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Flashcards in Posterior Leg Deck (28)
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1
Q

What are the muscular insertion sites (that are also palpable) on the femur for muscles of the posterior leg? (2)

A
  • medial epicondyle
  • lateral epicondyle
2
Q

What is the muscle insertion site on the tibia of posterior muscles and palpable features (2) on the tibia and fibula?

A
  • muscle insertion: soleal line
  • palpable features: medial malleolus, lateral malleolus
3
Q

What is the muscle insertion site and palpable feature on the foot for posterior leg? (superior view)

What are the muscle insertion sites for posterior leg muscles on the foot? (inferior view)

A
  • superior: calcaneal tuberosity (posterior surface)
  • inferior: flexor digitorum longus, flexor longus, tibialis posterio
4
Q

What does the posterior process of the talus bone of foot contain? (3 structures)

A
  • lateral tubercle
  • medial tubercle
  • groove for flexor hallucis longus tendon
5
Q
  • largest foot bone that articulates with: talus (superiorly) and cuboid (anteriorly)
  • contains the sustentaculum tali (L., support of the talus)
A

calcaneus B.

6
Q
  • a part of the calcaneus B.
  • shelf-like projection that supports talus and provides groove for flexor hallucis longus
A

sustentaculum tali

7
Q

What bones does the navicular B. articulate with? (3)

What does the navicular tuberosity provide attachment for?

A
  • articulates: talus head (posteriorly), 3 cuneiforms (anteriorly), cuboid (laterally)
  • attachment: tibialis posterior
8
Q

What provides dynamic arch support to the foot?

What 2 structures provide the most dynamic support?

What provides passive arch support to the foot?

A
  • dynamic support provided by tendons
  • most dynamic support: tibialis posterior, flexor hallucis longus
  • passive support provided by ligaments
9
Q

What are the compartments in the leg that are separated by septa?

How are the compartments characterized?

What is the characterization of the septa? How does it change with age?

How is blood circulated against gravity in the leg?

A
  • compartments: anterior, lateral, posterior (superficial and deep separated by transverse septum)
  • compartments share: same general function, innervation, and artery/vein flow
  • septa (or deep crural fascia) in the leg is quite thick, although it becomes more laxed with age (cause of increased fluid retention (edema) with age)
  • muscle contraction in the leg, with the help of valves, pushes blood back up to the heart against gravity
10
Q

(From a previous lecture)

What is the action and innervation of the thigh compartments? (medial, anterior, posterior)

A
  • medial: adduction at hip, obturator N.
  • anterior: extension at knee, femoral N.
  • posterior: flexion at knee, sciatic N.

(thigh compartment separation is less dramatic compared to leg separation)

11
Q

What septa divides the posterior leg compartment?

What are the 2 posterior leg compartments and their contents?

What nerves and vessels supply innervation and vascularization to the posterior leg?

A
  • transverse septa divides groups:
  1. superficial posterior group: gastrocnemius, soleus (triceps surae), plantaris
  2. deep posterior group: popliteus, flexor hallucis longus, flexor digitorum longus, tibialis posterior
  • tibial N. and posterior tibial A. and V. (located deep to transverse crural intermuscular septum)

(photo view is inferior from foot)

12
Q
  • most superficial posterior compartment leg muscle
  • two-headed muscle that crosses the knee and ankle joints
  • medial head: superior to medial femoral condyle, slightly larger (extends slightly further distally)
  • lateral head: lateral aspect superior to lateral femoral condyle
A

gastrocnemius

13
Q

Gastrocnemius M.

Origin:

Insertion:

Action:

Innervation:

A

- Origin:

  • medial head: superior to medial femoral condyle
  • lateral head: lateral aspect superior to lateral femoral condyle
  • Insertion: posterior surface of calcaneus via tendo calcaneus (achilles tendon)
  • Action: plantar flexion and flexes leg at knee joint
  • Innervation: tibial N.
14
Q

What is the clinical relevance of fabella (sesamoid bone close to the proximal attachment of lateral gastrocnemius)?

A
  • the bone possibly provides leverage for lateral head of gastrocnemius
  • painful flabellar stress fracture may accompany total knee replacement
15
Q

Soleus M.

Origin:

Insertion:

Action:

Innervation:

A

Soleus M. (broad, flat multipennate (L., sandal) muscle; lies deep to gastrocnemius)

- Origin: horseshoe-shaped proximal attachments (soleal line of tiba, posterior head of fibula and superior 1/4 of posterior fibula)

- Insertion: posterior surface of calcaneus via tendo calcaneus (achilles tendon)

- Action: plantarflexion

- Innervation: tibial N.

(form a tripartite muscle with gastrocnemius, known as “triceps surae” which forms calf prominence)

16
Q

Plantaris M.

  • Origin:
  • Insertion:
  • Action:
  • Innervation:
A

Plantaris M. (small muscle, short belly and long tendon, often absent)

- Origin: lateral end of lateral supracondylar line (long tendon runs between gastroc and soleus)

- Insertion: posterior surface of calcaneus via calcaneal tendon

- Action: weak plantarflexion/leg flexion, proposed to be a proprioceptive organ for foot position (due to high density of proprioceptive receptor end organs)

- Innervation: tibial N.

