Week 3 Flashcards
main functions of lower limb
locomotion, supporting body weight, and maintaining balance.
gluteal region
area of lower limb attachment to axial skeleton; posterior to pelvic bones at proximal end of femur. bones include: pelvis and proximal end of femur (hip joint).
thigh
between hip and knee joint (femur)
leg
between the knee and ankle joints (tibia and fibula)
foot and digits (toes)
distal to ankle joint (tarsals, metatarsals, and phalanges)
Hip joint
between head of femur and cup-shaped acetabulum on lateral surface of pelvic bone. Multi-axial ball and socket joint designed for stability and weightbearing. flexion/extension, adduction/abduction, and external/internal rotation
ligaments that stabilize the hip joint
ligament of head of femur, iliofemoral ligament, pubofemoral ligament, ischiofemoral ligament
iliofemoral ligament
“y” shaped; continuous with anterior part of joint capsule; prevents hyperextension of the hip joint. It’s the strongest of hip ligments
pubofemoral ligament
triangular; continuous with anterior and inferior part of joint capsule; prevents excessive abduction and extension
ischiofemoral ligament
spiral shaped; continuous with posterior part of joint capsule; prevents hyperextension and helps hold head of femur in acetabulum
hip joint blood supply
primarily medial and lateral femoral circumflex arteries that anastamose around the neck of femur. medial provides majority of supply. damage to either can cause avascular necrosis of femoral head
knee joint
between condyles of distal femur and condyles of proximal tibia. allows for flexion and extension with a small degree of medial and lateral rotation
patellofemoral joint
between posterior aspect of patella with anterior aspect of distal femur
ligaments of knee
anterior/posterior cruciate ligaments, tibial (medial) and fibular (lateral) collateral ligaments
anterior cruciate ligament
attaches anterior aspect of tibia and posterior aspect of femur. Prevents anterior displacement of tibia on femur
posterior cruciate ligament
attaches posterior aspect of tibia and anterior aspect of femur. Prevents posterior displacement of tibia on femur
Tibial (medial) collateral ligament
Wide and flat on medial side of knee joint between medial epicondyles of femur and medial condyle of tibia
fibular (lateral) collateral ligament
thin and round on lateral side of knee joint between lateral epicondyle of femur and head of fibula
medial and lateral meniscus
c shaped fibrocartilaginous structures found in knee joint that deepen the articular surface of the tibia to increase stability of knee and function as shock absorbers
3 most commonly injured structures in knee
medial collateral ligament, medial meniscus, and anterior cruciate ligament. (Called “unhappy triad of O’Donohue” when injured together)
ankle joint
distal tibia and fibula with the talus of the foot. allows for dorsiflexion and planter flexion. Joint more stable when dorsiflexed than when plantar flexed
primary ligamentous support of ankle
broad deltoid ligament on medial side of ankle
3 ligaments on lateral side of ankle
anterior talofibular, posterior talofibular, and cancaneofibular
ankle sprains
normally occur via excessive inversion of a plantarflexed weight-bearing foot. Anterior talofibular ligament is most at risk of damage
subtalar joint
between inferior surface of talus and the superior surface of the calcaneous. allow for inversion and eversion of foot
muscles of gluteal region
abduct, extend, and externally rotate femur
superficial abductors and extensors of femur
gluteus maximus, gluteus medius, gluteus minimus and tensor fascia
gluteus maximus innervation
inferior gluteal nerve
gluteus medius innervation
superior gluteal nerve
gluteus minimus innervation
superior gluteal nerve
tensor fascia innervation
superior gluteal nerve
Deep external rotators of femur
external rotation and adduction. Piriformis, obturator internus, superior and inferior gamellus, and quadratus femoris
piriformis innervation
nerve to the piriformis
obturator internus innervation
nerve to the obturator internus
superior and inferior gamellus innervation
nerve to the obturator internus
quadratus femoris innervation
nerve to the quadratus femoris
blood supply of muscles in gluteal region
branches of inferior and superior gluteal arteries
compartments of thigh
anterior, posterior, and medial; separated by the intermuscular septa
anterior compartment of thigh
