Hip and Knee Joint Flashcards
hip joint
synovial ball and socket so 2nd most mobile in body
stable by depth of socket, strong capsule, numerous muscles cross
femoral head
covered by articular cartilage except @ fovea capitis for ligament of head of femur attach
acetabulum
lunate surface = c shaped rim, covered by articular hyaline cartilage bc direct contact with head femur
acetabular notch = passage for blood vessels and ligament of head femur
acetabular labrum
lip of fibrocartilage to inc depth of socket
-cont with transverse acetabular lig across notch
acetabular fossa
deeper part of socket, does not articulate with femur but cont with acetabular notch
fat pad covered by synovial membrane
synovial joints
general review
most mobile kind of joint
has fibrous CT joint capsule strengthend by extracapsular ligs
-lined by synovial membrane
-synovial cavity
-articular cartilage
-synovial fluid lubricates cartilage
-blood and nerve supply
fibrous joint capsule
most fibers spiral from pelvis to femur
reinforced by 3 intrinsic ligaments
lined by synovial membrane as a sleeve around neck of femur
annular ligament
aka zona obricularis
intracapsular deep to spiraling fibers
wrap around neck of femur
iliofemoral ligament
anterior and superior ligs, Y shape
-from AIIS and rim ilium to intertroch line
strongest ligament in body
limits hip extension by winding to inc stable
pubofemoral ligament
anterior and inferior ligs
-from obturator crest/pubis to fibrous layer of joint capsule femur
will limit hip abduction by tightening during extension/abduction
ischiofemoral ligament
posterior lig
-from ischial part acetabular rim to superior and lateral femoral neck
limits medial rotation
head of femur ligament
intracapsular/ articular
deep to transverse acetabular lig
has foveolar A running with it but can be absent
blood supply
hip joint
- retinacular A from medial circumflex femoral, some from lateral circumflex
-runs deep to annular lig and synovial mem - artery to head of femur from obturator, medial side of head only but insufficient
hip fractures
aka femoral neck so danger retinacular A > avascular necrosis bc cut off main supply
hip impact injuries or falls
cruciate anastomosis
- obturator + branches
- deep femoral branches (medial and lateral circumflex)
- gluteals (superior and inferior)
descending branch of lateral goes to genicular anastomosis
articular innervation
to joint capsule/joint itself aka sensory/proprioception/nociception
-femoral N
-obturator
-sup gluteal
-N to obturator quadratus
hilton’s law
nerves supplying muscles that extend directly across/act on given joint will also inn it
cutaneous innervation
hip
- lat femoral cutaneous N ant/lat
- superior and inferior cluneal post
knee joint
general
synovial hinge joint, largest in body
-b/t femoral and tibial condyles + patellofem articulation
-fibula is not part of knee joint
knee joint functions
bears more weight than hip
flex/extend + rotate femur vs fixed tibia when locking/unlocking extended knee
knee most stable when fully extended
menisci
medial: c shaped, broader, less mobile, attaches to MCL
lateral: more closed circle
fibrocartilage shock absorbers + improve fit of condyles to inc stability
menisci ligaments
transverse lig of the knee: b/t anterior margins of both menisci
coronary: short vertical to anchor menisci to margins of tibial condyles
tendons that stabilize knee
muscular cage around knee so can strengthen
-quads tendon/patellar (ant)
-pes anserinus (SGT FOT) medial
-biceps femoris insertion (lateral)
-gastrocnemius (posterior)
knee joint capsule
fibrous external capsule-thin and gaps, thickened in certain areas aka intrinsic ligs
-anterior gap: quads tendon/patella/pat lig
-posterolat gap: popliteus tendon exits
attach to femur superiorly and tibia inferior
synovial membrane knee
lines capsule but not contact with cartilage
-diverts from capsule posteriorly
joint cavity cont with major large knee bursas
where ACL/PCL attach (intercondylar) not intrasynovial
capsular ligaments knee
extrinsic: lateral collateral (LCL)
intrinsic: medial collateral (MCL), oblique popliteal, arcuate popliteal
lateral collateral ligament
LCL
aka fibular collateral lig
-from lat epicondyle of femur to lateral fibular head
-separated from lateral meniscus by popliteus tendon
-splits tendon of biceps femoris
reinforce lateral side knee + tenses with extension
rounder/thicker than medial
medial collateral ligament
MCL
aka tibial collateral lig
-from medial femoral epicondyle to superomedial prox tibia + tibial medial condyle
-deep to pes anserinus
-adhered to medial meniscus
reinforce medial side knee + tense with extension
oblique popliteal ligament
continuation of semimembranosus tendon
reinforce posterior side of joint by spanning intercondylar fossa
nike swoosh
arcuate popliteal ligament
has two heads
-lateral to femoral lateral epicondly
-medial arches over popliteus tendon, blends with oblique
reinforce joint capsule posterolat
intra-articular ligaments of knee
2 cruciate ligs = ACL + PCL
2 menisci-tibia ligs = transverse + coronary
anterior cruciate ligament
ACL
medial aspect of lat femoral condyle to anterior intercondylar area of tibia
limits extension + prevent ant displacement
posterior cruciate ligament
PCL
from lat medial femoral condyle to post interconylar area tibia
limit flexion + prevent posterior displacement
-main stabilizing factor when weight bearing flexed like walking downhill
drawer signs
- anterior = tibia slides anterior w/o resistance, ACL torn
- posterior = tibia slide posterior w/o resist, PCL torn
blood supply knee joint
5 genicular arteries from popliteal A
1. superior lateral
2. superior medial
3. middle
4. inferior lateral
5. inferior medial
genicular anastomosis
- popliteal A > genicular
- femoral A > deep fem (>descending lateral circumflex) and descending genicular
- anterior tibial A > ant tibial recurrent and post tibial recurrent
- circumflex fibular A
nerve supply knee joint
articular
articular branches for motor to muscles crossing
-femoral N + tibial N + common fibular
cutaneous innervation knee
-intermediate femoral cutaneous branches
-posterior femoral cutaneous
-saphenous
-lateral sural cutaneous
