FEMUR & KNEE Flashcards
TIBIOFEMORAL JOINT (knee joint) - type
synovial, hinge, diarthrosis, biaxial
TIBIOFEMORAL JOINT - articular surfaces
convex medial & lateral femoral condyles
concave medial & lateral superior articular surfaces of tibia (tibia plateau)
TIBIOFEMORAL JOINT - major knee ligaments
INTRACAPSULAR:
-anterior cruciate ligament (ACL)
-posterior cruciate ligament (PCL)
~medial & lateral menisci
EXTRACAPSULAR:
-medial collateral ligament (MCL)
-lateral collateral ligament (LCL)
~fibrous capsule
~patellar
tibiofemoral joint - ANTERIOR CRUCIATE LIGAMENT
from medial aspect of lateral femoral condyle to anterior aspect of tibial intercondylar eminence
-resists anterior translation & medial rotation of tibia on femur
-TAUT in HYPEREXTENSION
tibiofemoral joint - POSTERIOR CRUCIATE LIGAMENT
from posterior aspect of intercondylar eminence to lateral aspect of medial femoral condyle
-resists posterior translation of tibia on femur
-TAUT in HYPERFLEXION
tibiofemoral joint - MEDIAL COLLATERAL LIGAMENT (MCL)
(tibial collateral ligament)
resists VALGUS forces
tibiofemoral joint - LATERAL COLLATERAL LIGAMENT (LCL)
(fibular collateral ligament)
resists VARUS forces
tibiofemoral joint - MENISCUS
acts to disperse weight evenly & reduce friction with movement
medial & lateral meniscus
MEDIAL: attached to MCL & semimembranosus muscle/ tendon
LATERAL: attached to PCL & popliteus muscle
TIBIOFEMORAL JOINT - movements
-flexion
-extension, hyperextension
-rotation (internal/external)
-rolling
-gliding
tibiofemoral joint - BURSAE
SUPRAPATELLA
PREPATELLA
INFRAPATELLA
SEMIMEMBRANOSUS
tibiofemoral joint - END FEELS
NORMAL:
-flexion: soft tissue/ bony approximation
-extension: elastic/ firm
ABNORMAL:
-boggy: joint effusion, ligamentous pathology
-springy block: loose body (displaced meniscus)
tibiofemoral joint - OPEN KINETIC CHAIN
flexion: tibia rolls & glides on posterior femur
extension: tibia rolls & glides on anterior femur
tibiofemoral joint - CLOSED KINETIC CHAIN
flexion: femur rolls & glides on posterior tibia (squatting)
extension: femur rolls & glides on anterior tibia (moving from squat to standing)
GENU VALGUM
Q angle greater than 22° in women & 18° in men
“knocked knees”
GENU VARUM
Q angle less than 0°, distal tibia points medially
“bow legs”
GENU RECURVATUM
hyperextension of knee
PATELLOFEMORAL JOINT - type
synovial, plane, diarthrosis, triaxial
PATELLOFEMORAL JOINT - function
-patella = small bone in front of knee, embedded in quadriceps tendon
-sesamoid bone
-acts to INCREASE BIOMECHANICAL LEVERAGE of quadriceps muscle
-slides in groove of femur as knee flexes & extends
-“floats” -> dependant on proper muscle balance to maintain central position
PATELLOFEMORAL JOINT - articular surfaces
concave posterior surface of patella
convex trochlear surface of distal anterior femur
PATELLOFEMORAL JOINT - ligaments
patellar ligament, medial & lateral patellofemoral ligaments
PATELLOFEMORAL JOINT - movements
superior/ inferior glide
medial/ lateral glide, tilt, rotation
PROXIMAL/ SUPERIOR TIBIOFIBULAR JOINT
type: synovial, plane, diarthrosis, uniaxial
articular surfaces: articular facet on fibular head, facet on lateral tibial condyle
ligaments: fibrous capsule, anterior & posterior tibiofibular, lateral collateral, upper interosseous membrane
movements: gliding
MID-TIBIOFIBULAR JOINT
