Download Anatomy Exam 5 Lecture 28-Anterior and Medial Thigh Thigh Fascia

Anatomy Exam 5
Lecture 28-Anterior and Medial Thigh
 Thigh Fascia, consists of two layers (superficial and deep)
o Superficial is deep to dermis, and contains cutaneous nerves and
veins.
 Great (long) saphenous vein located in superficial fascia.
o Longest vein in body, ascends from foot to groin. Located anterior to
medial malleolus and posterior to medial femoral condyle.
o Saphenous nerve accompanies vein, which is a branch of the femoral
nerve.
o Long Saphenous vein joins the femoral vein, by entering the deep
fascia through the saphenous opening.
o Can be used for coronary artery bypass surgery, saphenous cutdown
is made anterior to the medial malleolus.
 Pt’s may complain of pain along medial border of foot due to a
lesion of the saphenous nerve after surgery.
 The Femoral vein and arteries both can be catheterized to access the heart.
o The femoral vein goes directly to the right atrium of the heart.
o The femoral artery goes directly to the left atrium of the heart.
 Lumbar Plexus is made of L1-L4 ventral rami, which are formed in the psoas
major.
o The two largest and most important branches are the:
 Obturator nerve (L2-L4)
 Femoral nerve (L2-L4)
 Sacral plexus is located on posterior wall of lesser pelvis.
o Consists of lumbosacral trunk (L4-L5) and S1-S4 ventral rami
o Two main nerves of sacral plexus
 Sciatic nerve-divides into tibial and fibular nerves.
 Pudendal nerve
 Lateral femoral cutaneous nerve (L2 and L3) passes deep to inguinal
ligament to enter thigh. Innervates the lateral aspect of the thigh.
 Deep Fascia of the Thigh
o Known as fascia lata.
o Contains saphenous opening, where saphenous vein passes through
to join with femoral vein.
o Deep fascia of the leg is called the crural fascia.
o Thickens laterally to form the iliotibial tract or band.
 Runs from iliac tubercle to “Gerdy’s tubercle” which is located
on the lateral tibial condyle.
o Know tibial tuberosity as a bony landmark!
o Deep fascia divides the thigh into three compartments and inserts into
the linea aspera of the femur.
 Medial-adductors innervated by obturator n.
 Anterior-knee extension, innervated by femoral n.
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 Posterior-knee flexion, innervated by sciatic n.
Anterior Thigh Muscles:
o Iliopsoas muscle:
 Chief flexor of the thigh
 Located deep and medial to sartorus m, and underlies femoral
nerve.
 Made of two muscles, iliacus and psoas major
 Inserts into lesser trochanter
o Sartorius muscle:
 Longest muscle, most superficial anterior muscle
 Originates at ASIS
 Flexes, abducts, and laterally rotates thigh
 Innervated by femoral nerve (L2-L4)
o Quadriceps Femoris muscle:
 Four heads
 Rectus femoris
o Only head to cross hip joint, flexes at hip.
o Origin is anterior inferior iliac spine (AIIS)
 Vastus lateralis
 Vastus medialis
 Vastus intermedius-lies deep to rectus femoris
 Tendons of all 4 heads unite to form quadriceps tendon, which
continues inferiorly as ligamentum patella (patellar ligament).
 Acts as chief extensor of the leg.
 Inserts onto tibial tuberosity.
 Osgood-Schlatter disease is an irritation of the patellar
tendon at the tibial tuberosity.
o Occurs in active boys and girls aged 9-16,
coinciding with periods of growth spurts.
o More frequent in boys than girls.
o Tx is RICE and ibuprofen or acetaminophen
o Sx resolve within a few months
Medial Thigh Muscles:
o Pectineus muscle:
 Innervated by femoral nerve.
 Adducts and flexes thigh
 Located deep to femoral artery and nerve in femoral triangle.
o Adductor Longus muscle:
 Forms the medial aspect of the femoral triangle.
 Adducts thigh
 Innervated by obturator nerve.
o Gracilis muscle:
 Only adductor to cross knee joint.
 Insertion is superior part of medial surface of tibia
 Adducts thigh and flexes and medially rotates leg
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 Located medial to adductor longus
o Adductor Brevis muscle:
 Lies deep to pectineus and adductor longus
 Adducts thigh, and limited thigh flexion.
 Innervated by anterior obturator nerve.