primarily extend the leg at the knee. Innervated by the femoral nerve and supplied by branches of the femoral and deep femoral arteries
medial compartment of thigh
primarily adduct the thigh at the hip. Innervated by the obturator nerve and supplied by branches of deep femoral and obturator arteries
posterior compartment of thigh
flex the leg at the knee and extend the thigh at the hip. Innervated by the sciatic nerve and supplied by the branches of the deep femoral artery
muscles of anterior compartment of the thigh
iliopsoas, sartorius, quadriceps
rectus femoris, vastus lateralis, vastus medialis, vastus intermedius
muscles of the medial compartment of the thigh
pectineus, adductor longus, adductor brevis, adductor magnus, gracilis, and obteratur externus
muscles of the posterior compartment of thigh
hamstrings
semitendinosus, semimebraneosus, biceps femoris
compartments of the leg
anterior, posterior, and lateral; separated by the intermuscular septa and bones
anterior compartment of leg
dorsiflex and invert the foot and extend the toes. innervated by the deep fibular nerve and supplied by branches of the anterior tibial artery
lateral compartment of leg
primarily plantar flex and evert the foot. innervated by superficial fibular nerve and supplied by branches of the fibular artery
posterior compartment of leg
plantarflex and invert the foot and flex the toes. innervated by the tibial nerve and supplied by branches of the posterior tibial artery
muscles of the anterior compartment of leg
tibialis anterior, extensor hallucis longus and extensor digitorum longus
muscles of the posterior compartment of leg
gastrocnemius, soleus, plantaris, popliteus, flexor haluucis longus, flexor digitorum longus, tibialis posterior
muscles of the lateral compartment of leg
fibularis longus and fibularis brevis
lumbar plexus
somatic plexus formed by anterior rami of spinal nerves L1-L4. Major nerves derived from lumbar plexus are lateral cutaneous nerve of thigh (L2, L3), femoral nerve (L2-L4) and obturator nerve (L2-L4)
Sacral plexus
somatic plexus formed by anterior rami of spinal nerves S1-S4. Major nerves are superior gluteal (L4-S1), inferior gluteal nerve (L5-S2), sciatic nerve (L4-S3), posterior femoral cutaneous (S1-S3), and the named branches to the small external rotators
femoral nerve lesion
deficits in flexion of thigh at the hip and extension of the knee. Loss of sensation on the anterior thigh and the medial knee, leg, and foot
obturator nerve lesion
deficits in adduction and external rotation of thigh at the hip. Loss of sensation in a defined area of the medial thigh above the knee
superior gluteal nerve lesion
deficits in abduction of the thigh at the hip (or lateral flexion of the trunk on a fixed limb). Hip drops when foot on the uninjured side is raised and patient shifts weight of trunk to injured side. N to maintain center of gravity (trendelenburg gait) O sensory deficits
tibial nerve lesion
deficits of inversion of the foot, plantarflexion of the ankle and flexion of the toes. Loss of sensation on the posterolateral leg to the lateral malleolus, the sole of the foot, and lateral side of the foot.
superficial fibular nerve
deficits in eversion and plantarflexion of the foot. Loss of sensation over the lateral leg and dorsum of the foot
Deep fibular nerve
deficits of inversion of the foot, dorsiflexion of the foot, and extension of the toes. Loss of sensation in a triangular area of skin between 1st and 2nd toes
femoral artery
main artery of lower limb; a continuation of the external iliac artery starting as it crosses under the inguinal ligament and enters the femoral triange
profunda femoris artery
arises off the posterolateral aspect of the femoral artery in the femoral triangle. It then travels poteriorly and distally; gives off 3 main branches
3 branches of profunda femoris artery
perforating branches, lateral femoral circumflex artery, and medial femoral circumflex artery
perforating branches of profunda femoris artery
3 or 4 arteries that perforate the adductor magnus and contribute to the supply of the muscles in the posterior and medial thigh
lateral femoral circumflex artery
wraps around the anterior, lateral side of femur, supplying some muscles on the lateral aspect of thigh. It sends an important branch inferiorly to participate in the collateral circulation around the knee by anastamosing with the genicular arteries
medial femoral circumflex artery
wraps around the posterior side of the femur, supplying its neck and head.
