lower extremity Flashcards
what is one of the bodies most stable joint
the hip due to the deep ball and socket configuration
what makes up the pelvic girdle
the lower lumbar segments, sacral-iliac joints, symphysis pubis, hip joints and all of the ligaments and muscles that support it.
what types of tissue provide joint stability
bone, ligaments, and muscle(tendons)
the IT band gets tight with contraction of what 2 muscles
the TFL and the glute max
how is the femur vascularized
through the ligamentum teres and the circumflex arteries
when would there be a high suspicion of avascular necrosis
in hip dislocation, femoral neck fracture, and legg perthes or SCFF in children
where are ground reation forces the most in gait
at heel strike and toe off.
what is piriformis syndrome
entrapment of the static nerve due to tightness of the piriformis
gait compensation for a painful hip joint
lateral sway
gait compension for a weak gluteus medius
a contralateral hip drop positive trandelenburg sign
meniscus
the purpose is to cushion and promote joint surface congruency. intra articular and poorly supplied with blood (harder to heal)
what femoral condyle is larger the the other
medial is larger then the lateral which leads to natural valgus
what femoral condyle is higher then the other
lateral is higher then the medial
the patello-femoral articulation
to protect, increase function of the quad mechanism, if the patella is gone then you can lose 1/3 of quad strength
femoral anteversion leads to
internal rotation, in-toeing and lateral tracking concerns
femoral anteversion at birth and adulthood
30-35 degrees at birth
10-15 degrees at adulthood
joint play
only occurs in response to an outside force includes distractions (separation), glides (anterior and posterior), and tilts (valgus and varus stress
knee lock in open chain
the tibia externally rotates
knee lock in closed chain
the femur medially rotated
quads work to
de accelerate the body weight during the loading response
hamstrings work to
de-accelerate the knee extension at the moment of heel strike
lateral hamstrings create (blank) and prevents (blank)
external tibial rotation
the anterior-lateral translation of the tibia under the femur (why the hamstrings are important in ACLs
the medial hamstrings (pes ansirene) creates (blank) and prevents (blank)
internal tibial rotation
anterior- medial translation of the tibia under the femur
how many degrees of knee flexion and knee extension is needed for normal gait swing through
60 degrees of flexion and all of extension
when do tensile stresses across the extensor mechanism need to be limited?
-contusions and tears to the quadriceps
-Patellar fracture
-Patellar tendon rupture
-Osgood schlatters disease
how to avoid tensile stress on the knee extensors?
avoid quad contraction, avoid passive lengthening of the extensor mechanism, and rest
when the the compressive force of the patella the most
when the knee is in full flexion
contributing factors to medial collapse and lateral tracking
-increased femoral anteversion
-weakness in hip abductors and external rotators
-excessive foot pronation/ flat feet
-more common in females to to wider pelvis and Q angle
-leads to bowstring effect
the big 3 injury in medial collapse
MCL, Medial meniscal tear, ACL
ligaments of the foot
Medial: deltoid
Lateral (usually the most common to get torn): anterior talofibular, calcaneofibular, posterior talofibular
combined motion of foot pronation
abduction, dorsiflexion and eversion (valgus)
combined motion of the foot supination
adduction, planter flexion and inversion (varus)
how much weight does the big toe accept in stance and gait
1/2 of body weight
how much extension does first MTP need for gait push off
40-60 degrees
trimalleolar fracture
laterla malleoli fracture, fracture to the medial malleolus, fracture to the posterior tibial mortice
why are typical ankle sprains on the lateral side (inversion)
1) initial foot loading
2) boney support of fibular malleolus more distal then medial
3) lateral collateral ligaments are thinner and weaker
passive support to the medial longitudinal arch
talonavicular ligament, spring ligament, planter fascia
muscular attachment to the navicular
TP, TA, and fib longus