 Anterior obturator nerve division lies on top of
adductor brevis
 Posterior obturator nerve division goes deep to
adductor brevis
 Groin pull occurs through strain, stretch and possible tearing of
proximal attachments of thigh adductor and flexor muscles.
o Adductor Magnus muscle:
 Largest adductor muscle
 Superior part lies deep to adductor brevis
 Has two parts:
 Adductor portion (pubofemoral portion)
o Origin-ischiopubic ramus
o Innervation-obturator nerve
o Action-adducts and flexes thigh
 Hamstring portion (ischiocondylar portion)
o Origin-ischial tuberosity
o Insertion-adductor tubercle (medial epicondyle)
o Innervation-tibial division of sciatic nerve
o Action-adducts and extends thigh
o Obturator Externus
 Lies deep to pectineus and covers obturator foramen
 Innervated by obturator nerve
 Anterior branch passes in front of muscle
 Posterior branch pierces muscle
 Laterally rotates femur
Femoral Triangle
o Boundaries:
 Floor-pectineus and iliopsoas
 Roof-fascia lata
 Lateral-sartorius
 Medial-adductor longus
o Contains the following from lateralmedial
 NAVaL: femoral nerve, femoral artery, femoral vein, and
inguinal lymph nodes.
o Femoral Artery
 AortaCommon Iliac arteryExternal Iliac arteryFemoral
artery
 Chief arterial supply to lower limb
 Biggest branch is profunda femoris artery
 Inferiorly it gives rise to the descending genicular artery
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o At the apex of the femoral triangle the arrangement of the femoral
neurovascular bundle goes from side by side, to rotating making it
anterior to posterior.
 Order is then from anteriorposterior: femoral artery,
femoral vein, profunda femoris artery, and profunda femoris
vein.
 Profunda femoris artery gives rise to medial and lateral
circumflex femoral arteries. Lateral circumflex goes deep to
quad towards the lateral thigh and femoral head.
 Profunda femoris artery goes superior to pectineus and deep
to adductor longus.
 Gives rise to three or four perforating arteries that
participate in cruciate anastomoses.
o Femoral Circumflex arteries
 Medial circumflex femoral artery-main supply to femoral head
and neck, passes between iliopsoas and pectineus to reach
posterior thigh.
 Lateral circumflex femoral artery-passes laterally and deep to
Sartorius and rectus femoris. Supplies lateral thigh and
femoral head. Three branches: ascending, descending, and
transverse.
Cruciate Anastomoses
o Collateral circulation around hip joint, involves these arteries:
 Inferior gluteal artery
 First perforating artery
 Medial femoral circumflex artery
 Lateral femoral circumflex artery
o Can ligate femoral artery in emergency situations, without risk of total
blood loss to lower limb.
Femoral Nerve (L2-L4)
o Largest branch of lumbar plexus.
o Supplies anterior thigh muscles, and hip and knee joints
 Iliacus
 Sartorius
 Quadriceps femoris
 Tensor fasciae latae
o Terminal cutaneous branch is saphenous nerve, which accompanies
the long saphenous vein.
 Becomes superficial between Sartorius and gracilis.
 Supplies anterior and medial knee and leg
Femoral sheath
o Funnel-shaped fascial tube that allows femoral vessels to glide
smoothly beneath the inguinal ligament during hip movement.
o Doesn’t contain femoral nerve.
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Femoral hernia can occur in femoral ring. This is a weak area in abd wall
where a loop of intestine can protrude into femoral canal.
Adductor canal-intermuscular passage that contains femoral vessels, begins
at femoral triangle apex and ends at adductor hiatus.
Adductor hiatus-opening in tendon of adductor magnus, allows femoral
vessels to reach popliteal fossa.
Knee Joint Injuries
o Most common injuries are ligament sprains in contact sports.
o Tibial and fibular collateral ligaments are tightly stretched when leg is
extended. Normally prevent disruption of sides of knee joint.
 Injury to TCL and medial meniscus is frequently caused by a
blow to lateral side of extended knee. Or by excessive lateral
twisting of flexed knees while running.
o ACL-serves as pivot for rotatory movements of the knee and is taut
during flexion
 May tear due to rupture of TCL, creating an unhappy triad of
knee injuries.
o Hyperextension and severe force directed anteriorly against femur
with knee semi-flexed may tear the ACL.
 Injury causes free tibia to slide anteriorly under fixed femur
 ACL may tear away from the femur or tibia, known as anterior
drawer sign.
o PCL ruptures occur when a player lands on the tibial tuberosity with
the knee flexed.
