Foot = pliable + rigid

• P: shock and conform to the pattern of the ground
• R: And to provide a rigid lever to transfer propulsive forces for movement

Osteology: basic terms

Osteology: fibula

Osteology: distal tibia

Osteology: talus

Osteology: talus (lateral side+eagle view)

Osteology: calcaneus

Osteology: navicular

Osteology: cuneiforms

Osteology: cuboid

Osteology: metatarsals

“ray” = one metatarsal and its associated set of phalanges

Osteology: phalanges

Arthrology: terminology first

Arthrology: proximal tibiofibular

Arthrology: distal tibiofibular

Arthrology: talocrural joint, articular structure

Arthrology: talocrural joint, ligaments

Movement of stretch and elongate major ligaments

• deltoid ligaments
  • tibiotalar
  • tibionvicular
  • tibiocalcaneal
• calcaneaofibular ligament
• posterior talofibular ligament

Osteokinematics: talocrural

• Posterior
  • AB/ADduction (vertical axis)
  • Dorsiflexion/Plantar flexion (Med.Lateral axis)
• Superior
  • EV/INversion (Ant.Posterior axis)
  • Dorsiflexion/Plantar flexion (Med.Lateral axis)

Arthrokinematics: talocrural joint

Arthrokinematics: talocrural joint

The. Subtalar. Joint

Subtalar articular structure & ligaments

• calcaneofibular
• tibiocalcaneal fibers of deltoid ligament
• interosseous (talocaneal) cervical

Subtalar kinematics

Transverse tarsal joint (midtarsal)

Midtarsal: talonavicular joint

Midtarsal: calcaneocuboid

Midtarsal kinematics

• pronation
• supnation

Midtarsal kinematics (transverse tarsal joint longitudinal axis)

Midtarsal kinematics (transverse tarsal joint oblique axis)

Midtarsal arthrokinematics

• Consider it in the unloaded state
• The navicular spins on the talus
  
  • Supination: inverts the lateral column “under” the medial
  • Pronation: everts the medial column “under” the lateral

Medial longitudinal arch

Medial longitudinal arch: passive restraints

Combined actions of subtalar & midtarsal joints

COMBO MNT // STJ- closed kinematic chain motions // INTERNAL ROTATION

• RearFT + MidFT (supination) + rearFT (pronation)
• lower arch = rearfoot eversion

COMBO MNT // STJ- closed kinematic chain motions // rearfoot supination + inversion // EXTERNAL ROTATION

• supination: lock in place
  
  • behave separately (force vs. rearfoot)
  • more ridged
• ForeFT + MidFT (pronation) + RearFT (supination) = IN + OUT
  • raise arch = rearfoot inversion
• closed chain
  
  • weight bearing on foot

Distal intertarsal joints (x3)

1. Cuneonavicular joint
2. Cuboidnavicular joint
3. Intercuneiform & cuneocuboid

Distal intertarsal joints: Cuneonavicular joint

Main job is to transfer pronation & supination distally toward the
forefoot

Distal intertarsal joints: Cuboidnavicular joint

nothing significant

Distal intertarsal joints: Intercuneiform & cuneocuboid

• Form the transverse arch of the foot
  • provides transverse stability to the midfoot

Tarsometatarsal joints

• plantar flexion // eversion
• dorsiflexion // inversion

Phalanges + tarsi

Intermetatarsal joints

• Not a real joint
• Held together loosely with muscles, ligaments  allows flexibility

Metatarsophalangeal joints

Action of the forefoot; the Windlass mechanism

• foot rolls backwards
• turn on calf (extrinsic muscle) = raise arch (intrinsic muscles)
  • bridge mvt with bungee cord

Dorsiflexion inversion muscles

1. extensor hallucis longus
2. tibialis anterior

Dorsiflexion eversion muscles

1. extensor digitorum longus
2. fibularis tertius

plantar flexion inversion muscles

1. tibialis posterior
2. flexor digitorum longus
3. flexor hallucis longus
4. achilles tendon

plantar flexion eversion muscles

1. fibularis brevis
2. fibularis longus

Muscle action

• foot mvt along the lateral axis (lateral + vertical)
  • talocrural joint axis(lateral) + subtalar joint (vertical)
• Dorsiflexion inversion // Dorsiflexion eversion
• plantar flexion inversion // plantar flexion eversion

Muscle function: extrinsic muscles, anterior compartment

• eversion, inversion, plantarflexion and dorsiflexion of the foot

1. extensor hallucis longus muscle
2. tibialis anterior,
3. extensor digitorum longus
4. fibularis tertius muscles.

Muscle function: extrinsic muscles, lateral compartment

EVERSION

1. fibularis longus
2. fibularis brevis

Muscle function: extrinsic muscles, posterior compartment (x6)

• superficial (x3)
• deep (x3)

Muscle function: extrinsic muscles, posterior compartment // SUPERFICIAL

• Gastrocnemius
• Soleus
• Plantaris

Muscle function: extrinsic muscles, posterior compartment // DEEP

• Tibialis posterior
• Flexor digitorum longus
• Flexor hallucis longus

Muscle function: extrinsic muscles, posterior compartment (GRAPH + LIG)

• Isometric torque (HIGH to LOW)
  • plantar flexion
  • dorsiflexion
  • inversion
  • eversion

Muscular Function: Intrinsic Muscles

• maintain the medial longitudinal arch
• aid in force distribution
• postural control during gait

what is roll slide on tibial on talor

concave on convex (SAME)

what does the "mortise + tendon" joint consist of?

• fibula
• tibia
• talus

what does the shape of the talus mean for ankle stability?

• wedge shape = UP compressive force + UP stability of TC joint in DF

3 parts of the foot?

• front foot
• mid-foot
• rear foot