Knee & Hip Joint Flashcards
The hip joint is an articulation between the femoral head and the acetabulum of the pelvis. What type of joint is it?
Ball-and-socket
***Inherently stable
Acetabulum means “Little vinegar cup” in latin, and is formed by the fusion of what?
Ilium
Ischium
Pubis
The acetabulum begins as triradiate cartilage, with the fusion process occurring during what ages?
15-25 yo
This is the ligament that bridges the acetabular notch.
Transverse Acetabular Ligament
The femoral head forms 2/3 of a sphere with over ______ percent of it within the acetabulum.
50
What is the femoral head mostly covered with?
Articular cartilage (except fovea)
This is a dense, vertically oriented bone in the posteromedial aspect of the proximal femur (inside of the femur).
Calcar Femorale
This ligament is “Y-shaped” and extends from the AIIS to the Intertrochanteric Line. Sometimes considered the “strongest ligament in the body”.
Iliofemoral Ligament
The Iliofemoral Ligament prevents what?
Hyperextension
This ligament extends from the Obturator Crest to the Intertrochanteric Line. It blends laterally with the Iliofemoral Ligament.
Pubofemoral Ligament
What is the purpose of the Pubofemoral Ligament?
Primarily prevents hyperabduction
Prevents hyperextension
This ligament extends from the Ischial component of the Acetabular Rim to the Femoral Neck. It does NOT reach the Intertrochanteric Crest.
Ischiofemoral Ligament
T/F. The posterior capsule of the hip does not extend as far lateral as the anterior capsule.
True
This is the weakest of all the hip ligaments, but is balanced by robust external rotators. This is why posterior hip dislocations are most likely!
Ischiofemoral Ligament
This ligament stretches from the Acetabular Notch/Transverse Acetabular Ligament to the Fovea of the Femur.
Ligament of Head of Femur
In the Ligament of Head of Femur, there is a synovial fold conducting an artery to the head of the the Femur. Where does this artery come from?
Obturator A.
T/F. The Ligament of Head of Femur provides a large amount of stability to the Femoral Head.
False. It provides minimal stability.
This is the fibrocartilaginous rim that goes to the margin of the Acetabulum. It increases the Acetabular articular area by 10 percent.
Acetabular Labrum
This ligament is a continuation of the Labrum inferiorly and courses over the Acetabular Notch.
Transverse Acetabular Ligament
The Labrum and Transverse Acetabular Ligament contribute to ________ for the hip joint.
Stability
What arteries supply the Femoral Head and Neck?
Medial Circumflex Femoral A.
– Retinacular As.
Lateral Circumflex Femoral A.
- Ascending Branch
- Transverse Branch
Obturator A.
– Acetabular Branch (**this one goes through ligament)
The Acetabular Branch of the Obturator A. contributes to the Femoral Head at birth but diminishes by what age?
4 yo
The (LATERAL/MEDIAL) Circumflex Femoral A. courses underneath the Iliofemoral Ligament and capsule posteriorly.
Medial
The (LATERAL/MEDIAL) Circumflex Femoral A. pierces the Iliofemoral Ligament.
Lateral
What is Hilton’s Law?
Nerves supplying muscles directly overlying and acting at joint also innervate that joint.
This is the strongest flexor of the hip.
Iliopsoas M.
What muscles are affected in Trendelenberg gait?
Gluteus Medius M.
Gluteus Minimus M.
This special test assesses for labral pathology. The physician places the patients hip into flexion at 90 degrees, adduction, and internal rotation. Positive if there is groin pain.
FADIR
This special test assesses for hip pain or posterior SI pain. The physician puts the patient’s hip into flexion, abduction, and external rotation. Positive with pain and limited motion.
FABER (Patrick’s)
This special test helps with indeterminate radiographs in possible hip fractures. The patient lies supine, and the physician internally and externally rotates their leg. Positive is pain.
Log Roll
This special test assesses for flexion contracture of the hip. The patient lies supine and drops their contralateral leg off the table and pulls the tested leg to their chest. Positive of the contralateral thigh raises off the table.
Thomas Test
This special test is performed by having the patient lay lateral recumbent with the affected side up. The physician extends hip/flexes knee and allows it to drop. Positive test is the affected leg not passing neutral adduction.
Ober’s Test
This special test is helpful with intraarticular pathology, particularly OA. The patient lies supine and resists hip flexion with a straight leg at 45 degrees. Positive test is pain.
Stinchfield
A hip dislocation is considered an orthopedic emergency, especially in the (YOUNG/ELDERLY).
Young
A hip dislocation can be simple vs. complex. What makes it complex?
It is accompanied with an Acetabulum/Femur fracture
Which direction do hip dislocations go 90 percent of the time?
Posterior
The position of the hip at time of injury affects the direction of the dislocation and associated injuries. For example, a ________ hip is mored susceptible to dislocation because of capsular laxity.
Flexed
What is the resting position of a posterior hip location?