 Usually occur in conjunction with tibial or fibular ligament
tears
 Injury allows tibia to slide posteriorly under the fixed femur,
known as posterior drawer sign.
Lecture 29-Posterior Leg and Plantar Foot
 Anatomical leg is the part of the lower limb between the knee and ankle
joints.
o Tibia is the dominant weight-bearing bone.
o Fibula is subordinate, it’s role is in muscle attachment.
o Tibia and fibula are joined in two ways
 Tibiofibular joint-synovial joint (where the head of the fibula
joins the tibia).
 Tibiofibular syndesmosis-fibrous joint that includes
interosseous membrane.
 These fibers resist downward muscular pull on fibula
by the 8 muscles that attach and pull down.
 These joints permit the malleoli to separate slightly, so during
dorsiflexion the wide anterior part of the trochlea can wedge
itself between the malleoli creating stability.
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Leg made of three muscular compartments formed by fascial septa
(Posterior, Lateral and Anterior), this forms closed spaces ending at the
joints. The fascia of the leg is very strong and unyielding, which is why
compartment syndrome occurs frequently in the leg.
Posterior-separated from the other compartments by the interosseous
membrane and the posterior intermuscular septum.
o The muscles in the posterior compartment plantarflex the foot and
toes and invert the foot.
o Muscles in the posterior compartment are important for locomotion,
to allow propulsion, i.e. kicking off from a surface with plantar flexors.
o Superficial Muscles-form the prominence of the calf.
 Gastrocnemius
 Origin:
o Lateral headlateral condyle of femur
o Medial headpopliteal surface and femur
 Insertion: Calcaneal (Achilles) tendon
 Nerve: Tibial nerve
 Action: Flexion of knee and plantarflexion of foot.
 Soleus-work horse of plantarflexion, in a seated position only
the soleus is active.
 O: Tibia and fibular head and neck, interosseous
membrane
 I: Calcaneal tendon
 N: Tibial nerve
 A: Plantarflexion of foot and stabilizes leg
 Plantaris-absent in 5-10% of population, similar to palmaris
longus.
 O: lateral supracondylar line
 I: Calaneal tendon
 N: Tibial nerve
 A: Week plantarflexion of foot
o Deep muscles-accounts for less than 7% of total force of
plantarflexion, because the tendons are too close to the ankle joint.
 Alone (as in a tendon rupture) these muscles cannot raise the
body. In the absence of plantarflexion a less effective push-off
can be performed from the midfoot.
 Both flexor hallucis longus and flexor digitorum longus are
important in ‘toe-off’ action that completes the action of the
superficial muscles, creating walking stride.
 Flexor hallucis longus
 O: Inferior fibula and interosseous membrane
 I: Distal phalanx of of 1st metatarsal
 N: Tibial nerve
 A: Flexes toe and week plantarflexion
 Flexor digitorum longus
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 O: Inferior to soleal line
 I: Distal phalanges of metatarsals 2-5
 N: Tibial nerve
 A: Flexes phalanges 2-5 and plantarflexion
 Tibialis posterior-main invertor muscle of the leg, also
supports arch of the foot, and initiate elevation of the heel.
 O: Interosseous membrane and tibia + fibula
 I: 2-4 metatarsals, navicular, cuneiform, cuboid and
calcaneous
 N: Tibial nerve
 A: Plantarflexion and inversion.
 Popliteus
 O: Lateral condyle of femur
 I: Superior to soleal line
 N: Tibial nerve
 A: Rotates femur on fixed tibia and vice versa
o Blood supply to the posterior compartment is provided by the
posterior tibial artery (larger terminal branch of popliteal artery).
THE FOOT
Two surfaces of the foot: dorsal and plantar.
o Skin and fascia generally stronger on the plantar surface because of
grip, weight-bearing, abrasion, etc.
o Dorsum is thinner, less sensitive skin. Swelling usually occurs on
dorsal side. Contains thin deep fascia.
o The sole is thick, highly vascularized, sensitive skin. Contains strong,
fibrous subcutaneous tissue. Deep fascia is called plantar fascia, thick
central part is called plantar aponeurosis.
o Plantar aponeurosis arises proximally from the calcaneal tuberosity,
and distally becomes continuous with flexor tendons of the toes.
 Provides protection to underlying structures, maintains the
arch and serves as attachment for skin.
