• The subtalar joint.
• The transverse tarsal joint.