test2 Flashcards
What is the largest joint of the knee complex?
The tibiofemoral joint.
Name the 3 joints of the knee and what type of joint they are?
Tibiofemoral- complex joint, patellofemoral- compound joint, proximal tibiofibular- simple joint.
The knee complex is the most common site of what type of impairment?
Permanent impairment in the lower limb
There are large forces at what 2 joints in the knee complex and this is due to what?
Tibiofemoral and patellofemoral due to very long levers.
What is the posterior compartment of the knee and what is the anterior compartment of the knee?
Posterior- tibiofemoral joint. Anterior- Patellofemoral joint.
At which knee joint is compression greater in the tibiofemoral or the patellofemoral?
Tibiofemoral
At which knee joint is distraction greater in the tibiofemoral or the patellofemoral?
patellofemoral
What are the femoral condyles like?
Egg shaped and separted by a fossa.
Will the radius of the femoral condyles be larger anterior or posterior?
Anterior.
What will the significance of egg shaped femoral condlyes be?
They will need a variable socket to articulate with the tibia and that is what the menisci are for.
What is conjoint rotation of the knee?
Screw home mechanism which is external rotation seen in the last few degrees of knee extension.
Conjoint rotation pivots around what?
The lateral femoral condyles during extension.
Whatis the direction of angulation of the femoral condyles and what is the reason for this angulation??
Posterior angulation to increase flexion and decrease extension of the knee.
What will valgus and varus mean?
Valgus- distal part bent outward (abducted), knocked kneed. Varus- distal part bent inward (adducted), bowlegged.
Which femoral condyle will have the longer larger articulare surface? Why?
Medial. It allows for conjoint rotation and more sliding to occur on the medial side.
The medial femoral condyle will also have a larger epicondyle, but why?
Has the adductor tubercle to receive the adductor magnus hamstring portion
What will the angle of the medial femoral condyle be like?
It will be more oblique than the lateral.
Which femoral condyle will extend more distally and what can this lead to?
Medial and this causes valgus of the knee.
What is the pivot point of conjoint rotation?
The shorter smaller articular surface of the lateral femoral condyle. (more spin occurs on the lateral condyle than medial condyle)
What muscle originates on the smaller lateral femoral epicondyle?
Politeus inserts between the epicondyle and condyle
What will the angle of the lateral femoral condyle be like?
Less oblique A-P.
The tibial femoral rotation of the skrew home mechanism happens when?
The last 15-0 degrees of extension of the knee.
What occurs with the tibia when the knee complex flexes?
Tibia rotates medially
What occurs with the tibia when the knee complex extends?
Tibia rotates laterally
What degree of tibia angulation classifies Genu Valgum?
Greater than 15 degrees that the tibia is angled outwards
What degree of tibia angulation classifies Genu Varum?
Less than 5 degrees that the tibia is angled outwards
What foot motion does genu valgum increase?
Pronation of the foot (greatest compensator)
What is femoral torsion?
anetversion ( degree to which an anatomical structure is rotated forwards (towards the front of the body) or backwards (towards the back of the body) respectively, relative to some datum position)
What is the normal femoral torsion or anteversion?
10-20 degrees.
What is an anteverted femur?
one rotated forward more than 20 degrees.
What will an anteverted femurs impact be on the knee?
Medial orientation.
What is a medial orentation of the the patella aka?
Squinting patella. (often seen with an anteverted femur)
What is a common compensation for a anteverted femur?
Genu valgum.
What is a retroverted femur?
One that has femoral torsion of 10 degrees or less.
What is the impact on the knee for a retroverted femur?
Lateral orientation.
What is the common compensation for a retroverted femur?
Genu varum.
What is a squinting patella?
Patella faces medially and increases external tibial torsion
What is the superior surface of the tibial condyles like?
Flat with tibial spines.
What is the purpose of the tibial spines?
Attachment site for ACL and menisci, and to resist side to side translation and rotation.
Are the tibial facets on the tibial plateau concave or flat?
Flat they are not concave.
Which tibial facet is larger medial or lateral?
Medial is larger to accommodate for the size of the femoral condyles
What allows for the tibial facets to be congruent with the femoral condyles?
The menisci improves the fit
What is the angle of the proximal tibia like? Why?
Posterior angulation. To increase flexion ROM.
What attaches to Gerdy’s Tubercles of the tibia?