adductor canal
a tunnel in the anterior superficial thigh, through which the femoral artery travels
popliteal artery begins
femoral artery moves through the end of the adductor canal through an opening in the adductor magnus called the adductor hiatus and enters the posterior compartment of the thigh, proximal to the knee. This is where it becomes called the popliteal artery
popliteal artery descends
down the posterior thigh, giving rise to genicular branches that supply knee joint. At lower border of popliteal fossa, the artery terminates by dividing into the anterior tibial and posterior tibial arteries
posterior tibial aretery
a division of the popliteal artery; gives a small branch to the lateral part of the leg, called the fibular (peroneal) artery and continues to the sole of the foot behind the medial malleoulus
anterior tibial artery
a division of the popliteal artery passes anteriorly between tibia and fibula through a gap in the interosseous membrane. Then it runs down the entire length of the leg into the foot, where it becomes the dorsalis pedis artery
superior and inferior gluteal arteries
supply the gluteal region. They arise from the internal iliac artery and enter the gluteal region via the greater sciatic foramen
2 major phases of the human gait cycle
stance phase (60%) and swing phase (40%)
stance phase of gait cycle
heel strike, foot flat, mid stance, heel off
swing phase of gait cycle
toe off, mid swing, heel strike
muscle movements of stance phase
hip progresses from flexion to extension; knee progresses from extension to slight flexion; ankle progresses from dorsiflexion to plantarflexion
muscle movements of the swing phase
hip progresses from extension to flexion; knee progress from flexion to extension; ankle progresses from plantarflexion to dorsiflexion
compartment syndrome in the leg
common in leg because of the very tight crural fascia; essential clinical feature: conscious patients in severe pain out of proportion to the injury, aggravated by passive muscle stretch; treated most reliably with open fasciotomy by incision of the skin and fascia.
what is compartment syndrome
occurs when pressure within an unyielding osteofascial compartment increases within that space. Irreversible muscle and nerve damage may occur within hours
cause of compartment syndrome
trauma, revascularization procedures, burns, and over-exercise
patellar apprehension test
positive test implies a preceding episode of patellar instability (subluxation or dislocation)
patellofemoral grind test
Patellofemoral pathology
Valgus stress test
MCL injury
Varus stress test
LCL injury
Lachman test
ACL injury
Anterior Drawer Test
ACL injury
Posterior drawer test
PCL injury
Tests for Medial and lateral meniscus
most sensitive test is pain with full flexion; also check joint line tenderness
Autonomic nervous system (ANS)
supplies internal organs and controls involuntary responses to changes in the internal and external environment. Divided into sympathetic division and the parasympathetic division
origin of preganglionic neurons in sympathetic nervous system
spinal cord levels T1-L2
preganglionic neuron length in sympathetic nervous system
short
postganglionic neuron length in sympathetic nervous system
long
location of ganglion in sympathetic nervous system
far from target organ; usually in sympathetic trunk
preganglionic neurotransmitter in sympathetic nervous system
acetylcholin
postganglionic neurotransmitter in sympathetic nervous system
norepinephrine
origin of preganglionic neurons in parasympathetic nervous system
spinal cord levels S2-S4 and Cranial nerve III, VII, IX and X nuclei in the brain
preglangionic neuron length in parasympathetic nervous system
long
postganglionic neuron length in parasympathetic nervous system
short
location of ganglion in parasympathetic nervous system
close to or in wall of target organ
preganglionic neuotransmitter in parasympathetic nervous system
acetylcholine
postganglionic neurotransmitter in parasympathetic nervous system
acetylcholine
Effects of sympathetic nervous system in gastrointestinal system
decrease motility and secretion, contraction of sphincters
Effects of sympathetic nervous system in bladder (urinary)
relaxation (inhibits voiding)
Effects of sympathetic nervous system in eyes
dilate pupil
Effects of sympathetic nervous system in skin
constricts blood vessels, stimulates sweat production; contraction of erector pili
Effects of sympathetic nervous system in liver and gallbladder
stimulates glucose production and release by liver; stimulates glycogen breakdown
Effects of parasympathetic nervous system in gastrointestinal system
increase motility and secretion, relaxation of sphincters
Effects of parasympathetic nervous system in bladder (urinary)
contraction (promotes voiding)
Effects of parasympathetic nervous system in eyes
constricts pupils
Effects of parasympathetic nervous system in skin
no effect
Effects of parasympathetic nervous system in liver and gallbladder
stimulates glycogen synthesis and storage; stimulates bile release from gallbladder
Effects of parasympathetic nervous system in reproductive system
erection
Effects of parasympathetic nervous system in respiratory system
