Lower limb Flashcards
What are the nerve roots of the sural nerve?
S1,2
Where does the sural nerve come from?
Medial sural cutaneous nerve (from tibial nerve) and lateral sural cutaneous nerve (from common fibular nerve)
What areas of skin does the sural nerve supply?
Posterolateral aspect of the distal third of the leg, ankle, foot and heel
What is the pathway of the sural nerve?
It runs alongside the small saphenous vein, it descends between the two heads of gastrocnemius
Which vein does the small saphenous vein drain into?
The popliteal vein
What is the pathway of the small saphenous vein?
It comes from the foot posterior to the lateral malleolus, then ascends along the posterior surface of the leg between the heads of gastrocnemius
What are the attachments of gastrocnemius?
O: Lateral head: posterolateral aspect of lateral condyle of femur. Medial head: posterior surface of medial femoral condyle, posterior femoral shaft
I: posterior surface of calcaneus via calcaneal tendon
What is the innervation to gastrocnemius?
Tibial nerve (S1,2)
What is the function of gastrocnemius?
Knee joint: leg flexion
Talocrural joint: foot plantar flexion. Explosive movements
What are the attachments of soleus?
O: Soleal line, medial border of tibia, head and posterior border of fibula
I: Posterior surface of calcaneus via calcaneal tendon
What is the innervation to soleus?
Tibial nerve (S1,2)
What is the function of soleus?
Talocrural joint: Foot plantar flexion
What artery supplies the posterior compartment of the leg?
Posterior tibial artery
Which muscles does the common fibular nerve supply?
Anterior leg muscles (tibialis anterior, extensor hallucis longus, extensor digitorum longus). lateral leg muscles (fibularis longus, fibularis brevis) Dorsal foot muscles (extensor digitorum brevis, extensor hallucis brevis)
Which areas of skin are supplied by the common fibular nerve?
Anterolateral leg, dorsum of foot, skin of webspace between great and 2nd toe
What are the nerve roots of the common fibular nerve?
L4-S2
What are the two main divisions of the common fibular nerve?
Deep - supplying muscles
Superficial - supplying skin
What is the pathway of the tibial nerve?
Descends from popliteal fossa into posterior compartment of the leg, deep to soleus, passes behind the medial malleolus to enter the sole of the foot
What are the nerve roots of the tibial nerve?
L4-S3
Which muscles does the tibial nerve supply?
Posterior compartment of the leg, intrinsic muscles on the sole of the foot
Which areas of skin does the tibial nerve supply?
Skin of the posterolateral leg (sural nerve), lateral foot, sole of foot
What are the attachments of plantaris?
O: Lateral supracondylar line of femur
I: Posterior surface of calcaneus via calcaneal tendon
What is the innervation to plantaris?
Tibial nerve (S1,2)
What are the actions of plantaris?
Foot plantar flexion and knee flexion
What are the attachments of popliteus?
O: Lateral condyle of femur
I: Posterior surface of proximal tibia
What is the innervation to popliteus?
Tibial nerve (L4-S1)
What is the function of popliteus?
Unlocks the knee
Which artery does the dorsalis pedis artery come from?
The anterior tibial artery
What is the pathway of the anterior tibial artery?
it comes off the popliteal artery posterior and inferior to the knee, passes through the oval aperture in the interosseous membrane into the anterior compartment, descends down the leg in front of the medial malleolus
What does the anterior tibial artery supply?
Anterior compartment of the leg, knee, ankle joint
What does the posterior tibial artery supply?
The posterior compartment of the leg and sole of the foot
What is the pathway of the posterior tibial artery?
From popliteal artery, descends through posterior compartment of the leg, enters foot by passing inferiorly to the medial malleolus
Where does the fibular artery arise from?
The posterior tibial artery
What does the fibular artery supply?
Lateral and some of the posterior compartment of the leg
What are the borders of the popliteal fossa?
Superomedial: semimem+tend Lateral: biceps femoris Inferior: gastrocnemius Floor: knee joint, popliteus Roof: popliteal fascia
What are the contents of the popliteal fossa?
Nerves: tibial, common fibula, sural, posterior femoral cutaneous
Vessels: popliteal artery, vein, short saphenous vein
What is the mnemonic to remember the order of contents of the popliteal fossa?
Serve And Volley Next Ball - Semimem/tend, Artery, Vein, Nerve, Biceps femoris
What are the attachments of the plantar aponeurosis?
Medial tubercle of calcaneus
head of all 5 metatarsal bones, skin of toes, flexor sheaths of toes
What is are the functions of the plantar aponeurosis?
Protection of deeper structures of the foot, to maintain longitudinal arch, for muscular attachment
What two veins drain the dorsal venous arch of the foot?
Great (Medially) and lesser (laterally) saphenous veins
What is the crural fascia?