Iliotibial band insertion
What type of torsion occurs at the tibial condyles d/t the ITB?
External tibial torsion
Where is the patellar surface of the femur at?
The anterior distal femur. Anterior to condyles.
What is the patellar surface of the femur like?
It has a medial facet/lip a lateral facet/lip and a central groove.
Which facet/lip of the anterior distal femur is bigger? Why?
Lateral because the patella wants to go laterally and this keeps it from displacing.
What is the significance of a small lateral facet and lip (shallow groove)?
Leads to patellar instability
What is the anterior distal part of the femur (facets/lips) lined with?
Hyaline cartilage.
What is the main function of the patella?
Increase angular pull of quadraceps (increase leverage at extension).
What is the shape of the patella like?
Triangular with the apex pointing down.
What is the posterior part of the patella like?
Medial and lateral facet with a central ridge, and once and a while there will also be an odd medial facet.
What is the purpose of the central ridge on the patella?
makes bone more wedge shaped.
What will cause the patella to have the odd medial facet?
repeated or sustained deep flexion.
What is the thickest cartilage in the body?
The thickest cartilage in the body is found in the knee complex (patellofemoral?) due to highest compression and shear forces on the body.
What is paradoxical knee extension?
Hamstring and gastroc finishing full extension of knee
What represents the pull of the quads?
The patellofemoral Q angle.
How is the patellofemoral Q angle measured?
First line goes from ASIS to center of the tibia. Second line goes from center of the patella to the tibial tuberosity. Then measure the angle.
What is the normal range for the patellofemoral Q angle?
5-15 degrees with a mean of 10 degrees.
What are the normal ranges for the patellofemoral Q angle for adult men and women?
Males- 8-10 degrees. Females- 10-12 degrees.
What does the patellofemoral Q angle affects?
The tendency of the patella to track laterally.
What does a larger Q angle lead to?
greater outward pull on patella (more lateral tracking of patella)
What affects the Q angle more, height or by the configuration of the pelvis?
Height therefore on average men have less of a Q angle because they are taller than the average woman
What is the patellofemoral ratio?
A ratio of distance; tibial tuberosity to patellar apex (inferior pole)/ height of the Patella (Patellar apex to base.)
What is a normal patellofemoral ratio?
one.
When would the patellofemoral ratio be considered low and what is this known as?
less than 0.8 aka Baja (the patella is too low/ patella tendon is too short)
When would the patellofemoral ratio be considered high and what is this known as?
More than 1.2 and this is aka alta. (the patella is too high or the length of tendon is too great or patella is too small)
What will a Warberg, magna and parva patella mean?
Warberg- too wedge shaped. Magna- too large. Parva- too small.
What will functionally increase and decrease the patellofemoral Q angle?
Increase- lateral/external rotation of the tibia. Decrease- medial/internal rotation of the tibia.
What will excessive foot flare do to the Q angle?
Increase the Q angle and lead to an unstable patella.
When will the patella be less stable with extension or flexion? Why?
Less stable with extension. Due to shallower groove.
What muscle was mentioned that if weak will make the patella less stable?
VMO. Also mentioned the medial retinaculum.
Will genu vagum or varum make the patella less stable?
Valgum.
What is the function of the VMO?
Holds the patella medially (stretched medial retinaculum can be from MCL sprain)
What muscle was mentioned that if too tight will make the patella less stable?
Vastus lateralis or ITB.
What shapes of the patella will make it less stable?
Too small or facet angle is too flat.
Will patella baja or alta make the patella less stable?
Alta.
What rotation of the tibia will make the patella less stable?
Externally rotated.
What foot position will make the patella less stable?
Pronation.
What position of the knee will make the patella more stable? Why?
Flexed knee. Due to deeper groove and increased compression force.
What muscle if strong will make the patella more stable?
VMO.
What will genu varum do to patellar stability?
Increase it.
What patellar shapes will increase patellar stability?
Normal, large lateral lip.
What will patella baja do to patellar stability?
Increase it but wil lead to increase wear and tear due to excessive compression.
What foot position will make the patella more stable?
Normal or under pronated.
Where is the thickest cartilage in the body found?
Patellofemoral joint
What type of large force is placed on the patellofemoral joint?
Compression.
Cartilage compression of the patellofemoral joint will increase with what knee position?
Flexion.