Slight flexion
Adduction
Internal rotation
Hip fractures have severe morbidly in the (YOUNG/ELDERLY).
Elderly
How many hip fractures occur every year?
150,000
***Over $10 billion
In a hip fracture, what is the presentation of the hip at rest?
Affected hip is shortened and externally rotated
The knee joint is less inherently stable than the hip and is most stable in extension. What type of joint is the knee?
Primarily hinge
***Also does pivot, glide, and rotate
What are the 3 compartments of the knee joint?
Medial femorotibial
Lateral femorotibial
Patellofemoral
In the distal Femur, the (MEDIAL/LATERAL) Condyle is larger.
Medial
What separates the two condyles of the Femur?
Intercondylar Notch
What comes off the condyles medially and laterally, and serve as attachments for collateral ligaments?
Medial Epicondyle
Lateral Epicondyle
This is by the Medial Epicondyle of the Femur and is the attachment point for the adductor muscles.
Adductor Tubercle
What does the Femur articulate with distally?
Meniscus
The relatively flat, superior articular surface of the Tibia is called what?
Tibial Plateau
The Tibia has proximal Medial and Lateral Condyles that flare out. The Medial Condyle is (CONVEX/CONCAVE) and the Lateral Condyle is (CONVEX/CONCAVE).
Concave
Convex
The Intercondylar area of the Tibial Plateau contains what?
Medial and Lateral Eminences
***Collectively called Intercondylar Eminence
This is the largest sesamoid bone in the body and provides mechanical advantage for the quadriceps.
Patella
3/4 of the Patellar body is covered by…
Articular cartilage (thickest in the body of Patella)
The Patella has a Medial and Lateral Facet, with the ________ being larger.
Lateral
***Medial is more rounded
This is a failure of the superolateral portion of the Patella to fuse. It’s commonly mistaken for a fracture, and occurs in 8 percent of the population with over having being bilateral.
Bipartite Patella
This ligament is extracapsular, and stretches from the Lateral Epicondyle of the Femur to the Fibular Head. It inserts along with the Biceps Femoris M and is cord-like.
Lateral Collateral Ligament (LCL)
***Also called Fibular Collateral Ligament
What muscle tendon passes deep to the LCL?
Popliteus M. tendon
The LCL resists (VARUS/VALGUS) stress.
Varus
This ligament has a variable original at the Lateral Femoral Epicondyle to the Tibia posteriorly to Gerdy’s Tubercle. It is flatter than the LCL and runs just proximal to it. It helps with rotational stability of the knee.
Anterolateral Ligament (ALL)
This fracture occurs when the ALL is avulsed from the Tibial insertion. If this occurs, it often means the ACL was also ruptured.
Segond fracture
This ligament is capsular and can be superficial and deep. Superficially, it stretches from the Medial Femoral Epicondyle to the proximal Tibia and lies deep and posterior to the Pes Anserinus.
Medial Collateral Ligament (MCL)
***Also called Tibial Collateral Ligament
This ligament, when running deep, is part of the joint capsule and helps form the meniscofemoral/meniscotibial ligaments. Provides meniscal attachment.
Medial Collateral Ligament (MCL)
The superficial aspect of the MCL resists (VARUS/VALGUS) stress.
Valgus
Is the LCL or MCL stronger?
LCL
This optimizes force transmission across the knee. It helps with shock absorption and increases congruency.
Meniscus
The Meniscus is a secondary stabilizer of the knee, but becomes the primary stabilizer in the event of an ______ deficiency.
ACL
The Meniscus is “C-shaped” medially and “circular-shaped” laterally. They are interconnected via what ligament?
Intermeniscal Ligament
The Meniscus are peripherally attached to the capsule by what ligaments?
Coronary Ligaments
What ligaments attach the Meniscus to the Femur?
Meniscofemoral Ligaments
This ligament stretches from the Lateral Intercondylar ridge to the anterior Tibia, between the Intercondylar Eminences.
Anterior Cruciate Ligament (ACL)
The ACL has two bundles, which are…
Anteromedial
Posterolateral
The Anteromedial ACL bundle is tightest in (FLEXION/EXTENSION) while the Posterolateral ACL bundle is tightest in (FLEXION/EXTENSION).
Flexion
Extension
This ligament stretches from the posterior Tibial sulcus below the articular surface to the anterolateral Medial Femoral Condyle.
Posterior Cruciate Ligament (PCL)
The PCL has two bundles, which are…
Anterolateral
Posteromedial
The Anterolateral PCL bundle is tightest in (FLEXION/EXTENSION) while the Posteromedial PCL bundle is tightest in (FLEXION/EXTENSION).
Flexion
Extension
What provides blood supply to the knee joint?
Genicular Anastomosis —–
- Femoral A.
- Popliteal A.
- Anterior Recurrent branch of Anterior Tibial A.
- Posterior Recurrent branch of Anterior Tibial A.
- Circumflex Fibular A.
What are the “cruciate” ligaments of the knee?