bronchoconstriction and increased secretion
Effects of parasympathetic nervous system in cardiovascular system
decrease heart rate and force of contraction
Effects of parasympathetic nervous system in peripheral blood vessels
no effect
Effects of sympathetic nervous system in reproductive system
ejaculation
Effects of sympathetic nervous system in respiratory system
bronchodilation and reduced secretion
Effects of sympathetic nervous system in cardiovascular system
increase heart rate and force of contraction
Effects of sympathetic nervous system in peripheral blood vessels
vasoconstriction
Intermediolateral (IML)
call column in spinal cord grey matter that contain sthe cell bodies of the preganglionic sympathetic neurons
sympathetics to the skin of extremities and body wall
originate in the IML of spinal cord. Axons of preganglionic neurons exit the spinal cord via the ventral root of T1-L2 spinal nerves. (ie arterial blood vessels, errector pili muscles associated with hairs of skin and sweat glands)
sypathetics to the head
originate in the IML of the spinal cords. Axons exit via ventral root of upper thoracic spinal nerves. (ie iris of eye, arterial blood vessels in head, erector pili in head)
sympathetics tot he organs of the thorax
originate in IML of spinal cord. Axons exit via ventral root of T1-T5 spinal nerves. (heart, lungs, trachea, larynx, blood vessels)
sympathetics to the organs of the abdomen and pelvis
originate in IML of spinal cord. Axons exit via ventral root of T5-L1 spinal nerves. They are splanchnic nerves, which synapse in peripheral ganglia located around abdominal aorta and ganglia in the pelvis
Cranial outflow
parasympathetic nervous system. Cell bodies for cranial outflow are found in the brainstem nuclei of cranial nerves III, VII, IX, and X.
Sacral outflow
parasympathetic nervous system. Cell bodies for sacral outflow are located in IML of sacral spinal cord (S2-S4). Axons exit the spinal cord via ventral root of S2-S4 and travel to target organs via pelvic splanchnic nerves
Sympathetic system
Fight or flight
Parasympathetic system
Rest and digest
muscle contraction
energy from hydrolysis of ATP is transformed into mechanical energy during contraction
Epimysium
dense connective tissue that surrounds the entire muscle and is synonymous with the deep fascia
Perimysium
connective tissue that surrounds a group of fibers to form a fascicle. It conveys the large blood vessels and nerves into the muscle
Type II skeletal muscle fibers
better for short bursts of speed; fatigue more quickly. Have hight ATPase activity. ATP is generated by anaerobic glycolysis and cells contain high levels of glycogen. Speed of contraction is high and there are small motor units in the muscle
Type I skeletal muscle fibers
contain large amounts of myoglobin and mitochondria. Low ATPase activity (appear light in ATPase-stained section)
More efficient over long periods of time; used when sustained production of force is required; mainly for postural maintenance of endurance exercise.
ATP generated by oxidative phosphorylation, speed of contraction is low, and there are large motor units in the muscle
Type II skeletal muscle fibers
better for short bursts of speed; fatigue more quickly. Have hight ATPase activity. ATP is generated by anerobic glycolysis and cells contain high levels of glycogen. Speed of contraction is high and there are small motor units in the muscle
sarcolemma
plasma membrane of muscle cells
sarcoplasmic reticulum
internal membrane network that has no connection with the extracellular space. Forms triads with T-tubules. It is where intracellular calcium is stored and release for muscle contraction
myofibrils
take up about 80% of cytoplasm in muscle cells. They are composed of 2 major filaments formed by contractile proteins: thin actin filaments and thick myosin filaments
desmin
intermediate filament protein found in muscle cytoplasm. Anchored inside sarcolemma and extends from one myofibril to another. helps organize cytoplasm and facilitates coordinated contraction of myofibrils
sarcomeres
organized repeating contractile elements of myofibrils.
z-line
defines boundary of sarcomere; contains actin binding protein, alpha actinin
I-band
composed exclusively of actin thin filaments; width decreases in contraction
A-band
composed of overlapping thick and thin filaments; width is constant in contraction
M-line
middle of H-band; overlapping tails of thick filaments
motor end plate
neuromuscular junction; each skeletal muscle fiber is innervated by an axon of a motor neuron. the axon interacts with the muscle fibers via the motor end plate
contraction begins
with release of acetylcholine from synaptic vesicles in motor neuron end plate, which binds to sarcolemma and causes depolarization
motor end plate
neuromuscular juntion; each skeletal muscle fiber is innervated by an axon of a motor neuron. the axon interacts with the muscle fibers via the motor end plate
contraction begins
with release of acetylchonine from synaptic vesicles in motor neuron end plate, which binds to sarcolemma and causes depolarization
muscle spindle
sensory organ in skeletal muscle.