What will the comprssion forces be like on the patellofemoral joint with; walking, joggin, stair climbing (walking), Descending stairs (walking), 90 degree squat?
Walking- half of BW, jogging- 4 X BW, Stair climbing- 2.5 X BW, descending stairs- 3.5 X BW, 90 degree- 7.5 BW.
What will the compression forces on the patellofemoral joint be like with jumping?
10 X BW.
What are the compression forces on the patellofemoral joint like with full extension of the knee?
No compression force through this joint.
During flexion of the knee what direction will the patella travel?
It glides inferior and posterior in the patellar sulcus.
What part of the patella will contact the femur with; zero degrees of flexion, 20 degrees, 45 degrees, 90 degrees, 135 degrees?
zero- no direct contact, 20- distal or apex, 45- central, 90- proximal or base, 135- Lateral and medial part of patella.
How much will the extensor leverage of the patella increase with 90-120 degrees and 0-5 degrees flexion?
90-120- 13%. 0-5- 31%.
With a 5, 15, 30, 45, 75 degree squat how much of the body weight will the quadraceps be able to lift?
5- 30%. 15- 100%. 30- 200%. 45- 300%. 75- 500%.
Walking on a level surface produces _____ x BW on quadraceps tendon, jogging produces about ____ X BW on quadraceps tendon, and jumping produces about ____ X BW on Quadraceps tendon.
1, 5, more than 10.
What muscle would respond faster to tension and faster to stress the VMO or Vastus lateralus and why?
Tension- Vastus lateralus. Stress- VMO due to faster twitch.
What are the ligaments of the anterior compartment of the knee?
Medial and lateral retinaculum.
What will the medial and lateral retinaculum allow for with a quadraceps tendon injury?
Allow patient to still extend the knee.
What could cause a tear of the medial retincaulae of the knee?
Valgus sprains and patellar dislocations.
A medial retinacular tear would lead to what?
Lateral patellar instability.
What would a weak or stretched medial retinaculum or a tight lateral retinaculum cause?
Lateral patellar tracking.
Where will the ITB be located at and what compartment of the knee?
Lateral knee and is included in the anterior compartment.
What are the 2 parts to the ITB and where will it insert at?
Smaller patellar band, larger tibial band, and inserts on patella and Gerdy’s tubercle.
What would happen with a tight ITB?
Rubs on the lateral epicondyle of the femur and pulls on the patella. Leading to lateral tracking dysfunction.
What is a lateral release of the ITB?
CUT ITB and or lateral retincaulum leading to decreased tension on lateral patella.
What are synovial plica?
Remnant of 3 embryotic parts of the knee that if they remain can cause recurrent snapping and pain in the knee.
What are most synovial plica like?
Small and asymptomatic.
Which synovial plica is the most common?
Medial plica
What causes the growth of synovial plica?
Synovial membrane is innervated and therefore an increased inflammatory cycle which can cause scarring and progressive growth at the plica
What should be done with synovial plica?
No pain then leave alone, but if there is pain then they should be checked out.
What are the menisci made of?
Fibrocartilagenous.
How will the menisci help the joint articulation to fit?
Deepen socket and increases stability and congruency. Allow for flexible socket and this accommodates the egg shaped femoral condyles.
The menisci accommodate what type of movement? Why?
Slide which decreases shear
How will the menisci help reduce compression?
Force is directed to peripheray away from articular surfaces.
How much of the compressive load will the lateral and medial menisci direct to the periphery?
Lateral- 70%. Medial- 50%.
With a partial and a total meniscectomy how much wear and tear increase will occur?
Partial- 50-60% increase in wear and tear. Total- 200-235% increase.
What are the shapes of the lateral and medial meniscus?
Lateral- o shaped. Medial- C shaped.
What are the designs of the lateral and medial meniscus and which one is injured most often?
Medial- skinnier, thinner, more fixed and is injured most often. Lateral- Stronger, more mobile and only about 25% of meniscus tears happen in the lateral menisci.
What part ot the medial menisci will tear the most often?
The posterior horn.
Where will the coronary ligaments attach to?
Inferior- tibia and menisci. Superior femur and menisci.
Name the other attachments of the menisic besides the coronary ligaments?
Medial collateral ligament (meniscus to Intercondylar area), intermeniscal ligament, posterior meniscofemoral ligament, anterior meniscofemoral ligament, popliteus (to lateral meniscus), semimembranosus.
