Thigh, Leg, Foot Flashcards
1
Q
Which muscles flex the thigh at the hip?
A
- strongest = iliopsoas
- sartorius (also abducts and laterally rotates the thigh. It also flexes the leg at the knee)
- rectus femoris (the other vastus quadriceps only extend leg at knee)
-
pectineus (also adducts)
- All innervated by femoral nerve
2
Q
quadriceps:
What are the 4 muscles?
Innervation?
Action?
A
Quads =
- Rectus femoris
- Vastus lateralis
- Vastus intermedius
- Vastus medialis
- All innervated by femoral nerve (L2-L4)
- All cause extension of the leg at the knee
- The rectus femoris also crosses the hip joint and is a flexor of the thigh at the hip
3
Q
anterior thigh - what are the 3 major muscles?
What are they innervated by?
A
- There are 3 major muscles in the anterior thigh – the pectineus, sartorius and quadriceps femoris
- All innervated by the femoral nerve
- Sartorius muscle = a flexor of the thigh at the hip and a flexor of the leg at the knee. It also causes external rotation of the thigh.
- Quadriceps muscles = rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis. These muscles cause extension of the leg at the knee; the rectus femoris also crosses the hip joint and is a flexor of the thigh at the hip.
- Pectineus = a flexor and adductor of the thigh at the hip.
4
Q
rectus femoris
A
- One of the quadriceps muscles.
- Part of anterior thigh, innervated by femoral nerve (L2-L4)
- In addition to causing extension of leg at the knee, also crosses the hip joint and is a flexor of the thigh at the hip
5
Q
pectineus muscle
A
- Pectineus is a flexor and adductor of the thigh at the hip.
- Part of the anterior thigh, innervated by posterior fibers of the femoral nerve
6
Q
Dermatome of femoral nerve?
A
- The dermatome of the femoral nerve = the skin of the anterior to anteromedial thigh.
- As the femoral nerve reaches the inferior aspect of the thigh, it continues as a cutaneous-only nerve, the saphenous nerve, which provides cutaneous innervation to the anteromedial leg.
- (Note the parallelism to the musculocutaneous nerve of the upper limb)
7
Q
Dermatome of obturator nerve?
A
- A small ovoid area on the inferomedial thigh.
8
Q
medial thigh:
What are the 3 muscles, what do they all do?
Innervation?
A
- Medial thigh is innervated by obturator nerve
- The medial compartment consists of three adductors:
- adductor brevis
- adductor longus
- adductor magnus.
- These 3 muscles are all adductors of the thigh at the hip.
- The adductor magnus also can extend the thigh at the hip and flex the leg at the knee.
- Medial compartment also includes 2 other adductor muscles innervated by obturator: gracilis and obturator externus
9
Q
adductur magnus
A
- One of the three muscles of medial thigh
- Innervated by obturator nerve
- In addition to acting as adductor of the thigh at the hip, the adductor magnus also can extend the thigh at the hip and flex the leg at the knee
10
Q
obturator externus
- Compartment?
- Innervation?
- Actions?
A
- Part of medial thigh, innervated by obturator nerve
- Adductor of thigh at hip, and also…
- Lateral rotator of the thigh at the hip
11
Q
Sciatic nerve:
What is it, where does it split?
A
- Sciatic nerve = part of lumbosacral plexus (L4-S3)
- Exits just inferior to the piriformis muscle.
- When the sciatic nerve reaches the superior border of the popliteal fossa, it splits into the tibial nerve and common fibular nerve.
- The tibial nerve continues straight down, whereas the common fibular nerve swings laterally to pass over the neck of the fibula.
12
Q
quadriceps vs. hamstrings
A
- They’re antagonists
- The quadriceps is the group of four muscles at the front of the thigh.
- Innervated by femoral nerve
- The vastus lateralis, vastus medialis, vastus intermedius, and the rectus femoris
- The hamstrings are three muscles at the back of the thigh.
- All of the true hamstrings (those that cross both the hip and knee joints) are innervated by the tibial nerve, and cause extension of the thigh at the hip and flexion of the leg at the knee. These include the semitendinosus, semimembranosus, and the long head of the biceps femoris. The short head of the biceps femoris (not a true hamstring) is innervated by the common fibular nerve.