The deep fascia of the leg, continuous with the fascia lata, distally forms the extensor and flexor retinaculum
Which muscles make up the anterior compartment of the leg?
Tibialis anterior, extensor digitorum longus, extensor hallucis longus, fibularis tertius
What are the attachments to tibialis anterior?
O: lateral surface of tibia, interosseous membrane
I: Medial cuneiform bone, base of metatarsal 1
What is the innervation to tibialis anterior?
Deep fibular nerve (L4,5)
What are the actions of tibialis anterior?
Talocrural joint: Foot dorsiflexion. Subtalar joint: inversion
What are the attachments of extensor digitorum longus?
O: proximal half of medial fibula, lateral tibial condyle, interosseous membrane
I: distal and middle phalanges of digits 2-5
What are the actions of extensor digitorum longus?
Toe extension of MTP, IP joints 2-5
Foot dorsiflexion
Foot eversion
What is the innervation to extensor digitorum longus?
Deep fibular nerve (L5, S1)
What are the attachments of extensor hallucis longus?
O: middle 1/3rd of medial surface of fibula, interosseous membrane
I: Base of distal phalanx of great toe
What are the actions of extensor hallucis longus?
MTP, IP of great toe extension, foot dorsiflexion
What is the innervation to extensor hallucis longus?
Deep fibular nerve (L5, S1)
What are the attachments of fibularis tertius?
O: distal 1/3rd of medial surface of fibula, interosseous membrane
I: dorsal surface of base of metatarsal 5
What are the actions of fibularis tertius?
Dorsiflexion
Eversion
What is the innervation to fibularis tertius?
Deep fibular nerve (L5, S1)
Where does the dorsalis pedis artery run?
Lateral to the extensor hallucis tendon on the dorsal surface of the foot
Which artery is the main contribution to the deep plantar arch?
The deep plantar artery, from the dorsalis pedis
What are the attachments of extensor digitorum brevis?
O: superolateral aspect of calcaneus
I: Extensor digitorum longus tendons of toes 2-4
What are the actions of extensor digitorum brevis?
Extension of distal interphalangeal joints of toes 2-4
What is the innervation to extensor digitorum brevis?
Deep fibular nerve (L5, S1)
What are the attachments of extensor hallucis brevis?
O: superolateral surface of calcaneus bone
I: proximal phalanx of great toe
What is the action of extensor hallucis brevis?
Extension of the metatarsophalangeal joint of the big toe
What is the innervation to extensor hallucis brevis?
Deep fibular nerve (S1,2)
Where is the arcuate artery found?
It is the dorsal arterial arch of the foot, it comes off the dorsalis pedis artery
Where is the lateral tarsal artery?
It is a branch of dorsalis pedis, it travels laterally and anastamoses to form the arcuate artery
Where do the dorsal digital arteries lie?
Either side of the phalanges on the dorsum of the foot
Where does the deep plantar artery run?
At the base of the metatarsal bones, in between digit 1 and 2. A branch of dorsalis pedis
What are the attachments of the dorsal interossei?
O: sides of metatarsal bones 1-5
I: 1. Medial base of proximal phalanx of digit
2-4. lateral bases of proximal phalanges and extensor expansion
What are the actions of the dorsal interossei?
MTP joints 2-4: flexion, abduction
IP joints 2-4: extension
What is the innervation to the dorsal interossei?
Lateral plantar nerve (S2-S3)
How many dorsal interossei are there?
Four
What are the muscles of the lateral compartment of the leg?
Fibularis longus and brevis
What are the attachments of fibularis longus?
O: head of fibula, proximal 2/3rds of lateral surface of fibula
I: Medial cuneiform bone, metatarsal bone 1
What are the actions of fibularis longus?
Talocrural joint: foot plantar flexion
Subtalar joint: foot eversion
Also supports foot arches
What is the innervation to fibularis longus and brevis?
Superficial fibular nerve (L5,S1)
What are the attachments to fibularis brevis?
O: distal 2/3rds of lateral surface of fibula, intermuscular septum
I: Tuberosity of the 5th metatarsal bone
What are the actions of fibularis brevis?
Talocrural joint: foot plantar flexion
Subtalar joint: Foot eversion
What is the blood supply to fibularis longus and brevis?
Brevis: anterior tibial
Longus: fibular artery
Where can you find the small saphenous vein at the ankle?
Posterior to the lateral malleolus
Where does the tibial nerve and posterior tibial vessels run in relation to soleus?
Deep to it
What muscles make up the deep compartment of the posterior leg?
Flexor digitorum longus, flexor hallucis longus, tibialis posterior
What are the attachments of flexor digitorum longus?
O: posterior surface of tibia (inferior to soleal line)
I: Bases of distal phalanges of digits 2-5
What are the actions of flexor digitorum longus?
