20 - MSK Hip to Knee Flashcards
What is the sciatic nerve made of
where does it exit
consists of tibial and fibular nerves glueed together by epineurium
exits the greater sciatic foramen formed by the sacrospinous ligament
What are the abductors of the hip
What innervates
gluteus maximus (inf gluteal) and tensor facia lata (sup gluteal nerve)
work together through the iliotibal tract
Which muscle do gluteal nerves pass through
piriformis muscle (external rotator)
Where do adductor group muscles arise from
What innervates
pelvic bones (ischium and pubis) and interosseus membrane of the obturator foramen to insert on the medial shaft of the humerus and proximal tibia
obturator nerve
What is the adductor hiatus
hole through the muscle
“pause”
can contribute to the entrapment of the femoral nerve
What is the sartorius muscle
Waht does it do
What is it innervated by
part of anterior (extensor) compartment
flexion of hip
flexion of knee
external rotation of the thigh
femoral nerve
What are the three bones that make up the acetabulum
ilium
pubis
ischium
What are the ligaments of the hip
iliofemoral
pubofemoral
ischiofemoral
ligamentum teres
When is the hip most stable
when extended (tight ligaments)
flexion is unstable (loose ligaments)
When are hip dislocations likely to occur
which way does it dislocate
when in flexion
posterior direction
What can happen in a hip dislocation
compression or injury of the sciatic nerve
loss of muscle tone in the anterolateral compartment of the leg = foot drop
foreshortened interanal rotation
(adductor group)
What happens in a hip fracture
What could happen as a result
fracture of femoral neck
avascular necrosis
foreshortened external rotation
(iliopsoas via lesser trochanter)
What are the muscles of the quads
What are the innervated by
vastus medialis
vastus intermedius
vastus lateralis
rectus femoris
femoral nerve
What do the quads do
extension of knee (major function)
flexion of hip (minor function)
What are the muscles of the hamstrings
What innervates
semi-membranosus (medial)
semi-tendinosus (intermediate)
biceps femoris (lateral)
tibial nerve
What do the hamstrings do
flexion of the knee (major function)
extension of the hip (minor function)
Which muscles insert upon the medial aspect of the proximal tibia
goose’s foot
sartorius, gracilis, semi-tendinosus
femoral, obturator, tibial
three muscles from each compartment
where the three tendons on the inside of knee attaches to the lower leg
What does the bursa do
protects the tendons of the pes anserinus from the underlying bone (medial epicondyle) of the femur
What are the ligaments of the knee
lateral (fibular) and medial (tibial) collateral ligaments: keep knee stable
cruciate ligaments: prevents shin bone from sliding out in front of the tibial bone
menisci: improve the fit between the tibial plateau and the rounded femoral condyles
- medial
- lateral (undergoes conformation change as the knee moves through flexion and extension)
Which aspect of the femoral condyle interact with teh tibia when the knee is in extension
anterior
Which aspect of the femoral condyle interact with the tibia when the knee is in flexion
wider posterior
What does the popliteus muscle do
What innervates
contraction of the popliteus muscle –> external rotation of the femur + draws the lateral meniscus posterior
(to help unlock the extended knee)
tibial nerve
Which ligaments support the knee
collateral ligaments (lateral fibular and medial tibial) prevent lateral displacement of the tibia wrt the femur
Cruciate ligaments prevent anterior/posterior displacemnet of the tibial wrt the femur
Which cruciate ligament is smaller and weaker/more prone to tearing (sprains)
anterior cruciate ligament (acl)
prone to tearing when rotational forces are place on the knee
How to test the integrity of the ACL
perform and anterior drawer test
ability to open the drawer = ACL damage
When is the PCL prone to tearing
when the knee is hyperextended or a force is applied ot the anterior tibia when the knee is flexed
How to test the integrity of the PCL
perform a anterior drawer test
ability to close the drawer = PCL dmage
What can happen if forces are applied to the lateral aspect of the knee
injury to structures on the medial side of the knee (attached to one another)
- anterior cruciate ligament (ACL)
- medial collateral ligament (MCL)
- medial meniscus (MM)