13
Q
describe movements at hip joint
A
14
Q
movements at knee joint
A
15
Q
movements at ankle joint
A
16
Q
What causes eversion of the foot?
A
- The superficial fibular nerve innervates the lateral compartment of the leg, which cause eversion of the foot.
- Eversion = turn sole of foot outwards
- There are two muscles in the lateral compartment of the leg; the fibularis longus and brevis (aka peroneal longus and brevis).
18
Q
What are the 3 compartments of the thigh?
3 compartments of the leg?
(Muscles in the same compartment tend to share the same innervation and blood supply.)
A
Thigh:
- Anterior compartment - Femoral nerve
- Medial compartment - Obturator nerve
-
Posterior compartment - Tibial nerve
- Except the short head of the biceps, which is innervated by common fibular nerve
- Blood supply for all = deep femoral artery. Posterior compartment gets the perforating branches.
Leg:
-
Anterior compartment - Deep fibular nerve
- Anterior tibial artery
-
Lateral compartment - Superficial fibular nerve
- Fibular artery
-
Posterior compartment - Tibial nerve
- Posterior tibial artery
- (All the blood supply are divisions of the popliteal artery, which is the name for the femoral artery once it passes through adductur hiatus.)
23
Q
Name nerves that contribute to
cutaneous innervation of the leg?
A
-
common fibular nerve
- Includes superficial fibular nerve
- Gives off lateral sural nerve.
- (Also includes deep fibular nerve, but that’s just the flip flop.)
-
femoral nerve
- Continues into the leg as the saphenous nerve
- superficial fibular nerve
- tibial nerve
24
Q
bones that comprise knee joint
A
- the knee joint is formed from the two femoral condyles (a lateral and a medial one) sitting atop the tibial plateau.
- Tibia = main weight-bearing bone
25
Q
muscles for flexion and extension at knee
A
- flexion = hamstring muscles of the posterior thigh and the gastrocnemius of the posterior leg,
- extension = quadriceps muscles of the anterior thigh.
26
Q
name ankle joint and two foot joints
and the major bones
A
- The talocrural joint of the ankle is a hinge joint that is stabilized by large bony protuberances: the lateral malleolus (fibula) and the medial malleolus (tibia).
- just plantar and dorsal flexion
- two gliding joints in the foot:
- the subtalar joint lies between the talus and the calcaneus.
-
two transverse tarsal joints: the navicular articulates with the talus and the cuboid articulates with the calcaneus.
- Inversion and eversion occur at the transverse tarsal and subtalar joints.
27
Q
muscles of anterior leg and dorsal foot
- innervation, blood supply
- actions
A
- The muscles of the anterior leg are primarily dorsiflexors, with some inversion ability as well.
- All muscles in this compartment are innervated by the deep fibular nerve and receive their blood supply from the anterior tibial artery.
- Remember that the superficial and deep fibular nerves split just after the common fibular nerve passes the neck of the fibula; the anterior and posterior tibial arteries split from the popliteal artery near the superior aspect of the interosseus membrane and ride down its respective anterior and posterior surfaces.
- tibialis anterior, which dorsiflexes and also everts, given its insertion on the medial foot.
- extensor digitorum longus is analogous to the extensor digitorum of the posterior forearm, and causes extension of the metatarsophalangeal joints (MTP) of digits 2 through 5.
- The extensor hallucis longus also causes extension at the MTP of the hallux (big toe); it also is a weak inverter of the foot.
- The compartment of the dorsal foot should be thought of as an extension of the anterior leg; the two muscles in it (extensor digitorum brevis and extensor hallucis brevis) fuse their tendons with the “longus” versions of the same muscles and simply provide assistance to these muscles.
28
Q
muscles of posterior leg
- innervation, blood supply
- actions
A
- The posterior leg muscles are all plantar flexors.
- all share the same innervation and blood supply: the tibial nerve and the posterior tibial artery
- The plantaris is a rather thin muscle that sends a long, narrow tendon down to the calcaneus (the longest tendon in the body); it is actually absent in approximately 10% of the population.
- The bulk of the posterior leg compartment consists of the gastrocnemius and soleus muscles, which merge their tendons to form the Achilles tendon that inserts onto the calcaneus.
- gastrocnemius also crosses the knee joint, and is a minor flexor of the leg at the knee.