30 joints in the foot with 26 bones, classified according to articulating bones:
o Intertarsal joints, Tarsometatarsal joints, Intermetatarsal joints,
Metatarsophalangeal joints, and interphalangeal joints.
o Two main actions occurring at the foot joints
 Eversion/inversion of the foot
 Flexion/extension of the toes
o Joints are otherwise involved in spreading of the foot to absorb shock.
Eversion/Inversion occurs at
o Intertarsal joints-two important joints
 Subtalar joint-synovial articulation between talus and
calcaneus where talus rests on calcaneous.
 Transverse tarsal joint-two separate joints aligned
transversely: talonavicular joint and calcaneocuboid joint
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At this joint the midfoot and forefoot rotate on hindfoot
as a unit. Greatest amount of foot movement occurs
here.
o Tarsometatarsal joints.
 Permit some rotation and some flexion/extension. Important
to adapt to uneven surfaces.
Flexion/Extension occurs at
o Metatarsophalangeal joints-also produce abduction and adduction.
o Interphalangeal joints
Foot Ligaments
o Plantar aspect-all three involved in supporting the longitudinal arch
of the foot
 Plantar calcaneonavicular (spring ligament)
 Long plantar
 Plantar calcaneocuboid (short plantar)
o Forefoot-the bones of the metatarsophalangeal and interphalangeal
joints are united by two main types of ligaments
 Collateral ligaments
 Deep transverse metatarsal ligaments
Foot Nerves
o Motor and Sensory: Tibial and Deep Fibular
o Sensory: Superficial fibular, Saphenous and Sural
Arteries of the Foot
o Anterior tibial arterydorsalis pedis
o Posterior tibial arteryplantar arteries
Foot Muscles
o All intrinsic muscles of the foot originate and insert in the foot. Two
main categories (dorsal extensors and plantar flexors), overall
purpose is to support the arches and assist the long muscles during
locomotion.
o Dorsal extensors (2)
o Plantar flexors (18)-under the bony arch between heel and toes, and
organized into 4 layers.
 Layer 1-all originate on calcaneal tuberosity and extend to
phalanges.
 Flexor digitorum brevis
o O: Calcaneal tuberosity
o I: Proximal 1st phalanx
o N: Medial plantar nerve
o A: Flexes digitis 2-5
 Abductor hallucis
o O: Calcaneal tuberosity
o I: Proximal 1st phalanx
o N: Medial plantar nerve
o A: Abducts/flexes big toe
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Abductor digiti minimi
o O: Calcaneal tuberosity
o I: Proximal 5th phalanx
o N: Lateral plantar nerve
o A: Abducts/flexes 5th phalanx
Layer Two
 Quadratus plantae
o O: Calcaneus
o I: Tendon of FDL
o N: Lateral plantar nerve
o A: Assists FDL w/flexing
 Lumbricals
o O: FDL tendons
o I: Expansion at 2-5th phalanges
o Innervation:
 2nd lumbrical- Medial plantar nerve
 3rd-5th lumbricals-Lateral plantar nerve
o A: Flexes proximal and extends middle and distal
phalanges
Layer Three
 Adductor hallucis
o Origin:
 Oblique head-metatarsals 2-4
 Transverse head-plantar ligament of MTP
joint
o I: Proximal 1st phalanx
o N: Lateral plantar nerve
o A: Adducts/Flexes big toe
 Flexor digiti minimi brevis
o O: 5th metatarsal
o I: 5th proximal phalanx
o N: Lateral plantar nerve
o A: Flexes 5th phalanx
 Flexor hallucis brevis
o O: Cuboid and Lateral cuneiform
o I: Both sides of proximal 1st phalanx
o N: Medial plantar nerve
o A: Flexes big toe
Layer Four
 Plantar interossei (3)
o O: Metatarsals 3-5 (medial)
o I: Phalanges 3-5 (medial)
o N: Lateral plantar nerve
o A: Adducts and flexes
 Dorsal interossei (4)
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O: Inbetween metatarsals 1-5
I: Medial and lateral proximal phalanxes
N: Lateral plantar nerve
A: Abducts digits 2-4 and flexes
Lecture 31-Anterolateral Leg and Dorsal Foot
 ANTERIOR LEG
 The anterior compartment of the leg is located just lateral to the sharp
medial border of the tibia.