ACL
PCL
This artery supplies the cruciate ligaments, synovium, and posterior horns of the Meniscus.
Middle Genicular A.
This artery supplies the peripheral 25 percent of the Medial Meniscus.
Inferior Medial Genicular A.
This artery supplies the peripheral 25 percent of the Lateral Meniscus.
Inferior Lateral Genicular A.
What provides innervation to the knee?
Femoral N. – anterior
Common Fibular N. – lateral
Tibial N. – posterior
Obturator/Saphenous N. – medial
Explain what happens to the Femur when the knee is flexed.
It posteriorly rolls backward on the articular surface of the Tibia. The center of rotation moves posteriorly.
In the last 15 degrees of knee extension, what does the Tibia do and why?
Externally rotates 5 degrees, because it allows the cruciate ligaments to tighten and decrease work on quadriceps while standing.
This muscle “unlocks” the Tibia by internally rotating it to initiate flexion.
Popliteus M.
What is the term for “bowed legs”?
Genu Varum
What is the term for “knock knees”?
Genu Valgum
What is the term for “back knee”?
Genu Recurvatum
What are the “grades” of ligament of sprain?
Grade 1 – stretching and small tears
Grade 2 – larger tear
Grade 3 – complete rupture
How could you test for an LCL injury?
Varus stress test – brace medial knee and push leg towards midline
If positive, will have pain laterally
How could you test for an MCL injury?
Valgus stress test – brace lateral knee and push leg away from midline
If positive, will have pain medially
This knee injury occurs in 40 percent of all knee injuries. It is due to valgus stress in slight flexion and can occur from a blow to the lateral knee. Common in sports injuries.
MCL injury
***Much more common than LCL injury
What is the most common multi-ligament injury that occurs?
MCL
ACL
The O’Donoghue unhappy triad of knee injuries occurs with what ligaments?
ACL
MCL
Medial Meniscus
What is a preventative measure of athletes to reduce their chances of sustaining a knee injury?
Wearing prophylactic braces
This meniscal test has the patient lay prone with their knee flexed to 90. The physician loads axially through the flexed leg and rotates. Positive test is pain/click.
Apley Compression
This meniscal test has the patient stand on the affected leg at 20 degree knee flexion. The patient then rotates on the leg. Positive test is pain/click.
Thessaly test
This meniscal test has the physician place the patient into ER and valgus then flexion to extension for a lateral test. For a medial test, the patient is placed in IR and varus then to flexion and extension. Positive test is pain/click.
McMurray’s test
T/F. When a meniscal tear occurs, the ACL becomes stronger and provides more support for the knee.
False. When a meniscal tear occurs, there is increased risk in ACL deficiency.
The Meniscus has different zones based on their blood supply, which are important in the event of an injury. What are the zones and why are they important?
Red-Red zone
Red-White zone
White-White zone
They’re important because the injury location within a zone will determine if it can be repaired or if it needs to be resected.
In this PCL test, the patient lies supine with hips and knees flexed to 90. Physician then examine the posterior positioning of the Tibia relative to the distal femur.
Posterior sag
In this PCL test, the patient lies supine with hips and knees flexed to 90. The patient then fires their quad while immobilizing the foot. Positive test occurs if the Tibia reduces anteriorly.
Quadriceps Active test
This PCL test is the most accurate. Patient lies supine with hip and knee flexed to 90, while the physician posteriorly directs force on the proximal Tibia. Positive test is pain.
Posterior Drawer test
This ligament injury is very commonly undiagnosed and occurs in 5-20 percent of knee injuries.
PCL
This ACL test has the patient lie supine with hip and knee flexed to 90, while the physician anteriorly directs forces on the proximal Tibia. Positive test is pain.
Anterior Drawer test
In this ACL test, the patient lies supine while the physician stabilizes the distal femur and proximal tibia with each hand at 20 degrees. Physician then pulls Tibia anteriorly Positive test is pain, but be careful of false positive if the PCL is injured.
Lachman test
In this ACL test, the patient lies supine and must be fully relaxed. In extension, the proximal Tibia is internally rotated and valgus force is placed to sublux the lateral plateau anteriorly. The knee is then flexed and turns IT band into reduction force that forces Tibia back under distal femur.
Pivot Shift test
ACL tears are much more likely to occur in females, and increases the likelihood of developing ________ by 3-5x.
Arthritis
If a newborn has a hip dislocation, we worry about avascular necrosis. Which arterial supply is compromised by this?
Obturator A.
- **It’s this artery in babies that are 4 months or less old
- **After 4 months, it’s the Medial Femoral Circumflex A.
Which of the collateral ligaments of the knee is attached to its respective meniscus?
MCL attaches to Medial Meniscus
***LCL does NOT attach to Lateral Meniscus
These ligaments run in an “X-shape” along the posterior knee joint.
Oblique Popliteal Ligament
Arcuate Popliteal Ligament
The Oblique Popliteal Ligament comes off what muscle tendon?
Semimembranosus M. tendon