What is another name for the posterior meniscofemoral ligament and what is its purpose?
Wrisberg and it stabilizes the posterior horn.
What is another name for the anterior meniscofemoral ligament and what is its purpose?
AKA humphry and I donˍ脌 know its purpose but it is rare.
What part of the menisci will the popliteus and semimembranosus attach to?
Popliteus- lateral meniscus. Semimembranosus- medial meniscus.
What happens to the menisci with flexion of the knee?
They slide posterior.
Which menisci will slide posterior the most with knee flexion and why?
Lateral because it is not attached to the Lateral collateral ligament.
When flexed at the knee where will the focal weight bearing be at?
The posterior horn.
Deep squats (over 90 degrees) will increase stress where?
Posterior horns.
What happens to the synovial fluid of the knee joint complex when the knee is flexed?
It is squeezed in a posterior direction.
What will support the posterior horn and the lateral meniscus?
Popliteus and meniscofemoral ligaments.
What happens to the menisci with knee extension?
They slide anterior.
Which menisci will slide anterior more with knee extension?
Lateral always
Which menisci will deforme more with knee extension and why?
Medial because it is attached to the medial collateral ligament.
What position is the knee in while fully extended?
Tight packed.
What is the pressure on the menisici like with full extension?
More spread out so pressure is less.
What happens to the synovial fluid of the knee joint complex when the knee is extended?
It shifts anterior.
What motions can damage the meniscus?
Rotation, Flexion, Extension, Lateral Bending
What does the menisci move with knee rotation?
With the femur and opposite the tibia.
What happens to the medial menisci with internal rotation?
Medial- rotates anterior and is more prominent in anterior part of the medial joint line.
What happens to the lateral menisci with internal rotation?
Lateral- moves posterior and deepr within the joint thus the lateral joint line deepens. MORE PRESSURE IS EXERTED ON THE MEDIAL MENISCUS WITH INTERNAL ROTATION.
What happens to the medial menisci with external rotation?
Medial- joint deepens. PRODUCES MORE PRESSURE ON THE LATERAL MENISCUS.
What happens to the lateral menisci with external rotation?
Lateral- rotates anterior into the anterolateral joint line.
Abnormal movements of the menisci with fixation leads to what?
Meniscal tears.
How can you prevent abnormal movements of the menisci with fixation?
Adjustments.
What is the stress test that will test for movements/changes with VARUS and VALGUS?
Bohlers test.
How is VARUS tested?
Pinches medial meniscus and tractions lateral meniscus thru coronary ligaments.
How is the VALGUS test done?
Pinches lateral meniscus and tractions medial meniscus thru medial collateral and coronary ligaments.
The potential for injury with the menisci is with what movement?
Any movement and creates a snap (type of crepitus)
What are the common mechanisms of injury for the menisci?
Deep flexion, hyperextension, external rotation and valgus stress.
What other conditions can cause symptoms to be similar to a meniscus tear?
Plica can be similar in presentation (snapping crepitus and edema)
What is the old unhappy triad?
A severe knee injury involving damge to the medial meniscus, ACL, and MCL.
What is the new unhappy triad?
A severe knee injury involving damge to the medial meniscus, ACL, and LCL.
What is the healing of menisci like?
Poor healers since they are made of fibrocartilage and are mostly avascular.
What is the blood flow like to the menisci?
Mainly avascular besides the outer 1/3 in young and healthy. If older and not healthy the outer menisci is more fibrous.
Where will nutrients for the menisci come from?
Synovial fluid.
What part of the menisci is most poorly supplied with blood?
Central portions especially the posterior horns.
What is the innervation of the menisci like?
Outer part of meniscus with pain and proprioception @ junction with deep capsule.
What happens to the menisci with age?
decreased vascularization, increased wear and tear, increased friability.
Name the two collateral ligaments and both of their names?
Medial collateral ligament (MCL) aka tibial collateral ligament (TCL), Lateral collateral ligament (LCL) aka Fibular collateral ligament (FCL).
What ligament is posterior to the LCL?
Poplitiofibular ligament (PFL).
Where will the LCL attach to?
Lateral femoral epicondyle and fibular head.
The LCL primarily resists what?
Varus stress.
what are the 2 sprain mechanisms of the LCL?
Large varus stress and hyperextension.
Where will the MCL attach to?
Medial femoral epicondyle and medial tibial condyle and shaft.
