Week 8 - the lower leg Flashcards
Joints of the tibia and fibular and classifications of each joint
Proximal tibiofibular joint (synovial) and distal/inferior tibiofibular joint (syndesmosis/fibrous)
What structure lies between the tibia and fibular?
Interosseous membrane
What type of movements occur at the tibiofibular joints?
Gliding movements
How many tarsals, metatarsals and phallanges of the foot? Name the tarsals.
7 tarsals, 5 metatarsals, 14 phalanges
Calcaneus, talus, navicular, cuboid, 3 cuneiform (medial, middle, lateral)
Metatarsal head are proximal or distal?
Distal, base is more proximal
What bone does the distal tibia and fibula articulate with?
Talus
What is the heel bone of the foot?
Calcaneus, inferior to the Talus
Third bone that articulates with the Talus and Calcaneus on the medial side?
Navicular
Bone lateral to Navicular
Cuboid
3 bones anterior to the Navicular and medial to cuboid
3 Cuneiforms
3 bones anterior to the Navicular and medial to cuboid
3 Cuneiforms
How many phallenges does the Hallux have?
2, the other toes have 3
What muscles does the tibial nerve innovate?
Posterior leg
Knee flexors, plantarflexors and toe flexors
Gastrocnemius, Soleus, Plantaris, Popliteus, Tibialis posterior, Flexor digitorum longus, Flexor hallicis longus
What muscles does the superficial fibular nerve innervate?
Lateral leg
Ankle everters & weak plantarflexors
Fibularis longus, fibularis brevis
What does the deep fibular nerve innervate?
Anterior leg
Toe extensors, ankle dorsiflexors and inverters
Tibialis anterior, Extensor hallucis longus, Extensor digitorum longus, Fibularis tertius
Gastrocnemius
Proximal & distal attachments
Action & nerve innveration
Proximal:
Lateral head: lateral condyle of femur
Medial head: posterior surface of
femur, superior to medial condyle
Distal: calcaneal tendon – posterior
surface of calcaneus
Action: knee flexion and ankle
plantarflexion
NS: tibial nerve
Soleus
Proximal and distal attachments
action and nerve innervation
Attachments:
P: posterior aspect of head of
fibula, soleal line, and middle
1/3 of medial border of tibia
D: calcaneal tendon – posterior
surface of calcaneus
Action: ankle plantarflexion
NS: tibial nerve
Plantaris
Action & N. innervation
Action: weak plantarflexor
NS: tibial nerve
What is the achilles tendon called to anatomists?
Calcaneal tendon
Popliteus
P. & D. Attachments
Action & N. innervation
Attachments:
P: lateral condyle of femur
D: posterior surface of tibia,
superior to soleal line
Action: “unlocks knee”
NS: tibial nerve
Tibialis posterior
P. & D. Attachments
Action & NS
Attachments:
P: interosseous membrane (IOM),
posterior surface of tibia and fibula
D: tuberosity of navicular and across
the plantar surface of the foot
(cuneiform, cuboid, calcaneum) to the
base of 2nd-4th metatarsals
Action: ankle plantarflexion and
inversion
NS: tibial nerve
Flexor digitorum longus
P. & D. Attachments
Action & NS
Attachments:
P: medial posterior surface of tibia
D: plantar surface of distal phalanges
of lateral 4 digits
Action: flexion of lateral 4 toes and
ankle plantarflexion
NS: tibial nerve
Flexor Hallucis Longus
P. & D. Attachments
Action & NS
Attachments:
P: posterior surface of fibula and
inferior IOM
D: plantar surface distal phalanx of
hallux (big toe)
Action: flexion of hallux, weak
ankle plantarflexion
NS: tibial nerve
Lateral muscles of lower leg and actions of the foot?
Fibularis longus, fibularis brevis
Everters of the foot
Fibularis Longus
P. & D. attachments
Action & NS
Attachments:
P: head and superior 2/3 of lateral
surface of fibula
D: plantar surface of base of 1st
metatarsal and medial cuneiform
Action: ankle eversion and
plantarflexion
NS: superficial fibular nerve
Fibularis Brevis
P. & D. Attachments
Action & NS
Attachments:
P: inferior 2/3 of lateral surface of
fibula
D: lateral surface of base of 5th
metatarsal
Action: ankle eversion and
plantarflexion
NS: superficial fibular nerve
Which muscle has the greater capacity to exert everter force? and why?
Fibularis longus
It has a longer MA meaning it can generate more force at the joint
Sprained ankle is when the ankle is taken into hyper inversion. What muscle helps to protect against that?
Fibularis Longus
Anterior muscles of the lower leg and action
Tibialis anterior, Extensor digitorum longus, Extensor hallucis longus, Fibularis tertius
Dorsiflexors
Tibialis anterior
P. & D. Attachments
Action & NS
Attachments:
P: lateral condyle and superior half
of lateral surface of tibia and
interosseous membrane (IOM)
D: medial and plantar surface of
medial cuneiform and base of 1st
metatarsal
Action: ankle dorsiflexion and
inversion
NS: deep fibular nerve
Extensor Hallucis Longus
P. & D. Attachments
Action & NS
Attachments:
P: middle part of anterior surface of
fibula and IOM
D: dorsum of distal phalanx of hallux
Action: ankle dorsiflexion and hallux
extension
NS: deep fibular nerve
Extensor Digitorum Longus
P. & D. Attachments
Action & NS
Attachments:
P: lateral condyle of tibia, superior
surface of fibula and IOM
D: dorsum of middle and distal
phalanges 2-5
Action: ankle dorsiflexion and extension
of digits 2-5
NS: deep fibular nerve
Fibularis Tertius
P. & D. Attachments
Action & NS
Attachments:
P: inferior anterior surface of fibula
and IOM
D: dorsum of base of 5th metatarsal
Action: ankle dorsiflexion and
eversion
NS: deep fibular nerve
What is the extensor retinaculum?
Fibrous, thickened band that holds the extensor tendons at the dorsum of the ankle and wrist.
It has a superior and inferior band and acts as a pulley system
Tibial nerve course
- Passes anterior to the arch of soleus with the
popliteal artery and descends into the leg - Descends with the posterior tibial vessels to
lie between the calcaneus and medial
malleolus overlapped by Flexor Hallucis
Longus (FHL) - Beneath the flexor retinaculum
- Divides into the medial and lateral plantar
nerves
Tibial nerve distribution - muscular branches supply
– Gastrocnemius
– plantaris
– popliteus
– soleus
– tibialis posterior
– flexor digitorum longus
– flexor hallucis longus
Tibial nerve distribution - sensory (cutaneous) branches
– sural nerve
– medial calcaneal nerve
Common fibular nerve course
- Passes into the anterolateral
compartment of the leg
– over gastrocnemius
– by curving lateral to the fibular
neck,
– deep to fibularis longus, and
– dividing into a deep and superficial
branch - Supplies lateral knee joint
Superficial fibular nerve distribution - muscles
– fibularis longus
– fibularis brevis
Deep fibular nerve distribution - muscles
− tibialis anterior
− extensor digitorum longus
− extensor hallucis longus
− fibularis tertius
Deep fibular nerve also innervates which joint?
Proximal tibiofibular joint
