Lecture: The Knee Complex Flashcards
3 articulating surfaces, form 2 distinct joints contained w/in a single joint capsule: (2 joints)
- patellofemoral joint
- tibiofemoral joint
2 types of swelling of the knee occur:
- localized swelling (i.e. bursal)
- generalized swelling (i.e. intra-articular; synovitis)
normally tibia has slight __ angulation in comparison to femur.
bowlegged=?
knock-kneed=?
- valgus
- (coxa)valga
- (coxa)vera
genu recurvatum=
- hyperextension of the knee
- higher among females
- & individuals with longer or “lax” ligs.
the tibiofemoral joint= __ end of femur & __ end of tibia.
the __ aspect of the femur= __ femoral __, separated by:
the anterior & posterior intercondylar areas serve as attachment sites for:
- distal; proximal
- distal; 2; condyles; intercondylar eminence
- ACL & PCL
the tibiofemoral joint is a __, or modified hinge joint.
joint stability is therefore dependent upon:
-static restraints:
-& dynamic restraints:
- ginglymoid
- (static)=joint capsule, ligaments & menisci
- (dynamic)=quadriceps, hamstrings & gastrocnemius
the femoral condyles project __ from the femoral shaft.
the __ lateral femoral condyle is __-__ & faces __.
the __-__ medial femoral condyle faces __.
- posterioly
- smaller; ball-shaped; outward
- elliptical-shaped; inward
the lateral epicondyle (of the femur) = origin for: (2)
the medial epicondyle (of the femur) = insertion for: (2)
- lateral head of gastrocnemius & lat. collateral lig.
- adductor magnus & medial collateral ligament
the __-__ width of the medial femoral condyle is greater than its lateral by __ cm.
the length of the articular surface of the medial femoral condyle is __ than the length of the lat. fem. condyle.
- anterior-posterior
- 1.7cm
- longer
proximal tibia is composed of __ plateaus, separated by the __ eminence, including the med. & lat. __ __.
the tibial plateaus are __ in the __ to __ direction.
in the ant. to post. direction, the medial tibial plateau is concave, while the lateral is __, producing an __ in lateral __.
- 2
- intercondylar
- tibial tubercles
- concave
- medial to lateral
- convex
- increase
- mobility
patellofemoral joint is a __ articulation.
dependent on both __ & __ restraints for its fxn & __.
the post. surface of patella can include up to _ facets, w/ _ on the med. & lat. surfaces.
- complex
- static & dynamic
- stability
- 7; 3
the patella is a very __, __-shaped bone.
situated in the __ notch.
& embedded in the __ of the __ __ muscle above & the __ tendon below.
it is fixed in the __ groove in __ & mobile in __.
- hard; triangular
- intercondylar
- tendon; quadriceps femoris
- patella
- trochlear; flexion; extension
the patellofemoral joint fxns to:
provide an __ w/ __ friction.
protect the __ aspect of the femur from __ & the quads from __ wear.
improve the __ appearance of the knee.
improve the moment(?) arm of the __.
DECREASES the amount of __-__ tibiofemoral __ stress placed on the knee joint.
- articulation; low
- distal; trauma; attritional
- cosmetic
- quads
- anterior-posterior; shear
the Quadriceps angle: aka? 2 lines drawn: male avg.= female avg.= >\_\_deg. are considered \_\_ & may be indicative of potential \_\_ of the patella.
- “Q” angle
- (1)=from ASIS to center of patella
- (2)=center of patella to tibial tubercle
- 8-14deg.
- 15-17deg.
- 20; abnormal; displacement
(increased Q-angle)
Bayonet Sign=
common in pts. w/ patellofemoral arthralgia=
- quads, patellar tendon & tibial shaft resemble french bayonet
- w/ the knee flexed 30deg., there is a failure of the tibia to derotate normally & failure of the patellar tendon to line up w/ the ant. crest of the tibia
patella stability is dependent on 2 factors:
purists (anatomists) classify the patella tendon as a __, b/c it serves as the connection b/w 2 bones (tibia & patella), but b/c it attaches the quads to the tibia, it fxns as a __.
- static & dynamic restraints
- ligament
- tendon
in a normal knee, the patella glides in a path: __-__ during flexion & extension respectively.
covering a distance of - cm w/ respect to the femur.
- inferiorly-superiorly
- 5-7cm
normal patellar posture w/ knee at 45deg. of flex.=
inf/lower patellar posture=
sup/higher patellar posture=
-patellar articular surface is squarely against the ant. femur
-represents patella BAJA
-represents patella ALTA (ALTitude is high in the sky!/sup.)