17
Q

Why is the plantaris M. commonly used in hand reconstructive surgeries?

What are possible plantaris M. injuries?

A
  • used in hand surgery because its removal does not affect ankle or knee movements (allegedly), although it has been implicated in foot positive proprioception so this is not definite
  • it can be injured during violent ankle movements (sudden dorsiflexion), which is common in basketball players, sprinters, and ballet dancers (causes severe pain)
18
Q

Popliteus M.

  • Origin:
  • Insertion:
  • Action:
  • Innervation:
A

Popliteus M. (thin, flat, triangular muscle; lies deep to plantaris; forms inferior floor of popliteal fossa)

  • Origin: posterior tibia (superior to soleal line)
  • Insertion: lateral surface of lateral femoral condyle and lateral meniscus
  • Action: unlocks extended leg by laterally rotating femur on a stationary tibia; flexes leg weakly
  • Innervation: tibial N.
19
Q

What are the locations of:

  • superior medial and superior lateral genicular As.:
  • inferior medial genicular A.:
  • inferior lateral genicular A.:
A
  • superior medial and superior lateral genicular As.: superior to medial and lateral heads of gastrocnemius
  • inferior medial genicular A.: deep to medial head of gastroc
  • inferior lateral genicular A.: deep to plantaris and superficial to popliteus
20
Q

Flexor hallucis longus

  • Origin:
  • Course:
  • Insertion:
  • Action:
  • Innervation:
A

Flexor hallucis longus (largest deep posterior muscle, lies deep to soleus)

- Origin: inferior 2/3 of posterior fibula,

  • Course: passes inferiorly deep to flexor retinaculum, occupies shallow groove on sustentaculum tali, crosses deep to FDL tendon in sole of foot (tendinous slip to FDL), approaches great toe between sesamoid bones in FHB tendons

- Insertion: base of distal phalanx of great toe

- Action: flexes great toe, plantarflexes foot at ankle joint

- Innervation: tibial N.

21
Q

Flexor digitorum longus

  • Origin:
  • Course:
  • Insertion:
  • Action:
  • Innervation:
A

Flexor digitorum longus (deep to soleus and posterior to tibia)

  • Origin: posterior tibia (inferior to soleal line)
  • Course: tendon passes posterior to tibialis posterior, passes diagonally in sole of foot (superficial to FHL tendon), near middle of sole it divides into four tendons that pass to lateral four digits
  • Insertion: distal phalanx base of lateral four digits
  • Action: flexes lateral four digits, plantarflex foot at ankle joint
  • Innervation: tibial N.
22
Q

Tibialis posterior

  • Origin:
  • Course:
  • Insertion:
  • Action:
  • Innervation:
A

Tibialis posterior (deepest posterior crural muscle, same plane as leg bones, lies between FDL and FHL)

  • Origin: inerosseous membrane, posterior tibia inferior to soleal line, posteromedial surface of fibula)
  • Course: passes anterior to FDL
  • Insertion: (various tarsal and metatarsal bones) navicular tuberosity, cuneiforms, 2-4 metatarsal bones
  • Action: inversion, plantarflexion
  • Innervation: tibial N.
23
Q

What does Tom, Dick, an, Harry pneumonic stand for in terms of posterior leg anatomy?

A

(a way to remember the order of deep tendons/muscles in the posterior leg)

Tom: tibialis posterior

Dick: flexor digitorum longus

a: posterior tibial A.
n: tibial N.

Harry: flexor hallucis longus

24
Q

What is the path of the tibial N.?

A
  • passes w/ posterior tibial vessels (deep to soleus, posterior to tibialis posterior)
  • leaves posterior compartment by passing deep to flexor retinaculum between medial malleolus and calcaneus
  • ends by dividing into medial and lateral plantar nerves (posteroinferior to medial malleolus)
25
Q

What is the path of the posterior tibial A. to supply the posterior leg?

A
  • starts as popliteal A. which divides into posterior tibial A.
  • begins near inferior border of popliteus (deep to soleus), gives rise to fibular A.
  • passes inferomedially on posterior surface of tibialis posterior with tibial N.
  • runs deep to flexor retinaculum and vascularizes posterior compartment
  • ends by dividing into medial and lateral plantar As.
26
Q

What is the largest branch of posterior tibial A.? What is the path of this A.?

A

fibular A.

  • begins inferior to distal border of popliteus
  • descends obliquely toward fibula, usually under FHL
  • ends by piercing interosseus membrane and anastomosing w/ anterior lateral malleolar A.
  • vascularizes posterior and lateral compartments
27
Q

How do you tell whether the posterior tibial A. is supplying the posterior leg adequately?

A
  • palpate posterior tibial pulse: posterior surface of medial malleolus, medial border of calcaneal tendon, deep to flexor retinaculum

(important to have patient relax retinaculum by inverting foot)

28
Q

What is the posterior tibial pulse used to examine?

A
  • patients w/ occlusive peripheral artery disease (intermittent claudication)
  • caused by ischemia of leg muscles due to narrowing or occlusion of leg arteries
  • characterized by leg cramps and pain during walking (disappears after rest)