- The popliteus muscle is a weak flexor of the leg at the knee, but is better known for its role in laterally rotating the femur to unlock the knee.
- The tibialis posterior causes plantar flexion and also inverts the foot, given its insertion onto the medial foot.
- The flexor digitorum longus is analogous to the flexor digitorum profundus of the forearm, in that it acts as distally as the DIP joints of the toes.
- The flexor hallucis longus is analogous to the flexor pollicis longus, and flexes the big toe at the interphalangeal joint.
29
Q
tarsal tunnel
- what passes through?
- how can you get tarsal tunnel syndrome?
A
- “Tom Dick and A Very Nervous Harry”
- The tarsal tunnel is analogous to the carpal tunnel; its floor is the medial surface of the talus and calcaneus. Its roof is another flexor retinaculum.
- Through the tarsal tunnel pass the tendons of three of the muscles of the posterior compartment of the leg:
- Tibialis Posterior, flexor Digitorum longus, posterior tibial Artery and Vein, tibial Nerve, flexor Hallucis longus
-
Tarsal tunnel syndrome, though less common than carpal tunnel syndrome, can result from impingement of the tibial nerve in the tarsal tunnel.
- causes shooting pain into the plantar aspect of the foot, and weakness of some of the intrinsic muscles of the foot if severe.
30
Q
where are the main muscles for eversion of the leg?
A
- lateral leg compartment is the main player for eversion.
- The fibularis longus and brevis are innervated by the superficial fibular nerve and will both plantar flex and evert.
- The small fibularis tertius everts, but dorsiflexes and is innervated by the deep fibular nerve; it functionally bridges between the lateral and anterior leg compartments.
- All three muscles are supplied by the fibular artery
31
Q
review movements at knee joint
- flexion is mostly what nerve?
- extension is mostly what nerve?
A
32
Q
reveiw movements at ankle joint
- which nerves for plantar flexion, dorsiflexion, inversion, eversion?
A
33
Q
which muscle has 3 different functions?
A
Sartorius
- In anterior compartment of the thigh, innervated by Femoral nerve
- In addition to typical flexion at the hip, also laterally rotates hip, and flexes the knee
- longest muscle!
36
Q
A
Semitendinosus, Semimembranosus, Biceps femoris long head
(all these true hamstrings extend thigh at hip and flex leg at knee)
- the recuts femoris flexes thigh at the hip, and extends the leg at the knee (vastus medius, lateralis, intermedius help with that extension)
37
Q
- muscles for plantar flexion / eversion, innervation?
- muscles for dorsiflexion / inversion, innervation?
A
Any muscle in posterior leg versus anterior leg.
- gastrocnemius/ soleus (tibial nerve, plantar flexion) vs. tibialis anterior/ extensor hallucis longus/ extensor digitorum longus (deep fibular nerve, dorsiflexion)
- Tibialis anterior and posterior (ankle dorsiflexion, foot inversion – deep fibular) vs. Fibularis longus and brevis (plantar flexion, eversion - superficial fibular)
38
Q
- innervation of posterior leg muscles?
- distinguish tibialis posterior from tibialis anterior?
A
- all posterior leg muscles are innervated by tibial nerve
- both tibialis posterior and anterior invert the foot
- however:
- tibialis posterior is innervated by tibial nerve, also plantar flexes
- tibialis anterior is innervated by the deep fibular nerve, also dorsiflexes
Tibial nerve review:
Deep
- Popliteus – Laterally rotates the femur on the tibia to unlock the knee.
- Flexor Hallucis Longus – Flexes the big toe and plantar flexes the ankle.
- Flexor digitorum Longus – Flexes the other digits and plantar flexes the ankle.
- Tibialis Posterior – Inverts the foot and plantar flexes the ankle.
Superficial
- Plantaris – Plantar flexes the ankle.
- Soleus – Plantar flexes the ankle.
- Gastrocnemius – Plantar flexes the ankle and flexes the knee.
39
Q
1 most commonly injured ligament?
most common cause of ankle sprain?
where is the pain?
A
- usually caused by inversion of foot
- # 1 injury = AFTL - anterior talofibluar ligament
- #2 injury = CFL - calcaneofibular ligament
- # 3 injuy = PTFL - posterior talofibular ligament
- (strained in order of anterior to posterior)
- pain at lateral ankle, anterior to the malleolus (not on the bone)
