Exam 1 Flashcards
Acetabular dysplasia
Shallow acetabulum
Coxa profunda
Acetabulum excessively covers the femoral head
Center angle or Angle of Wilburg
Normal is greater than 25
Normal angle for acetabular anteversion
Normal is 20 degrees
Functions of labrum
Deepens socket Increases concavity Enhances joint stability Decreases force transmission Provides proprioceptive feedback
How does femoral head face
Medially, superiorly, and anteriorly
Angle of inclination (description and normal angle)
Through the femoral head and neck and the longitudinal axis of the femoral shaft. Normal is 125
Angle of torsion (description and normal angle)
transverse plane between the axis of the femoral neck and the axis of the femoral condyles. Normal is 10-20
Anteversion angles
Angle of anterior torsion is greater than 15 to 20 degrees
Retroversion angle
Angle of anterior torsion is less than 15 to 20 degrees
Maximal contact of hip joint
Flexion, abduction, and ER
What does superior and inferior gluteal arteries supply
Capsule proximally and medially
What does lateral circumflex artery supply
Capsule distally
What does the medial femoral circumflex artery supply
Femoral head
Ligamentum Teres
Intra-capsular but extrasynovial
Passes under transverse acetabular ligament
Functions as a conduit for blood supply to the femoral head
Iliofemoral ligament
Limits medial and lateral roation
The inferior fibers abduct
The superior fibers adduct
Pubofemoral ligament
Limits lateral rotation in neutral
Resists hip abduction
Ischiofemoral ligament
Limits medial rotation regardless of hip position
Close packed position of hip
hip extension, slight abduction, and medial rotation
Position of comfort of the hip
moderate flexion, slight abduction, and midrotation
Medial trabecular system resists
compressive forces passing through hip joint
Lateral trabecular system resists
bending from parallel forces of the HAT and ground reaction forces
Hip flexion ROM (knee bent and extended)
Knee bent - 120
Flexed - 90
Hip extension ROM
30
Hip abduction ROM
45
Hip adduction ROM
20-30
Hip IR/ER
45
Functional requirements for gait
Flexion - 30
Extension - 10
Abduction/Adduction - 5
Medial/Lateral Rotation - 5
Posterior pelvis tilt
Hip extension
Anterior pelvis tilt
Hip flexion
Elevate pelvis
Wt bearing leg is in abduction
Drop pelvis
Wt bearing leg is in adduction
If hip moves forward
Wt bearing IR
If hip moves backward
Wt bearing ER
Greatest MA for gluteus maximus
Neutral
Greatest MA for extension for gluteus maximus
70 degrees of hip flexion
Greatest MA for hamstrings
Increases up to 35 degrees of hip flexion and then starts to decrease
Optimal length tension for hamstrings
90 degrees hip flexion and 90 degrees knee flexion
Anterior tilt force couples
Erector spinae and iliopsoas
Posterior tilt force couples
Hip extensors and abdominal muscles
CAM impinegement
Originates from pistol grip deformity of femoral neck (neck fails to taper as femoral head merges laterally into femoral neck)
Pincer impingement
Greater coverage or overhang of acetabulum on femoral head due to excessive retroversion of acetabulum and coxa profunda
Physiological axis
Femoral and tibial longitudinal axes form an angles medially at the knee joint of 180 to 185
Genu valgum (knock knees)
Medial tibiofemoral angles is greater than 185. Shifts compressive forces to lateral compartment
Genu varum (bow-legs)
Medial tibiofemoral angles is greater than 175 or less. Shifts compressive forces to medial compartment
Mechanical axis
From the center of the femoral head to the center of the talus
Function of menisci
Distribute weight bearing forces
Reduce friction between tibia and femur
Serve as shock absorber
Relieve joint stress
Overall function of knee ligaments
Excessive knee extension
Valgus and varus stresses of knee
A/P displacement of tibia beneath femur
Medial or lateral rotation of tibia beneath femur
Function of MCL
Resist valgus
Resist lateral tibial translation
Support ACL in resisting anterior translation of tibia on femur
Function of LCL
Resist varus
Resist lateral rotation of tibia on femur
Function of ACL
Anterior translation of tibia on femur
Limits hyperextension
Limits medial/lat rotation
Limits valgus/varus
Which muscles increase strain on ACL
Gastroc and quads
Which muscles decrease strain on ACL
Hamstrings and soleus
Posterolateral bundle of ACL
Taut in extension
Anteromedial bundle of ACL
Taut in flexion
Posteromedial bundle of PCL
Taut in full extension and again in deep knee flexion
Anterolateral bundle of PCL
Taut in 80 to 90 degrees of flexion
Function of PCL
Resist posterior translation of tibia on femur
Resist valgus/varus
Restrains and guides rotation of tibia
Posterior capsular ligaments
Oblique popliteal
Posterior oblique
Arcuate
Function of posterior capsular ligaments
Assist in checking hyperextension of knee
Check valgus/varus forces
Location of suprapaterllar bursae
Between quads tendon and anterior femur
Location of subpopliteal bursae
Between tendon of popliteus and lateral femoral condyle
Location of gastrocnemius bursae
Between tendon of medial head of gastroc and medial femoral condyle
Effects of removal of the meniscus
Contact area is decreased
Doubles the articular cartilage stress on the femur and multiplies the forces by six or seven times on the tibial plateau
Attachments of lateral meniscus
ACL
PCL
Meniscofemoral
Popliteus
Attachments of medial meniscus
ACL PCL MCL Capsule Semimembranosus
Knee flexion range in gait
60 to 70 degrees
Knee flexion range ascending stairs
80 degrees
Knee flexion range sitting down
90 degrees
Knee flexion during squatting
160
Maximum axial rotation is available to at…
90 degrees
Knee flexion is coupled with…..