What does the MCL primarily resist?
Valgus stress.
What are the 2 sprain mechanismis of the MCL?
Valgus stess and hyperextension.
Which ligament is larger the LCL or MCL?
Medial is larger.
Which ligament is damaged more the LCL or MCL?
MCL.
What will medial and lateral rotation do to the collateral ligaments?
medial- decreases tension on them. Lateral- increases tension on them.
Which rotation, medial or lateral, allows for conjoint rotation?
Medial rotation allows conjoint medial rotation of tibial rotation that must accompany flexion
If the collaterals limit medial rotation what action of the foot would it interfere with?
Decreased internal tibial rotation leads to decreased pronation
What are the 3 parts to the posteromedial capsular complex of the knee?
- Posterior part of MCL. 2. Semimembranosis tendon and tendon expansion. 3. Oblique popliteal ligament.
What will the posteromedial capsular complex of the knee resist?
Hyperextension, anterior translation, valgus stress, extremes of lateral tibial rotation.
Name the 5 parts of the posterolateral capsular complex of the knee?
- Popliteofibular ligament. 2. LCL. 3. Arcuate ligament. 4. biceps femoris tendon and tendon expansion. 5. Popliteus.
What will the posterolateral capsular complex of the knee resist?
anterior translation, hyperextension, varus stress, medial rotation and lateral rotation extremes.
How is the posterolateral capsular complex of the knee palpated?
In a figure 4 pattern.
What happens to the posterolateral capsular complex of the knee during knee flexion?
LCL- lax, PFL- tense.
What will happen when the LCL is lax?
This allows the tibia to undergo its normal internal rotation(conjoint rotation).
What will happen when the PFL becomes tense?
It doesnˍ脌 interfere with internal rotation; half as strong as the LCL.
What is more resistant to anterior translation stability the LCL or PFL?
PFL.
What is the order of ligament failure with increased carus stress?
LCL—> PFL—-> popliteus and acruate ligaments.
Which ligament the PFL or LCL is more resistant to anterior translation?
PFL is more resistant to anterior translation
What are the 2 cruciate ligaments?
ACL and PCL.
Where are the cruciate ligaments found at in general?
Intracapsular and extrasynovial (outer lining by synovial membrane).
What is the blood supply like to the cruciate ligaments?
they are relatively hypovascular however the synovial lining is highly vascular.
What is the significance of a highly vascular synovial lining of the cruciate ligaments?
If the ligaments rupture then bleeding would occure and this is calle dhemarthrosis.
Where will the anterior cruciate ligament attach to?
anterior tibial plateau and anterior tibial spine to the medial aspect of the lateral femoral condyle.
Which cruciate ligament is largest?
Posterior is largest.
What are the parts of the ACL?
- Anterior band. 2. Posterior band.
What will the tension be like on the ACL during different positions?
Always tense. Since the anterior band is tense when knee is flexed and posterior band is tense when knee is extended.
The ACL is primaraly resistint to what?
anterior tibial translation.
Why will 3/4 of all knee hemarthrosis involve the ACL?
Because it supports the blood vessels of the femur.
What is the name of the test for tibial translation joint play?
Anterior drawer test.
Why are there so many ACL injuries in female athletes?
When running, cutting and jumping, girls exhibit less upper body strength and control
What muscles do females rely on for deceleration of the lower extremity?
Females rely more on quadriceps (increases tension on ACL) rather than hamstring, gluteal and calf muscles. Also, females are more likely to land from a jump with the knees in a genu valgum position
What is the most common ligamentous problem?
MCL Sprain
Where will the PCL attach to?
Attaches to the lateral aspect of medial femoral condyle to posterio proximal tibia (NOT TO THE TIBIAL PLATEAU).
The PCL crosses _______ to the ACL.
Posteromedial.
Which ligament is stronger the ACL or PCL and by how much?
PCL is 2X as strong as ACL.
The PCL is also always tense but it is least tense when?
with 25-40 degrees flexion.
What are the parts of the PCL?
smaller anterior and larger posterior bands.
The PCL is primarily resistant to what?
Posterior translation.
What is the gravity sag sign and what will it mean?
It is posterior sagging of tibia when supine/ knee bent postion and it is a tear of the PCL.
What is the most serious ligmaentous injury of the knee?
ACL.
Which Cruciate ligament will be less likely to require corrective surgery when torn?