type: fibrous, interosseous, amphiarthrosis, uniaxial
articular surfaces: interosseous membrane connecting shafts of tibia & fibula
ligaments: interosseous membrane
movements: slight
DISTAL/ INFERIOR TIBIOFIBULAR JOINT
type: fibrous, syndesmosis, amphiarthrosis, uniaxial
articular surfaces: articular area on inferior end of fibula, facet on inferior end of tibia
ligaments: interosseous membrane (lower), anterior & posterior inferior tibiofibular
movements: gliding
SCREW HOME MECHANISM
*key element to knee stability for standing upright
-knee extension: tibia glides anteriorly on femur & PCL elongates
-during last 20° of knee extension, anterior tibial glide persists on medial condyle of tibia
-prolonged anterior glide on medial side = external tibial rotation
-reverses during knee flexion
screw home mechanism - GATE CYCLE
-tibia internally rotates during swing phase (knee flexion)
-tibia externally rotates during stance phase (knee extension)
FEMORAL TRIANGLE
-inguinal ligament
-sartorius
-adductor longus
ADDUCTOR/ SUBSARTORIAL/ HUNTER’S CANAL - borders
-anteromedial: sartorius
-lateral: vastus medialis
-posterior: adductor longus & magnus
POPLITEAL FOSSA - borders
-semimembranosus
-biceps femoris
-plantaris
-gastrocnemius (long & short head)
PES ANSERINE
insertion point for 3 muscles:
-sartorius
-gracilis
-semitendinosus (hamstring)
SESAMOID BONES
-small independent bone/ bony nodule that develops in a tendon that passes over an angular structure
-PATELLA = largest sesamoid bone in body
-example: FABELLA -> occurs in tendon of lateral head of gastrocnemius (present in 39%)
ANTERIOR FEMORAL GROUP
-tensor fascia lata (TFL)
-sartorius
-quadriceps: rectus femoris, vastus lateralis, vastus intermedius, vastus medialis
-articularis genu
MEDIAL FEMORAL GROUP
-adductor longus
-adductor brevis
-adductor magnus
-pectineus
-gracilis
POSTERIOR FEMORAL GROUP
-hamstrings: biceps femoris, semimembranosus, semitendinosus
QUADRICEPS
-rectus femoris
-vastus lateralis
-vastus intermedius
-vastus medialis
HAMSTRINGS
-biceps femoris (long & short head)
-semimembranosus
-semitendinosus
ADDUCTORS
-pectineus
-adductor brevis
-adductor longus
-adductor magnus
-gracilis
ANTERIOR CRURAL MUSCLE GROUP - actions & nerve
-tibialis anterior
-extensor digitorum longus
-extensor hallucis longus
*fibularis (peroneus) tertius
~all dorsiflex foot
~deep fibular (peroneal) nerve
LATERAL CRURAL MUSCLE GROUP - actions & nerve
-fibularis (peroneus) longus
-fibularis (peroneus) brevis
~all plantar flex & evert foot
~superficial fibular (peroneal) nerve
POSTERIOR CRURAL MUSCLE GROUP (DEEP) - actions & nerve
-tibialis posterior
-flexor digitorum longus
-flexor hallucis longus
~all plantar flex foot
~tibial nerve
POSTERIOR CRURAL MUSCLE GROUP
-plantaris
-gastrocnemius
-soleus
-popliteus
~tibial nerve
PLANTAR FLEXION (muscles)
-soleus
-gastrocnemius
-plantaris
-tibialis posterior
-peroneus (fibular) longus & brevis
-flexor digitorum longus
-flexor digitorum hallucis
DORSIFLEXION (muscles)
-tibialis anterior
-extensor digitorum longus
-extensor digitorum hallucis
INVERSION (muscles)
-tibialis anterior
-tibialis posterior
EVERSION (muscles)
fibularis longus, brevis, tertius
what two muscles insert into the IT band?
TFL
gluteus maximus
where does the IT band insert?
Gerdy’s tubercle of tibia close to knee