Varus motion
Knee extension is coupled with…
Valgus motion
In non-weight bearing the tibia will rotate which way during the final degrees of knee extension
Laterally rotate
In non-weight bearing the tibia will rotate which way during the beginning of knee flexion
Medially rotate
In weight bearing the femur will rotate which way during the last 30 degrees of knee extension
Medially rotate
In weight bearing the femur will rotate which way to unlock for knee flexion
Laterally rotate
Parts of fibrous layer of knee
Extensor retinaculum
Medial and lateral patellofemoral
Medial and lateral patellomeniscal
Medial and lateral patellotibial
Attachments of iliofemoral ligament
AIIS to intertrochanteric line
Attachments of pubofemoral ligament
Pubic ramus to intertrochanteric fossa
Location of ischiofemoral ligament
Posterior capsule ligament that attaches to posterior surface of acetabular labrum
Origin and insertion of rectus femoris
AIIS and tibial tuberosity
OI of sartorious
ASIS and upper medial aspect of tibia
OIA of TFL
Originates on anterolateral lip of iliac crest and inserts into lateral condyle of tibia as IT band
Main function is to maintain function in IT band with glute max
OI of adductors
Body and inferior ramus of pubis and inserts into linea aspera
OI of gracilis
Symphysis pubis and pubic arch and inserts into medial surface of the shaft of the tibia
OI of glute max
Posterior sacrum and small portion of ilium
Superior fibers insert into IT band and inferior fibers insert into gluteal tuberosity
OI of glute med
Lateral surface of the wing of the ilium
Inserts into lateral and posterior superior portion of greater trochanter
OI of glute min
Outer surface of ilium
Inserts on the anterior portion of greater trochanter
OI of obturator internus
Inside of obturator foramen to greater trochanter
OI for obturator externus
External surface of obturator foramen and inserts into medial aspect of greater trochanter
OI of gemelli
Ischium to greater trochanter
OI of quadratus femoris
Ischial tuberosity to posterior femur between greater and lesser trochanter
OIA of piriformis
Anterior surface of sacrum to greater trochanter
Lateral rotator until hip is flexed to 90 then it becomes medial rotator
Attachments of superficial MCL
Medial femoral epicondyle to medial aspect of proximal tibia distal to pes anserine
Attachments of deep MCL
Inferior aspect of medial femoral condyle to proximal aspect of medial tibial plateau. Firmly attached to medial meniscus
Attachments of LCL
Lateral femoral condyle to fibular head where it joins with tendon of biceps femoris
Attachments of ACL
Lateral and anterior aspect of medial tibial plateau to posteromedial Aspect of lateral femoral condyle
Most common injury position of ACL
Knee slightly flexed and tibia is rotated in weight bearing
Attachments of PCL
Posterior tibial surface between the two horns of the menisci and insert into the lateral aspect of the medial femoral condyle
What muscle resists posterior translation of tibia if PCL is absent
Soleus
Attachments of meniscofemoral ligaments
Posterior horn of lateral meniscus and insert on the lateral aspect of medial femoral condyle
Anterior to PCL - Humphrey
Posterior to PCL - wrisberg
Excessive knee Hyperextension
Genu recurvatum
When is sartorious active in gait
Swing phase
Primary function of the popliteus
Medial rotator of tibia on femur (unlocking the knee)