Flashcards in Joints of Lower Limb Deck (37):
What covers opposing bony surfaces in synovial joints?
Hyaline (articular) cartilage
What surrounds synovial joints?
A fibrous capsule
Give the movements of the hip and the range of motion (in degrees) for each movement
Flexion (120), Extension (15), Abduction (45), Adduction (45), Medial/Internal Rotation (30), Lateral/External Rotation (50), Circumduction
What are the intra-articular ligaments of the hip and what does each do?
Ligamentum teres (ligament of femur head, transmits branch of obturator artery), Transverse Acetabular Ligament (bridges acetabular notch)
The round ligament of the femur head (ligamentum teres) connects what two structures?
Femur head to acetabular notch
What ligament can still support you briefly even with little muscle involvement (e.g. in lower limb paralysis)?
The iliofemoral ligament
List the extra-articular ligaments of the hip joint
Iliofemoral (inverted Y) ligament, Pubofemoral ligament, Ischiofemoral ligament
What does the iliofemoral ligament do and what shape is it?
Limits hip extension, lateral rotation, and keeps you upright. It is inverted Y shaped
What does the pubofemoral ligament do?
Limits extension and abduction
What does the ischofemoral ligament do?
Limits hip extension and medial rotation
What are the components of the FABER test and what does it test for?
Flexion, ABduction, External Rotation. It tests for a tight hip joint capsule
Where are the trochanteric bursae located and what do they do?
Between IT band and greater trochanter. They reduce friction in the hip joint
What might cause trochanteric bursitis?
A shortened IT band (increases friction in the hip joint, overworking the trochanteric bursae)
What test is done to look for a shortened IT band and briefly describe it
The Ober test. Lying on side with the leg in question behind you, it is attempted to lower the leg below the table. If you cannot lower it below the plane of the table, you have a shortened IT band
Where is the knee joint capsule deficient and why?
Posteriorly to allow for passage of the popliteus tendon
Give the motions of the knee joint and the range of motion (in degrees) for each
Flexion (130), Extension (0-15), Medial rotation (20-30), Lateral rotation (30-40)
Are the cruciate ligaments intra or extra -capsular? Are the intra or extra -synovial?
Intracapsular but extrasynovial
What does the ACL do?
Limits extension of the knee, limits anterior tibial translation, limits medial rotation of the knee
What test is used to check the integrity of the ACL?
The Lachman test
Which is stronger and thicker, the ACL or the PCL?
The PCL is 50 percent stronger and thicker than the ACL
If the tibia drops when you sit with your knee up, this is a sign of deficiency in what structure?
What are the menisci comprised of and what is their function?
They are fibrocartilagenous discs. They 1) Increase contact area and stability, 2) Absorb shock, 3) Aid in joint lubrication
Which parts of the menisci have blood supply, what is the blood supply there, and how does the rest get nutritional supply?
Outer third supplied by genicular arteries, inner two thirds gets nutrition from synovial fluid (wont heal if torn, consider menistectomy if torn)
What attaches the menisci anteriorly?
The transverse ligament of the knee
What attaches the menisci to the capsule?
Coronary ligament and the anterior/posterior horns
What test is used to check for injury of the meniscus?
The McMurray test
Is the popliteus muscle superficial or deep to the arcuate ligament?
Deep to the arcuate ligament
What is the unhappy triad and why are they called this?
The tibial collateral ligament (MCL), the medial meniscus, and the anterior cruciate ligament (ACL). They are commonly injured together
What is contained within bursae?
List the three major bursae within the knee
Suprapatellar bursa (communicates with knee capsule), Pre-patellar bursa (Housemaids syndrome), Infrapatellar bursa (superficial and deep). There are also many others
What type of bone is the patella?
A sesamoid bone
What is the primary function of the patella?
To increase the mechanical advantage of the quadriceps femoris muscles during knee extension
What bones participate in the ankle joint?
Talus, fibula, tibia
Which movement of the foot is more stable and why, dorsiflexion or plantarflexion?
Dorsiflexion, because the talus is wider anteriorly
Movements of the ankle joint and range of motion (in degrees) of each
Dorsiflexion (12-15), Plantarflexion (55), some rotation when plantarflexed
Most injuries of the ankle are the result of what type of movement and injure what structure?
Forced inversion/plantarflexion, cause injury to anterior talofibular ligament