May31 M3-Anatomy LL 2 Flashcards
landmarks on femur other than those near the hip
- gluteal tuberosity (post, below intertroch crest)
- shaft of the femur
- linea aspera (a rough line posteriorly, below glut tuberosity)
- adductor tubercle (bump in back of lower femur, medially
distal femur name of the parts
- medial and lateral epicondyles = bumps in bottom
- medial and lateral condyles = articular surfaces
landmarks on the fibula
- head
- neck
- shaft
name of joint tibia - fibula
tibiofibular joint
landmarks on tibia
- tibial tuberosity (anterior)
- soleal line (posterior. goes medial distal to lateral proximal. so towards head of fibula)
structure separating tibia and fibula
interosseus membrane. has 2 holes one on top and one on bottom
how to do lateral (external) and medial (internal) rotation of the leg (knee)
- flex knee 90 degrees and move foot outwards (but no eversion, inversion)
- this rotates the leg
valgus deformity is what
- knees bend outwards (tibia bent outwards)
- bow legs
varus deformity is what
- knees bend inwards
- knock knees
genu recurvatum is what
hyperextension of the knees in the back due to either of
- hamstring weakness or injury
- non-inflammatory CT diseases (Marfan, Ehlers-Danlos)
hamstrings medially to laterally in the back
- semimembranosus
- semitendinosus
- biceps femoris (long head covering short head. short head is deeper)
true hamstrings
- semimembranosus
- semitendinosus
- long head of biceps femoris
semimembranosus O, I, F, N
- O: ischial tuberosity
- I: upper tibia (posteromedially)
- F: extend hip, flex knee. + medial rotation of tibia
- N: tibial n.
semitendinosus O, I, F, N
- O: ischial tuberosity
- I: pes anserinus (upper tibia anteromedially)
- F: extend hip, flex knee. + medial rotation of tibia
- N: tibial n.
long head of biceps femoris O, I, F, N
- O: ischial tuberosity
- I: head of fibula
- F: extend hip, flex knee
- N: tibial n.
short head of biceps femoris O, I, F, N
- O: posterior surface of shaft of the femur
- I: head of fibula
- F: flex the knee only
- N: common fibular n.
functions of hamstrings in the gait cycle
- extension of hip on stance leg during reversal of fore-aft shear (to swing the swing leg forward)
- flexion of the knee on swing leg during toe-off and foot clearance phases (end of stance and beginning of swing)
nerves to the thigh
- back: sciatic splits in tibial n. (medial) and common fibular n. (lateral)
- back: posterior cutaneous n. emerges medial to sciatic n.
- front: obturator n. (L2,3,4) comes on medial side
- femoral n. (L2,3,4) comes in middle of anterior thigh
other name for common fibular n.
common peroneal n. (peroné = old name for fibula)
other muscle that the tibial n. innervates in the back of the leg
adductor magnus hamstring portion
adductor magnus hamstring portion O, I, N and F
- O: ischial tuberosity
- I: adductor tubercle (near where semimebranosus inserts bc is bottom of femur posteromedially)
- N: tibial n.
- F: extend the hip
variations in sciatic n. exiting near piriformis
- pass through piriformis instead of below
- pass above piriformis instead of below
- note: post cut nerve of the thigh is always below piriformis medial to scaitic n.
blood supply to the thigh until femoral a.
- aorta gives 2 common iliacs
- common iliac makes external iliac and internal iliac a.
- internal iliac a. gives sup and inf gluteal a.
- external iliac a. becomes femoral a. below inguinal ligament
blood supply to the thigh after femoral a.
- femoral a. gives a deep femoral a. laterally
- femoral a. gives medial and lateral circumflex femoral aa. medially and laterlaly
- deep femoral a. gives 4 arteries called perforating aa. that go to the posterior thigh by piercing through adductor magnus adductor portion
what supplies blood to the hamstring
perforating arteries
adductor magnus two portion and position relative to each other
-adductor magnus adductor portion is lateral
-adductor magnus hamstring portion is medial
(but whole muscle is very medial)
adductor hiatus is what
hole created by separation of adductor magnus portions, and adductor magnus hamstring portion sending a tendon to the adductor tubercle
4 condyles in the knee
- lateral femoral condyle
- medial femoral condyle
- lateral tibial condyle
- medial tibial condyle
does the tibia have epicondyles
no. condyles only
medial collateral ligament of the knee does what
- attaches from medial epicondyle of femur to medial surface of tibia
- attaches to the joint capsule
- attaches to the medial meniscus
menisci are what
pads of cartilage between two bones
consequence of MCL attaching to the medial meniscus, clinically
MCL is more likely to get damaged
LCL (lateral collateral ligament of the knee) does what
- attaches from lateral epicondyle to the head of the fibula
- DOES NOT attach to cartilage (menisci) and is not fixed
- DOES NOT attach to the joint capsule
consequence of LCL not attaching to lateral meniscus, clinically
less likely to get injured
medial dislocation of the knee definition
tibia going medial
movements that the MCL and LCL prevent and that the knee can’t do
- prevent ABDuction and ADDuction (of the tibia)
- limit rotation of the tibia
- prevent medial and lateral dislocation
quadriceps femoris tendon attaches where
to patella - to patellar ligament (tendon) - to tibial tuberosity (on tibia)
how to test for collateral ligaments
- MCL: hold knee steady, put hand on lateral side of knee, and push knee medially as if trying to ABDuct the tibia
- LCL: hold knee steady, put hand on medial side of knee, and push knee laterally as if trying to ADDuct the tibia
anterior and posterior cruciate ligaments take what trajectory in the knee joint
FUMBUL (FUM for post. BUL for ant)
- forward upward medial (FUM) for PCL. so PCL starts (its bottom) medial in back.