PCL.
What muscle protects the PCL?
Quadriceps
What muscle protects the ACL?
Hamstrings
Why will the PCL be less likely to requrie surgery if torn?
Massive contribution of quadraceps.
What is the test for posterior tibial translation joint play?
Posterior drawer test.
When will the cruciate ligaments twist around each other and then when will they untwist?
Twist- internal rotation. Untwist- external rotation.
During what rotation is sthe ACL weaker and more likely to tear?
During internal rotation
What motion of the foot can lead to increased twisting and eventual ACL failure?
Increased pronation of the foot
Injury to the ACL increases pronation and this leads to what?
Increased twisting and increased stress.
What is the secondary stabilizers of the knee?
Dynamic stability of muscle contractions.
What will happen to the knee with isometric contraciton during a sustained squat?
about 60% decrease in rotational laxity and about 300% increase in joint stiffness.
What is the difference between closed and open chain with the knee complex?
Closed- increases co-contraction compared with open chain (increased velocity —> increased con-contraction of antagonists).
What three muscle groups need to be balanced for a stable knee complex?
Quads - hams, medial tibial rotators (pes answerine/popliteus) and lateral tibial rotators (ITB/biceps)
what is the difference between quads and hams with slow and fast contraction?
Q:H slow 60:40. Fast- 10:9
What muscle is most importatn to the patellar stability?
VMO.
What muscle is reflexivley faster the VMO or the VL?
VMO.
Which muscle will atrophy faster the VMO or the VL?
VMO.
What is the priamry and seconary stabilizer for anterior translation?
1- ACL, PFL. 2- hams and ITB.
What is the priamry and seconary stabilizer for posterior translation?
1- PCL, s -quads and popliteus.
What is the priamry and seconary stabilizer for valgus?
1- MCL. 2- Medial retinaculum, poplteus, medial hams and pes anserine.
What is the priamry and seconary stabilizer for varus?
1- LCL. 2- lateral retinaculum, ITB, and biceps tendon.
What is the priamry and seconary stabilizer for flexion?
1- PCL (anterior bundle) 2 - quadraceps (no ligaments).
What is the priamry and seconary stabilizer for extension?
1- ALL and cruciate ligaments. 2- hams, gastroc, popliteus.
What is the priamry and seconary stabilizer for medial rotation?
1- cruciates and posterior capsule. 2- lateral retinaculum, ITB, Biceps tendon.
What is the priamry and seconary stabilizer for lateral rotation?
1- collaterals and posteriomedial capsule. 2- medial retinaculum, poplieus, medial hams and pes anserine.
Damage to the ACL and lateral complex will lead to what type of instability?
Anterolateral rotational.
Damage to the ACL and medial complex will lead to what type of instability?
Anteromedial rotational.
Damage to the PCL and lateral complex will lead to what type of instability?
Posteriolateral rotational.
Damge to the PCL and medial complex will lead to what type of instability?
Posteromedial rotational.
What are the bursae found within the joint cavity?
1) Suprapateller bursa 2) Popliteal bursa 3) gastrocnemius bursa
What is a baker’s cyst?
Swollen posterior bursa
What other bursae of the knee are not connected to the joint cavity?
1) Prepatellar 2) infrapatellar 3) pes answerine 4) ITB
How is fluid moved within the joint cavity and bursae?
Fluid movement occurs with flexion and extension
Where is the hip joint found?
Between the acetabulum and the femoral head.
The hip joint in general is unstable in who?
Infants especially female and northern european infants.
What % of congenital hip dislocations are female?
90%.
What are the 3 parts of the acetabulum and where are they located at?
Ilium- superior, Iscium (posteroinferior), pubis- anteroinferior.
What is the difference between the acetabular brim and notch?
The brim is 4/5 of a full circle and the notch encloses the anteroinferior 1/5.
What is the thickest cartilage of the hip joint?
The superior semilunar cartilage because it is the main weight bearing region.
What are the other cartilage of the hip joint (besides the superior semilunar cartilage)?
Labrum and trans. Ligament.
Where will the labrum and transverse ligament be at and what are they made of?
Labrum- upper 4/5 of ring. Transverse ligament- the inferior part that covers the notch. Both are made of fibrocartilage.
What is the anteversion angle like for the acetabulum in males vs. females and infants?
Larger angle for females. Infants- more anterverted than adults.
