Anatomy 33 Flashcards
What does the expanded proximal end of the tibia articulate with?
The femur to form the knee joint
What does the distal end of the tibia articulate with?
The talus and fibula
What does the proximal part of the tibia form?
Forms medial and lateral tibial condyles
What are the superior surface of the condyles called?
Medial and lateral tibial plateaus
What do the medial and lateral tibial plateaus articulate with?
Femoral condyles to form the knee joint
What lies between the tibial plateaus?
Intercondylar tubercles
Where does the tibial tuberosity project from?
The upper anterior surface of the tibia and is palpable
What lies in the tibial tuberosity?
Patellar ligament
What is the soleal line?
An oblique ridge of bone on the posterior surface of the tibia
Where does the medial malleolus project?
Medially from the distal end of the bone and forms part of the ‘socket’ for the talus
What does the proximal part of the fibula form?
Forms the head, which is palpable
What structure lies close to the neck of the fibula?
Common peroneal (fibula) nerve
Where does the lateral malleolus project?
From the distal end of the bone and forms part of the ‘socket’ for the talus
What is the human foot adapted for?
Bipedal gait
What do the small joints of the foot allow?
Allow the foot to deform and absorb shock when walking over uneven ground
What are the longitudinal and transverse arches of the foot formed by?
Arrangement of the bones of the foot
What is the function of the longitudinal and transverse arches of the foot?
Allows shock absorption
What are the longitudinal and transverse arches of the foot supported by?
Ligaments and tendons in the foot
What do the tarsal bones comprise of?
Talus
Calcaneus (heel bone)
Navicular
Cuboid
3 cuneiforms (medial, intermediate and lateral)
What does the talus articulate with?
Tibia and fibula at the ankle joint
What bones are referred to as the hindfoot?
Talus and calcaneus
What bones comprise of the midfoot?
Navicular
Cuboid
Cuneiforms
What bones comprise of the forefoot?
Metatarsals
Phalanges
From which side are the metatarsals numbered 1-5?
Medial (big toe) side to the lateral (little toe) side
How many phalanges in toes 2-5?
3
How many phalanges in the big toe?
2
What are the 3 phalanges named?
Proximal, middle and distal
What are the 2 phalanges named?
Proximal and distal
Where do the metatarsophalangeal joints (MTPJ) lie?
Lie between the metatarsals and the proximal phalanges
Where do the Interphalangeal joints (IPJ) lie?
Lie between the phalanges
What joint lies between the 2 phalanges of the big toe?
nterphalangeal joint of the big toe (IPJ)
What joint lies between the 2 phalanges of the big toe?
Interphalangeal joint of the big toe (IPJ)
What joints are found between the 3 phalanges of toes 2-5?
● the proximal interphalangeal joint lies between the proximal and middle phalanx (PIPJ)
● the distal interphalangeal joint lies between the middle and distal phalanx (DIPJ)
What movements can the foot execute?
● Dorsiflexion (extension) - at the ankle joint
● Plantarflexion - at the ankle joint
● Inversion - at the subtalar joint.
Inversion brings the sole of the foot medially.
● Eversion - at the subtalar joint.
Eversion brings the lateral border and sole of the foot laterally
What is the subtalar joint formed by?
Articulation of the talus with the calcaneum and navicular
What movements can the toes execute?
● Flexion
● Extension
● Abduction (moving the toes apart)
● Adduction (bringing the toes together)
What separates the leg into anterior, lateral and posterior compartments?
Intermuscular septa that extends from the deep fascia
What 3 muscles are found in the anterior compartment of the leg?
● Tibialis anterior
● Extensor hallucis longus (EHL)
● Extensor digitorum longus (EDL)
Where do the 3 muscles in the anterior compartment of the leg arise from?
Tibia, fibula and interosseous membrane
What do the 3 muscles in the anterior compartment of the leg primarily act as?
Dorsiflexors (extensors) of the foot at the ankle joint and extensors of the toes
What are the 3 muscles in the anterior compartment of the leg innervated by?
Deep peroneal nerve
What does the tibialis anterior insert onto?
Crosses the anterior aspect of the ankle and inserts onto the medial cuneiform
What movements does the tibialis anterior execute?
Dorsiflexes and inverts the foot
What does the extensor hallucis longus insert onto?