MTP and IP of 2-5: flexion
Talocrural joint: foot plantarflexion
Subtalar joint: foot eversion
What is the innervation to flexor digitorum longus?
Tibial nerve (L5, S1, S2)
What is the blood supply to the deep posterior compartment of the leg?
Posterior tibial artery, fibular artery
What are the attachments of flexor hallucis longus?
O: distal 2/3rds of posterior surface of fibula, interosseous membrane
I: base of distal phalanx of great toe
What is the innervation to flexor hallucis longus?
Tibial nerve (S2,3)
What are the actions of flexor hallucis longus?
MTP and IP joint 1: flexion
Talocrural joint: plantarflexion
Subtalar joint: inversion
What are the attachments of tibialis posterior?
O: posterior surface of tibia, posterior surface of fibula and interosseous membrane
I: tuberosity of navicular, all cuneiform bones, cuboid bone, bases of metatarsal bones 2-4
What are the actions of tibialis posterior?
Talocrural joint: plantarflexion
Subtalar joint: inversion
What is the innervation of tibialis posterior?
Tibial nerve (L4, 5)
What are the positions of the deep muscles of the posterior leg from medial to lateral?
Medial: Flexor digitorum longus, tibialis posterior, flexor hallucis longus :Lateral
Does popliteus travel medially or laterally?
Medially - inserts onto the tibia from lateral epicondyle of femur
What are the contents of the tarsal tunnel from anterior to posterior?
Tom, Dick and A Very Nervous Harry
Tibialis posterior, flexor digitorum longus, posterior tibial artery and vein, tibial nerve, flexor hallucis longus
Where on the foot is the tarsal tunnel found?
On the posteromedial ankle, behind the medial malleolus
What are the borders of the tarsal tunnel?
Floor: medial aspect of tibia, talus, calcaneus
Roof: flexor retinaculum from medial malleolus to medial tubercle of calcaneus
Which muscles are innervated by the medial plantar nerve?
LAFF - first lumbrical, abductor hallucis, flexor digitorum brevis, flexor hallucis brevis
Which muscles are innervated by the lateral plantar nerve?
All intrinsic muscles of the foot except abductor hallucis, flexor digitorum brevis, flexor hallucis brevis and the 1st lumbrical muscle
What area of skin is supplied by the lateral plantar nerve?
Lateral sole of foot, plantar surface of 5th and half of 4th toe
What area of skin is supplied by the medial plantar nerve?
Medial 3 and medial half of fourth toe. supplies tips of toes on dorsum also
Which muscles make up the first layer of plantar muscles?
Flexor digitorum brevis, abductor hallucis, abductor digiti minimi
What are the attachments of flexor digitorum brevis?
O: medial process of calcaneal tuberosity, plantar aponeurosis and intermuscular septum
I: Middle phalanges of digits 2-5
What are the actions of flexor digitorum brevis?
MTP joints 2-5: Toe flexion
What is the innervation to flexor digitorum brevis?
Medial plantar nerve (S1-S3)
What are the attachments of abductor hallucis?
O: Medial process of calcaneal tuberosity, flexor retinaculum, plantar aponeurosis
I: Base of proximal phalanx of great toe
What are the actions of abductor hallucis?
MTP joint 1: toe abduction, flexion
What is the innervation to abductor hallucis?
Medial plantar nerve (S1-S3)
What are the attachments of abductor digiti minimi?
O: calcaneal tuberosity, plantar aponeurosis
I: Base of proximal phalanx of digit 5, metatarsal bone 5
What are the actions of abductor digiti minimi?
MTP joint 5: abduction and flexion
What is the innervation to abductor digiti minimi?
Lateral plantar nerve (S1-S3)
Which artery are the medial and lateral plantar arteries branches of?
The posterior tibial artery - it travels posterior to the medial malleolus
Which artery contributes most of the blood supply to the plantar surface of the digits?
Lateral plantar artery - contributes most to the plantar arch
Between which layers of the foot do the posterior tibial nerve and artery run?
Between layers 1 and 2
Which muscles make up the second layer of plantar foot muscles?
Quadratus plantae and lumbricals
What are the attachments of quadratus plantae?
O: medial surface of calcaneus, lateral process of calcaneal tuberosity
I: Tendon of flexor digitorum longus
What are the actions of quadratus plantae?
MTP joints 2-5: toe flexion - via flexor digitorum longus tendon
What is the innervation to quadratus plantae?
Lateral plantar nerves (S1-S3)
What are the attachments of the lumbricals?
O: tendons of flexor digitorum longus
I: Medial bases of proximal phalanges and extensor expansion of digits 2-5
What are the actions of the lumbricals?
MTP joints 2-5: flexion, adduction
IP joints 2-5: extension
What is the innervation to the lumbricals?
Lumbrical 1: medial plantar nerve (S2,3)
Lumbricals 2-4: Lateral plantar nerve (S2,3)
Which muscles are in the third layer of the plantar muscles?
