Exam 4: thigh and knee, leg ankle foot Flashcards
Q angle
ASIS and tibial tubercle to center of patella
normal = 12-15 deg
patella contact area
20 deg flex : inferior portion
45 deg flex: mid patella
90 deg flex: sup. patella
135 deg flex: med, lat patella
- as flexion increases, more of the patellar contact area increases –> distributes the forces over a greater area –>decreases pressure
- leg extension (closed chain): very small patellar contact area under max force during full extension –> very high pressure –>more susceptible to wear and tear and cartilage damage
Q angle:
- genu valgus (knock knee) and femoral anteversion
- genu varus
- normal
genu valgus: Q angle >20 deg
genu varus: Q angle <10 deg
*normal q angle = 12-15 deg
patellofemoral dysfunction
-tightness of ITB: pulls patella laterally–>lateral tilt
-weakness of VMO
Result: increased compressive forces on lat. condylopatellar facet during knee flex
clinically necessary knee ROM values
knee ROM: 0-130 deg
walking: need ~70 deg knee flex
stairs: need ~105 deg
getting in and out of chair: ~100 deg
ligaments: extra-articular structures
- quad tendon and patellar lig
- lateral patellar retinaculum
- fibrous expansion of vastus lateralis & ITB: reinforces anterolat jt cap. - medial patella retinacul.
- fibrous exp of vast. med. - MCL
- med femoral epicond –>med tib. condyle
- attaches to med. meniscus - LCL
- Oblique Popliteal Lig: fibrous exp. of semimemb T. (reinforce post. capsule)
- arcuate popliteal lig.
arcuate popliteal lig
straight part: fibular head to lat femoral condyle
arching part: fibers blend w/ oblique popliteal lig
intra-articular structures of knee (8)
- ACL:runs post-lat (ant horn of med meniscus–>intercondylar fossa side of lat fem condyle)
- PCL: runs ant-med from post to post horn of med menisc to intercondylar fossa side of med femoral condyle)
- med meniscus (C-shaped): attaches to MCL
- lat meniscus: ring shaped
- coronary lig: extend from jt cap, attach outer edge of med, lat menisci to tibial condyles
- transverse lig: connects ant horns of med-lat meniscus
* may be absent - post meniscofemoral lig:lat menisc to med fem condyle
* may be absent
* runs behind of and attaches to PCL - ant meniscofemoral lig: lat menisc to med fem condyle
* may be absent
* runs in front of and attaches to PCL
ACL & PCL bands
anteromedial band: tight w/ knee flex,lax w/ ext
posterolateral: tight w/ knee ext, lax w/ flex
*ACL always taut through whole range of motion
meniscal tears
outer peripheral tears repair well
inner 1/3 = avascular (do not repair well)
seldom removed
ACL tears
partial: debridement of fibers due to inflamm
complete: effusion due to blood vessel rupture
* instability: ant drawer test, lachmans
- ER of tibia: ACL and PCL not crossed–>less stability
- IR of tibia: ACL, PCL crossed –>more stability
menisci: common attachments of both
- capsule
- coronary lig
- horns
- transverse lig
medial meniscus: attachments
- MCL
- semimembranosus
lateral meniscus attachments
- popliteus
- meniscofemoral lig
functions of menisci
- adapt bones to each other
- shock absorption
- rotation and flex
- adapting changing curvatures to each other
- spreading synovial fluid
unhappy triad
MCL
Medial Meniscus
ACL
4 anterior bursae of knee
- suprapatellar (quad): articularis genu slides it away from moving patella
- prepatellar: between skin & patella
- superficial infrapatellar: between tibial tub & patellar tendon
- deep infrapatellar: near inferior pole of patella, inferior margin of fat pad
4 posterior bursae of knee
- gastroc
- popliteus
- semimemb
- pes anserine bursa
blood supply of knee
popliteal A
- superior med/lat genicular
- inferior med/lat genicular
- middle genicular
sensory innervation of knee
- obturator
- femoral
- common fibular (peroneal)
- tibial
anterior compartment of thigh
- inguinal lig to ant knee
- femoral triangle
- adduct canal
- quads
- cutaneous innervation:
- femoral branch of genitofemoral
- ilioinguinal
- lat fem cutaneous
- intermed femoral cut
- med femoral cut
- obturator
muscles of ant compartment
- IP: flex hip, trunk
- sartorius: flex, abd, ER of femur @ hip; flex knee
- pectineus: flex, add, assists in med rot
- quadriceps femoris (femoral N: L2,3,4)
- rectus femoris: ext knee, flex hip
- vast lat: ext knee, lat patella
- vast med: ext knee, med patella
- vast interm: ext knee - articular genu: moves suprapatellar bursa
patellofemoral syndrome (PFS)
anterior compartment of thigh
Abnormal lat patellar movement
-associated w/: tight ITB, weak VMO
Chondromalacia of patella: wear of articular cartilage facets (esp lateral)
plica syndrome
inferomedial quadrant of knee usually the most painful region.