(*patella alta makes the patella less efficient in exerting normal forces)
the knee joint capsule is composed of a __, strong fibrous membrane.
the KJ is the __ synovial capsule in the body.
a __ membrane lines the inner portion of the KJC.
by lining the JC, the __ membrane excludes the __ ligs. from the interior portion of the knee joint, making them __ yet __-articular.
- thin
- largest
- synovial
- synovial
- cruciate
- extrasynovial; intra-articular
proximal tibiofibular joint:
an __ plane w/ a slight __ on the oval tibial facet &
slight __ of the fibular head.
has __ motion that its distal partner, the __.
- almost
- convexity
- concavity
- more; tail
Osgood-Schlatter’s Syndrome/Disease
aka?
partial disruption at the __ ligament-tuberosity __.
creating __ inflammatory changes.
__ stress on the knee causing __ at the tibial tuberosity.
commonly in __ usually during a “__ __”.
predisposing factors:
- osteochondritis of tibial tubercle
- patellar; attachment
- localized
- repetitive; traction
- adolescents; “growth-spurt”
- tight hamstrings, tight heel cord (achilles tendon) & tight quad m.’s
Osgood-Schlatter's Syndrome/Disease more in which gender? ages? \_\_, \_\_ & \_\_ over the tibial tubercle. pain on \_\_ or \_\_ stairs. Hx:
- males
- 10-15
- pain, swelling & tenderness
- ascending or descending
- single violent injury OR repetitive FLEX/EXT. movement
the STATIC stability of the KJC depends on 4 major knee ligaments:
(which provide a __ restraint to __ knee motion)
- anterior cruciate
- posterior cruciate
- medial collateral
- lateral collateral
- primary; abnormal
Primary Restraints of the Knee: anterior translation= posterior translation= valgus rotation= varus rotation= LATERAL rotation= MEDIAL rotation=
- ACL
- PCL
- MCL
- LCL
- MCL & LCL
- ACL & PCL
cruciate ligaments are different from those of other joints, in that they __ normal motion, rather than __ abnormal motion.
- restrict
- restrict
anterior cruciate ligament:
one of the most __ ligaments to knee __.
serves as a __ restraint to ant. __ of the tibia relative to the femur.
& a __ restraint to both __ & __ rotation in the __-weight bearing knee.
- important; stability
- primary; translation
- secondary; internal & external; non-weight
anterior cruciate ligament:
most common MOI=
__ kinetic chain, b/c?
- sudden deceleration w/ an abrupt change of direction/speed and or velocity & a fixed foot
- closed; b/c of foot on the ground
posterior cruciate ligament:
provides __-__% of the total __ to posterior translation of the tibia on the femur.
with the remaining _-__% being provided by:
- 90-95%; restraint
- 5-10%
- collateral ligs, post. portion of the med. & lat. capsules, & the popliteus tendon
posterior cruciate ligament:
MOI where the PCL can tear include:
- excessive hyperflexion (forced bending; i.e. falling not the shin w/ a ben knee and foot pointed)
- OR hyperextension (leg bent backwards)
dashboard injury=
- (i.e. in a car)
- where the knee is bent to a right angle and a sudden force drives the tibia backwards
the Medial Collateral Ligament:
aka?
the __ fibers of the ligament are __ in __, broad & fan shaped & can be __ palpated in this position.
the __ fibers are __ in __, & blend in with the capsule & the medial meniscus, making them __ to palpate.
- TIBIAL collateral ligament
- anterior; taut; flexion; easily
- posterior; taut; extension; difficult
the Lateral Collateral Ligament:
aka?
main fxn?
offers the majority of the __ restraint at __deg. of knee flexion & in full extension.
- FIBULAR collateral ligament
- resist varus forces
- varus; 25deg.
secondary restraints of the collateral ligaments include: (3)
- the structures in the post.-lateral & post.-medial corners of the knee
- the hamstrings & quads.
- the patellar ligament, oblique popliteal ligaments & the fibula
menisci:
__-shaped lateral & medial menisci.
attached on __ of the tibial __.
they are pieces of __ material that lie b/w the __ cartilage of the __ & the __.
- crescent
- top; plateaus
- fibrocartilage; articular; femur & the tibia
medial meniscus: semi-lunar or \_\_-\_\_. \_\_ & \_\_ than its lateral counterpart. sits in the \_\_ medial tibial plateau. \_\_ posteriorly than anteriorly.
- C-shaped
- larger & thicker
- concave
- wider
lateral meniscus:
rounder or __-__.
sits atop the __ lateral tibial plateau.
attached by __ ligaments.
__ & __ than its medial counterpart.
more __ than its medial counterpart.