Its tendon crosses the anterior aspect of the ankle and inserts onto the distal phalanx of the big toe
What movements does the extensor hallucis longus execute?
Extends the big toe
Dorsiflexes the foot at the ankle
How many tendons does the extensor digitorum longus give rise to?
4
What do the tendons of the extensor digitorum longus insert onto?
Cross the anterior aspect of the ankle and insert onto the distal phalanges of toes 2-5
What movements does the extensor digitorum longus execute?
Extends the digits
Dorsiflexes the foot at the ankle joint
What does the extensor retinacula overlie?
The extensor tendons at the ankle joint
What do the muscles of the lateral compartment of the leg attach to?
Fibula
What movement do the muscles in the lateral compartment of the leg execute?
Evert the foot at the subtalar joint
What are the muscles in the lateral compartment of the leg innervated by?
Superficial peroneal nerve
What muscles are found in the lateral compartment of the leg?
● Peroneus longus (fibularis longus)
● Peroneus brevis (fibularis brevis)
Which muscle in the lateral compartment of the leg is more superficial?
Peroneus longus
What does the peroneus longus insert onto?
Plantar surface of the medial cuneiform bone
What does the peroneus brevis insert onto?
The base of the 5th metatarsal
Where do the tendons of the peroneus longus and brevis travel?
Posterior the lateral malleolus to their insertions in the foot
What does the popliteal artery bifurcate into?
Anterior and posterior tibial arteries in the popliteal fossa
What path does the anterior tibial artery take?
Pierces the interosseous membrane to enter the anterior compartment of the leg, which it supplies.
It crosses the anterior aspect of the ankle joint and enters the dorsum of the foot.
Here, the artery is called the dorsalis pedis artery, and is palpable in the foot lateral to the tendon of extensor hallucis longus.
Where does the anterior tibial artery become the dorsalis pedis artery?
Dorsum of the foot
What does the dorsalis pedis artery give rise to?
Branches that travel between the metatarsals and anastomose with arteries in the plantar aspect of the foot
What is the lateral compartment of the leg supplied by?
Fibular artery
What is the fibular artery a branch of?
Posterior tibial artery
What are the 2 major superficial veins in the leg which drain the foot?
Great saphenous vein
Small saphenous vein
Where does the great saphenous vein travel?
Anterior to the medial malleolus and courses all
the way up the medial aspect of the lower limb to its termination at the femoral vein in the femoral triangle
Where does the small saphenous vein travel?
Travels posterior to the lateral malleolus and courses up
the posterior aspect of the leg to its termination at the popliteal vein in the popliteal fossa
What does the common peroneal nerve divide into?
Superficial and deep peroneal nerves
What does the superficial peroneal nerve innervate?
Muscles of the lateral leg
What does the deep peroneal nerve innervate?
Muscles of the anterior leg
What do both branches of the common peroneal nerve innervate?
Regions of skin of the leg
What small muscle is found in the dorsum of the foot?
Extensor digitorum brevis
Where does the extensor digitorum brevis lie?
Laterally
What does the extensor digitorum brevis give rise to?
4 slender tendons that insert into toes 2–5
What is the extensor digitorum brevis innervated by?
Deep peroneal nerve
Describe what may happen during a tibial fracture
High energy forces are required to fracture a healthy tibia.
When the tibia fractures, the broken ends of the bone may break through the skin because there is little
subcutaneous tissue between the anterior surface of the tibia and skin.
Open fractures must be managed carefully to prevent infection from entering the exposed bone
What is bone infection called?
Osteomyelitis
Describe what may happen in common peroneal nerve injury
The common peroneal nerve lies relatively superficially as it wraps around the neck of the fibula.
Fractures of the fibular neck, caused by a lateral blow to the leg, can injure the nerve.
This leads to weakness of the anterior and lateral leg muscles.
The foot cannot be dorsiflexed and the toes will drag on the ground when walking. This condition is called foot drop.
Patients compensate either by lifting the leg (by flexing
the hip and knee to a greater degree) or by swinging the affected leg out – both allow the toes to clear the ground
Where is the pulsation of the dorsalis pedis artery usually easily palpable?
Over the dorsum of the foot, just lateral to the tendon of extensor hallucis longus, between the first and second metatarsal
Where is the pulse of the posterior tibial artery palpable?
Posterior to the medial malleolus.
Because it travels behind the medial malleolus with other structures, it can be tricky to palpate.