A painful taut band of tissue that emanates from the central portion of the medial patella may often be palpated (3 o’clock position)
femoral nerve
L2-4 (post division) of lumbar plexus
Motor to ant thigh
sensation to skin of ant/med thigh
*intermed femoral cutaneous N: ant thigh
*med femoral cutaneous N: med thigh
Saphenous N: terminal branch innervates skin of med lower leg and medial heel
*infrapatellar branch to skin of ant & med knee
arterial branches off external iliac A to ant thigh
External iliac A
- infer epigastric, deep circumflex iliac
- femoral A
a. superficial epigastric (ant abdominal wall)
b. superficial circumflex iliac (sup/lat inguinal area)
c. external pudendal: medial inguinal area, ext genitalia
d. profunda femoris
i. med circumflex (fem head, neck)
ii. lat circumflex (fem head, TFL, lat VL, VI)
iii. perforating A (hamstrings, add magnus, add brevis)
adductor (hunter’s) canal
ant: middle 1/3 sartorius and fascia from VM to add magnus, longus
lat: VM
med: Add long & magnus
Contains: femoral A, V, saphenous N
*vessels leave canal through add hiatus (in add magnus), then run post in popliteal fossa and become popliteal A, V
medial compartment of thigh
obturator N, A, V: pass through obturator canal
Adductors: obturator N L2-4 (ALL adduct femur)
1.gracilis: assist knee flex, IR tibia
2.adduct long: assist hip flex,IR
3.brevis:assist hip flex, IR
4.magnus: assist EXTand IR @ hip
5.obturator externus: obturator N (add, ER femur)
medial compartment thigh innervation
obturator N: all adductors, gracilis
femoral N: pectineus
tibial N: adduct magnus (L4 component)
medial compartment thigh vasculature
- Obturator a
- Medial Femoral Circumflex a
- Profunda Femoris a
iliopsoas and obturator N
obturator N exits through iliopsoas
Posterior Compartment of Thigh
- Tibial N
- Common Peroneal(fibula) N
- ProfundaFemoral A
- ProfundaFemoral V
- Hamstring Muscles
- Ischialpart of add Magnus
sural N
- cutaneous innervation for posterolateral leg, lat calcaneous
- arises from tibial N & per. communic. branch of common peroneal N.
- branches
- lat. calcaneal
- lateral dorsal cutaneous
branches of sciatic N
- tibial N
- med. calc. N
- med/lat plantar N
- sural N (also shares connect. from common peroneal N)
a. lat calc.
b. lat. dorsal cutan. - common peroneal N
a. lat. sural cutaneous
b. superficial peroneal–>med & intermed. cutan. N’s
c. deep peroneal –> med & lat branches (muscles)- cutaneous innervat. for skin between 1st/2nd toe
Common or Deep Fibula N.damage
weakness in:
- Ankle dorsiflexion(drop foot)
- Foot eversion
- Common or superficial fibula
- Toe extension
- Common or deep fibula
Posterior Compartment Muscles
- Biceps Femoris: L5,S1,2
- Long head –Tibial N
- Short head –Common Peroneal N - Semimembranosus: Tibial N L5,S1,2
- Semitendinosus:Tibial N L5,S1,2
- Adductor Magnus (ischial part):Obturator L2,3,4 and Sciatic N
post compartment thigh innervat
Tibial N:
- long head biceps femoris
- semimembranosus
- semitendinosus
Common peroneal N:
-short head of biceps femoris
post thigh compartment vasculature
- perforating branches of profunda femoris A
- inferior gluteal NAV
- popliteal NAV
hamstring tightness
- post pelvic rotation
- decreases lumbar lordosis
- can lead to strains, especially during eccentric activity