__ menischofemoral ligaments attach to the lat. meniscus.
- O-shaped
- convex
- coronary
- smaller & thinner
- mobile
- two
menisci fxn: \_\_ transmission. \_\_ absorption. \_\_ lubrication. \_\_ stability. & \_\_ of movements.
- load
- shock
- joint
- joint
- guiding
you are __ times more likely to hurt the __ meniscus.
- 20X
- medial
a meniscectomy (define:) can \_\_ the shock-absorbing capacity of the knee by up to \_\_%.
- surgical removal of part of torn meniscus
- reduce; 20%
triad of O’Donoghue:
2 aka’s?
=rupture of the __, __ & __.
- “terrible triad” & “unhappy triad”
- MCL, ACL & medial mensicus
the __ margins of the menisci are __ than the __ margins & taper __ the center.
- outer
- thicker
- inner
- toward
the menisci are __ attached at their ends to the __area of the tibia.
- firmly
- intercondylar
the __ fibers which attach the menisci to the __ condyles, are called the medial & lateral __ ligaments.
- capsular
- tibial
- coronary
the middle genicular branch of the __ artery sends branches around the __ of the meniscus under the capsule.
small tortuous nonanastomotic vessels enter the __ fibrous zone of the meniscus.
- popliteal
- periphery
- outer
the __ third of the meniscus is __ & __ (won’t heal well).
- inner
- cartilaginous
- & avascular
the medial meniscus is attached to the=
-medial collateral ligament
the lateral meniscus is __ & more __ moveable than the medial.
- smaller
- freely
the lateral meniscus is attached to the=
-popliteus muscle
the bursae serve to reduce __ & to __ the movement of one body part over another.
- friction
- cushion
Prepatellar Bursitis=
- a fluid swelling occurs subcutaneously over the lower 1/2 of the patella and the upper 1/2 of the patellar lig. which is the distribution of the prepatellar bursa.
- the cause is any occupation that causes chronic trauma to the tissue overlying the patella, such as excessive kneeling or leaning forward.
Prepatellar Bursitis aka? MOI? a \_\_ blow to the area. \_\_ friction, such as from frequent kneeling. pt. symptoms= pain when?
- Housemaid’s Knee
- overuse
- direct
- chronic
- pain & swelling over the front of the knee
- bending or straightening the leg
Infrapatellar Bursitis:
aka?
__ occurs on both sides of the __ ligament, near the __ __.
the cause is repeated __ to the region of the __ __, including a variety of occupations such as:
- Clergyman’s Knee
- swelling
- patellar
- tibial tuberosity
- trauma
- tibial tuberosity
- roofers, painters & floor layers
popliteal fossa: superior lateral border= superior medial border= inferior borders= contents=
- biceps femoris tendon
- semitendinosous & semimembranosus
- medial & lateral head of the gastrocnemius
- posterior tibial nerve, popliteal artery & popliteal nerve
Morrant Baker's Cyst=? location at= protrudes when? sometimes dull pain when? may compress? often associated with? \_\_ joint disorder. \_\_ common.
- escaped synovial fluid in an enclosed membrane sac which is protruding thru the joint capsule of the knee
- midline of popliteal fossa
- when knee is extended & is not visible when knee is flex.
- when walking is produced
- popliteal vessels
- RA
- femorotibial
- very
Plica:
__ plica represents a remnant of the _ separate cavities in the synovial __ of the __ knee.
pain when __, closely resembles __ injury.
- synovial
- 3
- membrane
- developing
- irritated; meniscal
Retinacula:
formed from structures in the __ & __ layers of the KJ.
can be subdivided into __ & __ retinacula for __ examination & __ purposes.
- first & second
- medial & lateral
- clinical
- intervention
the major muscles that act on the knee joint complex=
- quadriceps
- hamstrings (semi-mem./semi-tend. & biceps femoris)
- gastrocnemius
- popliteus
- & hip adductors
extension lag=
- pt. may be unable to extend the knee thru the last 10deg. of motion, may only be able to w/ a great amount of effort
- occurs w/ quadriceps weakness
Helfet’s Helix=
- the knee cannot fully extend w/o some amount of external tibial rotation on the femur
- b/c of physical configuration of the knee joint & its cruciate ligaments
- ACL & PCL cause this rotation
major blood supply of the knee area= (3)
- femoral
- popliteal
- genicular arteries
neurology of the knee area=
- femoral (saphenous) nerve
- sciatic nerve (common peroneal palpable @ neck of fibula)
- tibial nerve
the position of the joint at the time of the traumatic force dictates=
-which anatomic structures are at risk for injury
the primary MOI in the knee are= (6)
- direct trauma
- varus or valgus force
- hyperextension
- flexion w/ post. translation
- twisting force
- overuse