Flexor hallucis brevis, adductor hallucis, flexor digiti minimi
Which tendon usually contains the sesamoid bones of the hallux?
Flexor hallucis brevis
What are the attachments of flexor hallucis brevis?
O: tendon of tibialis posterior, medial, lateral cuneiform, cuboid bone
I: Lateral and medial aspects of the proximal phalanx of the big toe
What are the actions of flexor hallucis brevis?
MTP joint 1: Toe flexion
What is the innervation to flexor hallucis brevis?
Medial plantar nerve (S1, S2)
Where does the tendon of flexor hallucis longus lie in relation to flexor hallucis brevis?
Longus lies on top of and in between the two heads of brevis, brevis attaches to proximal phalange whereas longus attaches to the distal phalange
What are the attachments of adductor hallucis?
O: Oblique head: bases of metatarsal bones 2-4, cuboid, lateral cuneiform, tendon of fibularis longus
Transverse head: Plantar MTP and deep transverse ligaments of toes 3-5
I: lateral aspect of base of proximal phalanx of great toe
What are the actions of adductor hallucis?
MTP joint 1: Adduction, flexion
What is the innervation to adductor hallucis?
Lateral plantar nerve (S2,3)
What are the attachments of flexor digiti minimi brevis?
O: base of metatarsal bone 5
I: base of proximal phalanx of little toe
What is the action of flexor digiti minimi brevis?
MTP joint flexion of little toe
What is the innervation to flexor digiti minimi brevis?
Lateral plantar nerve (S2,3)
The deep plantar arch sits between which layers?
Under adductor hallucis (3rd layer) and above the interosseous muscles
Which two arteries anastamose to form the deep plantar arch?
The medial and lateral plantar arteries
How many plantar interosseous muscles are there?
three
Which muscles are in the fourth layer of plantar muscles?
Plantar and dorsal interossei
What are the attachments of the plantar interossei?
O: medial bases of metatarsal bones 3-5
I: medial bases of proximal phalanges and extensor expansion of digits 3-5
What are the actions of the plantar interossei?
MTP joints 3-5: flexion, adduction
IP joints 3-5: extension
What is the innervation to the plantar and dorsal interossei?
Lateral plantar nerve (S2-3)
Adduction and abduction of the foot takes place around which toe?
The second toe
How many dorsal interossei are there?
Four
What are the attachments of the dorsal interossei?
O: opposing sides of metatarsal bones 1-5
I: 1. Medial base of proximal phalanx. 2-4. lateral bases of proximal phalanges and extensor expansions
What are the actions of the dorsal interossei?
MTP joints 2-4: toe flexion, abduction
IP joints 2-4: toe extension
Which ligament holds the tendon of fibularis longus in place?
The long plantar ligament
Which tendon is seen deep to the plantar muscles travelling transversely across the foot?
Fibularis longus tendon - from lateral to medial helps to form transverse plantar arch
What are the three arches of the foot?
Medial, lateral longitudinal and transverse arch
Which structures form the transverse arch?
Bones: metatarsals 1-5, cuboid and cuneiform bones
Ligaments: ligaments of intercuneiform joints
Muscles: fibularis longus, tibialis posterior
Which structures form the medial longitudinal arch?
Bones: metatarsals 1-3, sesamoid bones, cuneiform bones, navicular, talus and calcaneus bones
Ligaments: plantar aponeurosis, spring ligament, talocalcaneal ligament, deltoid ligament
Muscles: flexor hallucis longus, flexor digitorum longus, abductor hallucis, flexor digitorum brevis, tibialis posterior
Which structures form the lateral longitudinal arch?
Bones: calcaneus, cuboit, metatarsals 4-5
Ligaments: plantar aponeurosis, plantar ligaments
Muscles: fibularis longus, abductor digiti minimi, lateral half of flexor digitorum brevis, fibularis brevis, fibularis tertius
What are the three lateral ligaments of the foot?
Anterior, posterior talofibular, calcaneofibular
What are the four parts of the deltoid/medial ligament of the foot?
anterior, posterior talotibia, tibiocalcaneal, tibionavicular
What are the three retinacula of the foot?
Extensor, fibular, flexor
Where is the superior extensor/fibular retinaculum?
From fibula to tibia, proximal to the malleolus
Where is the inferior extensor retinaculum?
Y-shaped. From anterosuperior surface of calcaneus to medial malleolus, and deep fascia of the foot
Where is the flexor retinaculum of the ankle?
From medial aspect of calcaneus to medial malleolus (forming tarsal tunnel)
What is the spring ligament?
The ligament between calcaneus and navicular on the plantar surface of the foot
Which ligament is most commonly damaged by over inversion?
Anterior talofibular
Sensation to the lateral foot is innervated by which nerve?
Sural