Increased anterversion of the acetabulum will do what?
Decrease stability.
What will inferior acetabular tilt be like for males vs. females, and adults vs. infants?
Males larger than females. Adults greater than infants.
Increased inferior tilit of the acetabulum will do what?
Increase stability as it puts a greater cap over top of the hip
What is the shape of the femur head?
2/3 sphere and larger in diameter thatn the acetabulum @ labrum.
What are the 2 keeper rings?
Labrum and zona orbicularis of the capsule.
What is the articular cartilage of the femur head like?
Thickest superior since all pressure is here.
Where is proximal physis of the femur located at and this causes what?
It is proximal to the neck and this creates a lot of shear force as we grow.
When will a slipped capital femoral epiphysis be seen?
Slipped capital femoral epiphysis happens d/t increased growth and shear In early teens and tall and large people. More common in males.
What does trochanter mean?
To turn.
During growth what normally happens to the distal femur?
twisted medially relative to the proximal end.
What is the normal, anterverted and retroverted angles of the femoral torsion?
Normal- 10-20 degrees. Anteverted- >20degrees. Retroverted- <10 degrees.
What will make the hip more and less stable anterverison or retroversion?
Anterversion- less stable. Retroversion- more stable.
What is femoral inclination?
Draw a line directly through the center of the fovea capitis femoris. Then draw another line parallel to the long shaft of the femur and then measure the inside angle
What is the normal femoral inclination angle?
120-130 degrees.
What will femoral inclination angles of >130 and <120 mean?
> 130- coxa valga- less stable hip. <120- coxa vara- more stable hip.
What is the femoral inclination angle like at birth?
150 degrees.
Coxa vara is often seen in who?
The elderly.
Coxa vara will make the hip more stable, but what is the negative trade off to coxa vara?
More shear stress on femoral neck increases the risk of fracture.
Both coxa vara and valga cause what?
Abnormal wear and tear on articular surfaces and may lead to osteoarthrosis.
Will increased abductor or adductor strength make the hip joint more or less stable?
Increased abductor- increases stability. Increased adductor- less stable.
Will extension, external rotation and abduction make the hip joint more stable?
yes.
Will flexion, internal rotation, and adducted position make the hip joint more stable?
No it makes it unstable.
Will increased or decreased acetabular anteversion favor hip joint stability?
Decreased acetabular anteversion
Will increased or decreased inferior acetabular tilt favor hip joint stability?
Increased inferior acetabular tilt
Will femoral anteversion or retroverion favor hip joint stability?
Femoral Retroversion
Will coxa vara or coxa valga favor hip joint stability?
Coxa Vara
Will a male (android pelvis) or female (gynecoid pelvis) favor hip joint stability?
Male/android pelvis
Will being an adult or infant favor hip joint stability?
Adult
What are the 3 types of femoral trabeculae?
- vertical- compression on femoral head. 2. Acruate- bending of neck. 3. Intertrochanteric- torsion between trochanters.
What happens to the femoral trabeculae with age?
Vertical trabelculae are saved and others are depleted in osteoporosis.
Loss of the arcuate and intertrochanteric trabeculae in elderly leads to what?
Femoral neck fracutures in the weak cortical zone.
Pelvic trabeculae direct forces from acetabulum to where?
SI.
What is gynecoid?
Like a women.
What are gynecoid pelvic lines of stress like?
Larger oval outlet.
What are android pelvic lines of stress like?
Smaller heart haped outlet.
What are the lines of force transfer like for the pelvic lines of stress while sitting and standing?
Sitting- ischium —> SI joint and sacrum. Standing- femur —-> SI joint and sacrum.
What are hip joint ligaments like?
Very strong.
How many tight packed positions of the hip are there?
Two and it is one of the most stable joints in adults.
What are the two tight packed positions of the hip?
Figure 4 (extended, adducted, internally rotated) and Flexed, internally rotated and adducted position in side posture
Why are the ligaments of the hip joint relatively unstable in infants?
Because of the ligaments being lax from relaxin from mom
What is the shape of the iliofemoral ligament and it is aka?
Y and aka ligament of bigalow.
What is the hip ligament that is not structurally significant and why is it there?
Ligamentum teres and it mainly supports Blood vessels.
Which hip ligament is the strongest?
Y-ligament aka iliofemoral ligament aka ligament of bigalow.