- backward upward laterally (BUL). so ACL starts (its bottom) lateral in front
ACL and PCL connect what two bones
femur and tibia
so only LCL connecting femur to fibula
movements that the ACL and PCL prevent
- twisting
- anterior and posterior dislocation
options for cruciate ligaments surgeries (repairs)
- tendon from cadaver
- tendon from a muscle of the medial thigh
- patellar tendon
tests for assessment of ACL and PCL
- Lachman’s
- anterior drawer (ACL)
- posterior drawer (PCL)
shape of the lateral meniscus
nearly circular, O-shaped
shape of medial meniscus
crescent shaped, C-shaped
thickness of menisci
- thicker on outside
- thinner on inside
- eventually hole (no more meniscus)
function of menisci
- wedge-shaped, fibrocartilaginous pads
- cushioning + give depth to the joint (like the labrum of the acetabulum would do), so are kind of a socket
diff portions of menisci
each has a posterior horn and an anterior horn
diff tears of menisci
- radial tear (straight line from inside to outside but not complete cut)
- vertical tear (perpendicular to radial, somewhere in meniscus)
- bucket-handle tear (like vertical but curved, lining the very outside surface)
blood supply to menisci
- most exterior third has a rich blood supply and can repair if is torn.
- inner two-thirds lack blood supply (white zone). tears can’t heal + thin, worn cartilage
tx for radial tear
partial menisectomy if irritating
tx for tears near outside surface like vertical, bucket-handle tear
sutures (to sew the meniscus back in place)
what can happen to little tears like radial tears
can get caught and the knee will catch when it is bent. this can cause inflammation
capsule of the knee joint wraps around what
- around the whole knee except the LCL (passes deep to it) and the patellar ligament (tendon).
- the fat around the knee is within the joint capsule
what is found deep to the patellar tendon immediately
infrapatellar fat pad (is inside the joint capsule)
function of fat in the knee joint
cushioning
joint capsule of the knee is lined by what
a synovial membrane
bursas in the knee are what
- fluid filled structures found between two surfaces
- fct = reduce friction between these 2 moving surfaces
- can get bursitis if there is inflammation of the fluid-filled structure (bursa) as in the hip
- 11+ bursae in the knee
what’s a Baker’s cyst (a gastrocnemio-semimemrabnosus bursa)
- painful swelling behind the knee
- cause = outpouching of the JOINT CAPSULE (get a synovial popliteal cyst)
- cause of this outpouching = increase in intra-articular pressure. caused by RA for example
where Baker’s cyst occurs and why
- medial part of popliteal fossa (between semimembranosus tendon and medial head of gastrocnemius, near posteromedial femoral condyle)
- the gastrocnemio-semimembranosus bursa there is weak
tx of Baker’s cyst
(not much)
- aspiration
- CS
- ice, etc.
muscles you find in the popliteal fossa
- semimembranosus
- semitendinosus
- biceps femoris
- gastocnemis medial head and lateral head
- plantaris
nerves in the popliteal fossa
- tibial n. (came from sciatic n.) travels between 2 heads of gastrocnemius
- common fibular n. (from sciatic n.) is more lateral than tibial n. and runs along the biceps femoris tendon and wraps around the anterior leg below head of fibula
in the popliteal fossa, small nerves found between tibial n. and common fibular n.
sural nerves (are cutaneous)
- medial sural n. (comes from tibial n.)
- lateral sural n. (comes from common fibular n.)
cutaneous innervation to glutes region
- medial and middle = clunial nerves
- lateral = lateral cutaneous nerve of the thigh (from lumbar plexus)
cutaneous innervation to back of the thigh
- medial = cutaneous branch of obturator n.
- middle = posterior cutaenous n. of the thigh
- lateral = lateral cutaneous n. of the thigh
cutaneous inn. to back of the leg
upper half: -medial = saphenous n. (terminal branch of femoral n.) -middle = medial sural n. -lateral = lateral sural n. lower half: -medial = saphenous n. -lateral = superficial fibular n.
what happens with the femoral a. after it gave its branches in the anterior thigh
crosses to the back through the adductor hiatus. changes name after hiatus to become popliteal a.
branches of popliteal a to the knee
4 vessels
- lateral superior genicular a.
- lateral inferior genicular a.
- medial superior genicular a. (closest to hiatus)
- medial inferior genicular a.
- they all wrap around the knee and anastomose*