 Retinacula: at the inferior end of the anterior compartment are two band-like
thickenings of the deep (crural) fascia: superior extensor retinaculum and
inferior extensor retinaculum.
o Function is to bind tendons of the anterior compartment, prevents
anterior bowstringing during dorsiflexion.
 Muscles of the anterior compartment dorsiflex at the ankle and extend the
toes. Dorsiflexion has a range of 20-30 degrees from neutral, and 25% the
strength of plantarflexion
o The muscles of dorsiflexion play critical roles in walking and
balancing while standing.
o In gait help with smooth lowering of foot after heel strike contact, and
toe-ground clearance when the foot is in swing.
o Tibialis anterior-most medial and superficial dorsiflexor, tendon can
be palpated lateral to tibia at ankle.
 O: Lateral condyle of tibia
 I: Medial cuneiform and 1st metatarsal
 N: Deep fibular nerve
 A: Dorsiflexion and inversion
o Extensor digitorum longus-each tendon forms an extensor expansion
which divides and has a central band that inserts on the base of the
middle phalanx; and two lateral bands that insert on the base of distal
phalanx.
 O: Lateral condyle of tibia and superior fibula, and
interosseous membrane
 I: Middle and Distal 2nd-5th phalanges
 N: Deep fibular nerve
 A: Dorsiflexion and extends 2nd-5th phalanges
o Extensor hallucis longus-lies deep between Tibialis anterior and EDL.
 O: Middle fibula and interosseous membrane
 I: Distal phalanx of great toe
 N: Deep fibular nerve
 A: Dorsiflexion and extension of 1st phalanx.
o Fibularis tertius-separated part of EDL.
 O: Inferior fibula and interosseous membrane
 I: 5th metatarsal
 N: Deep fibular nerve
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 A: Dorsiflexion and aids with eversion.
The small anterior compartment is especially prone to compartment
syndrome.
o Shin splints are a mild form of anterior compartment syndrome.
Caused by repetitive microtrauma to Tibialis anterior. Usually occurs
following sudden overuse, i.e. walkathon. Treatment is rest and
strengthening.
Deep fibular nerve is located deep between Tibialis anterior and EDL and
EHL.
The anterior tibial artery supplies the structures in the anterior
compartment; it is the smaller terminal branch of the popliteal artery. Begins
at inferior border of Popliteus.
LATERAL LEG
The lateral compartment is the smallest of the leg. Contains muscles that
evert the foot, and some weak plantarflexion.
Muscles of Lateral leg-consists of two muscles. Both tendons pass through
the superior and inferior fibular retinacula, which provides leverage for
plantarflexion.
o Fibularis longus-longer and more superficial than brevis.
 O: Head and superior fibula
 I: 1st metatarsal and medial cuneiform
 N: Superfical fibular nerve
 A: Everts foot and weak plantarflexion
o Fibularis brevis
 O: Inferior fibula
 I: 5th metatarsal
 N: Superficial fibular nerve
 A: Everts foot and weak plantarflexion
Eversion of the foot is necessary for holding down medial margin of the foot
during toe-off, and prevents excessive inversion, which could lead to injury.
Human foot is unique through eversion, which places more emphasis on
medial foot…most primates walk on lateral foot.
Blood supply to the lateral compartment comes from perforating arteries
from fibular and anterior tibial arteries.
The common fibular nerve is the most often injured nerve in the lower limb
due to it’s superficial location. Fx of the fibular neck or knee may sever this
nerve.
o A severed fibular nerve causes footdrop and results in flaccid
paralysis of the anterior and lateral compartment muscles. No
dorsiflexion or eversion.
DORSAL FOOT
Two closely connected muscles on dorsum of foot.
o Extensor digitorum brevis-aids extensor digitorum longus
 O: Calcaneous
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 I: Extensor tendons (2-4)
 N: Deep fibular nerve
 A: Aids EDL
o Extensor hallucis brevis-aids extensor hallucis longus
 O: Calcaneous
 I: Proximal 1st phalanx
 N: Deep fibular nerve
 A: Aids EHL
Blood supply comes from Dorsalis pedis artery, it is a direct continuation of
the anterior tibial artery. Begins at the level of the malleoli.
o Dorsalis pedis branches into the following:
 Arcuate arterysupplies the toes
 Lateral tarsal arteryanastomoses with arcuate artery
 Deep plantar arteryanastomoses with deep plantar arch
o Pedal pulses obtained at dorsalis pedis artery, diminished pulse may
indicate peripheral artery disease or vascular injury.