Anatomy of the leg and foot Flashcards
Function of the foot
Support body weight
Stability/ standing
Locomotion/ propulsion (lever)
Shock asborption
Bones of the leg
Fibula
Tibia
- lateral malleolus
- medial malleolus
Bones of the foot
Tarsal
Metatarsals
Phalanges
Sesamoid bones
Tarsal bones
Calcaneous
Talus
Cuboid
Navicular
Cuneiforms
Movement of the foot
Dorsiflexion/ extension
Plantarflexion/ flexion
Eversion
Inversion
Supination
Joints of the foot
Ankle joint
- dorsiflexion/ plantarflexion
Intertarsal joints
- invert/ evert
- supinate/ pronate
Metatarsophalangeal joints
- extension/ flexion
- limited abduction/ adduction
Interphalangeal joints
- extension/ flexion
Ankle
Articulation between the thalus and tibia/ fibula
Synovial hinge joint
Ankle
Stabilised by collateral ligaments
Lateral ligament- lateral malleolus to talus/ calcaneous
Medial/ deltoid ligament- medial malleolus to talus/ calcaneous/ navicular
Clinical: ankle
Injury to lateral ligament (usually anterior talofibular ligament)
Subtalar joint
Between talus and calcaneous (and navicular)
Allows inversion/ eversion during locomotion
Transverse tarsal joint
Between forefoot and hindfoot
Allows pronation/ supination (eversion/ inversion of forefoot)
Important for standing on uneven ground
Plantar aponeurosis
Thickening of deep fascia
Protects underlying structures
Supports longitudinal arch
Clinical: plantar aponeurosis
Plantar fasciitis (inflammation due to overuse)
Arches of the foot
Longitudinal and transverse arches
Function
- shock absorbers during locomotion
- act as springboards
- distribution of weight (to calcaneous and ball of foot)
Longitudinal arches
Lateral and medial arches
Supported by long tendons, intrinsic plantar muscles, intrinsic ligaments and plantar aponeurosis
Clinical: longitudinal arches
Fallen medial longitudinal arch can lead to pes planus (flat feet)
Transverse arch
Supported by long tendons
Muscle compartments
Anterior
- extend/ invert foot
Posterior
- flex/ invert foot
Lateral
- evert foot
Anterior compartment of leg
Three muscles
Extend and invert foot
Origin: tibia and fibula
Supplied by deep fibular nerve
Tibialis anterior
- extends/ inverts foot
Extensor digitorum longus
- extends lateral 4 toes
Extensor hallucis longus
- extends great toe
Extensor digitorum longus
Middle and distal phalanges
Tibialis anterior
Medial cuneiform and 1st metatarsal
Extensor hallucis longus
Distal phalanx of great toe
Posterior compartment of leg- superficial group
Flex foot and leg
Supplied by tibial nerve
Plantaris
Soleus
Gastrocnemius
Tendo calcaneous
Posterior compartment of leg- deep group
Flex and invert foot and flex toes
Origin: tibia and fibula
Supplied by tibial nerve
Flexor digitorum longus
Tibialis posterior
Flexor hallucis longus
Flexor digitorum longus
Distal phalanges
Flexor hallucis longus
Distal phalanx of great toe
Tibialis posterior
Medial cuneiform and navicular
Lateral compartment of leg
Evert foot
Supplied by superficial fibular nerve
Fibularis longus
- everts and plantar flexes foot
Fibularis brevis
Lateral long tendons of the foot
Extensor retinaculum
Fibular retinaculum
Extensor digitorum longus
Extensor hallucis longus
Fibularis longus/ brevis
Medial long tendons of the foot
Flexor retinaculum
Tibialis anterior
Tibialis posterior
Flexor digitorum longus
Flexor hallucis longus
Intrinsic muscles of the foot
Many layers
- dorsal extensors- 1 layer
- plantar flexors/ abductors/ adductors- 4 layers
Blood supply
Posterior compartment
- popliteal artery
- anterior tibial artery
- posterior tibial artery
- fibular artery
Tarsal tunnel
Contents
- tibialis posterior
- flexor digitorum longus
- posterior tibial artery/ vein
- tibial nerve
- flexor hallucis longus
Clinical: tarsal tunnel
Pulse and tarsal tunnel syndrome
Blood supply: anterior compartment
Anterior tibial artery
Dorsalis pedis
- sites behind the extensor hallucis longus tendon
Anastomosis with deep plantar arch
Clinical: dorsalis pedis artery
Pulse
Nerve supply to the leg
Supplied by the terminal branches of the sciatic nerve
Tibial- posterior compartment
Deep fibular- anterior compartment
Superficial fibular- lateral compartment
Clinical: tibial nerve
Tarsal tunnel syndrome
Tibial nerve
Motor: posterior compartment of leg and plantar intrinsic muscles
Common fibular nerve
Motor
- deep: anterior compartment of leg and dorsal intrinsic muscles
- superficial: lateral compartment of leg
Clinical: common fibular nerve
Trauma to common fibular nerve (foot drop)
Cutaneous nerves
Common fibular nerve
Superficial fibular nerve
Deep fibular nerve
Saphenous nerve (femoral nerve)
Sural nerve (tibial nerve)
Medial/ lateral plantar nerves (tibial) supply sole of foot
