L7 Anterior Thigh, Anterior And Lateral Leg, Foot Flashcards
Anterior compartment of the thigh
Femoral n.
Main actions: extension of knee, a little hip flexion
Anterior thigh muscles
Quadriceps: Rectus femoris Vastus lateralis Vastus medialis Vastus intermedialis
Not quads
Iliopsoas
Pectineus
Sartorius
All innervated by femoral n.
Quadriceps
Vastus lateralis
Insert on tibia via quadriceps tendon Origin on femur
A: extends knee
Vastus medialis
Same origin/insertion
A: extends leg at knee
Rectus femoris
Origin on anteriorinferior iliac spine
Same insertion
A: extends leg, flexes thigh
Femoral triangle
Describe how femoral n comes from pelvis into LE
Inguinal ligament is above triangle
Three muscles form the borders
Iliopsoas flexes thigh
Pectineus adducts and flexes thigh
Sartorius flexes, abducts, laterally rotates thigh and flexes leg
Femoral nerve
L2-L4
Divides into serval terminal branches
Somatic efferent = muscles to anterior thigh
Terminates as a peripheral cutaneous nerve- somatic afferent= anterior and medial portion of leg
Test function of femoral n- tap medial and anterior portion of leg or ask to flex thigh and extend knee
Patellar reflex (L2-L4)
Testing L2-l4 spinal cord segments but really femoral n
Sensory info goes back through anterior ramus
Cruciate ligament
Prevents forward movement of tibia relative to femur due to force from walking
Cross fingers middle over index, put hand on knee, anterior =middle finger..posterior= index finger
ACL keeps knee functional Prevents forward movement of tibia relative to femur due to force from walking. Ruptured = tibia can be forward “anterior draw sign”
PCL often not torn
Most common knee injury
Lateral force applied against knee when foot fixed on ground and cannot move
ACL, MCL, and medial meniscus are likely torn
Anterior thigh in locomotion
Knee extensors stabilizes knee during stance phase
Rectus femoris decelerates thigh to prepare for swing phase
Hip flexors , iliopsoas, accelerate thigh during swing phase
Medial compartment of the thigh
Obturator n
Main actions: adductors of hip
Medial compartment muscles
Adductor longus Adducts thigh Adductor brevis Adducts thigh Gracilis Adducts thigh Adductor magnus Adducts thigh
Adductor magnus
Has adductor and hamstring part
Seen in anterior: iscilia tuberosity origin
Tibial n
Extend thigh, adducts thigh
Seen posterior:
Obturator n
Adductor
Obturator n
Nerve to medial compartment
Enters through obturator foramen
Cutaneous sensation to the medial thigh
Divides into anterior and posterior branches around the adductor brevis
Medial thigh role in locomotion
Doesn’t have role
People with strong adduction muscles can dislocate hip due to pull of excessive tone of adductors
Fix by blocking obturator n.
Anterior compartment of leg
Deep fibular n.
Main actions: dorsi flexion, inversion foot, extension toes
Anterior leg muscles
Tibialis anterior
A: dorsi flexion and inversion
Extensor hallucis longus
A: extends big toe, dorsiflexes foot
Extensor digitorum
A: extends lateral 4 digits, dorsiflexes foot
Deep fibular n
Divides into deep and superficial fibular nerves around neck of fibula
Deep fibular n travels between tibialis anterior and extensor digitorum longus
Motor innervation to anterior compartment
Sensory info from web space btw hallux and 2nd toe
Common fibular n
Separates from tibial n in inferior 1/3 of thigh
Anterior leg in locomotion.
Dorsiflexors help lower foot to ground by decelerating foot fall
Dorsiflexors cleat foot during swing phase
Lateral compartment of leg
Superficial fibular n.
Foot eversion
Lateral leg muscles
Fibularis longus
Fibularis brevis
Evert foots
Superficial fibular n
Divides into deep and superficial fibular nerves around neck of fibula
Terminal branch of the common fibular n
Motor innervation to lateral compartment of leg
Sensory info from anterolateral leg and most of dorsum of foot
Lateral leg in locomotion
Foot everters (and inventors) are active when on uneven ground
Compartment syndrome
Increased intracompartmental pressure
Decreased venous and lymphatic drainage
Deep crural fascia is really strong in LE - increase efficiency of muscle contraction
Infection in any compartment, nowhere for infection to go, increased compartmental pressure, decreases blood flow to heart and lymphatic drainage
May become ischemic and permanently injured
Must perform fasciotomy
Injury to common fibular n
lose superficial and deep fibular n
Foot drop- toes don’t clear ground during swing phase
Compensation for foot drop:
Waddling gait - moving whole body
Swing-out fair - use hip abductors
Stoppage gait - step very high
Three parts of foot
Forefoot - lever during preswing phase of gait for forward propulsion
Midfoot- forms arch of foot, increases range of motion of foot, provides ability to adapt to uneven surfaces, connected to hind foot and forefoot by plantar fascia and muscles
Hindfoot- provides stability and shock absorption at heel strick
Arches of foot
Medial longitudinal calcaneous to phalanges
Lateral longitudinal calcaneous to phalanges
Transverse metatarsals
Medial and lateral act as unit , transverse spreading weight in all directions
Bony support
Medial arch
Talar head is keystone if medial longitudinal arch
Loss of support for talar head can result in flat feet
Dynamic support- muscles
Passive support - bones / ligaments
Ankle ligaments
Lateral collateral ligament (fibula to calcaneous)
Medial (deltoid) collateral ligament (tibia to calcaneous)
Plantar aponerosis has
Fracture-dislocations of ankle joints
Inversion = sprain of lateral collateral ligament
Eversion = sprain of medial collateral ligament
