Knee joint Flashcards
What are the articulations of the knee joint?
Patella and femur (trochlea surface)
Tibia and femur (condyles)
What kind of synovial joint is the articulation between the patella and the femur?
Saddle joint
What kind of synovial joint is the articulation between the femur and tibia?
Condylar joint
What factors contribute to knee joint stability?
- ligaments
- muscles and tendons
- iliotibial tract
Which part of the knee is the joint capsule most abundant?
The posterior aspect
On the femur, where does the joint capsule attach?
Posteriorly; intercondylar line
Laterally; encloses origin of popliteus/lateral epicondyle of femur
Anteriorly; deficient
What structure forms the ligamentum patellae
it’s an extension of quadriceps femoris tendon
Where does the ligamentum patellae attach?
Apex of patella and tibial tuberosity
State the tibial and femoral attachments of the medial collateral ligament.
Tibial; posteromedial to tibial tuberosity + membrane of semimembranosus
Femoral; medial epicondyle
True or false: The lateral collateral ligament is much thicker than the medial collateral ligament.
False. Medial collateral ligament is thicker.
Which collateral ligament is most likely to get damaged?
Medial collateral ligament.
Which cruciate ligament is more prone to injuries?
Anterior cruciate ligament
What does the anterior cruciate ligament do?
Prevent posterior dislocation of femur on tibia
Prevent anterior dislocation of tibia on femur
What are the functions of menisci?
- Shock absorbers; protect articular cartilage
- Lubrication of joint cavity
- Increase concativities of tibial femoral condylar joints
Which meniscus is more prone to injury?
the medial meniscus
State the most common cause of injury to the menisci.
Twisting strain of partially flexed knee.
What is valgus stress?
produced by a blow to the lateral side of the knee, often resulting in tearing of the tibial/medial collateral ligament
What is varus stress?
caused by a blow to the medial side of knee, often resulting in tearing of the lateral collateral ligament
Why is the medial meniscus often torn when the medial collateral ligament is torn?
Because the medial meniscus is firmly attached to the medial collateral ligament.
What nerve may be injured during a varus stress?
The fibular nerve
Describe knee valgus including symptoms, causes, and treatment.
Symptoms; knocking knees, knees angle away from midline of body
Causes; osteoarthritis of knee, damage to medial collateral ligament, damage to anterior cruciate ligament, damage to menisci
Treatment; exercises to strengthen thigh and hip muscles, osteotomy surgery
Which meniscus is more O shaped?
The lateral meniscus
Approximately how many bursae are around the knee joint?
About 12
Name the bursae of the knee joint.
Suprapatellar Prepatellar Infrapatellar Deep infrapatellar (*SPID) Brodie's bursa Bursa anserine
What is Housemaid’s knee?
Inflammation of prepatellar bursa
State how prepatellar bursitis is treated.
Resting the knee.
Using antibiotics if inflammation caused by bacteria.
Elevating knee
Cold compression
Compression using bandange
Aspiration by inserting needle into bursa
Surgery to remove the bursa in extreme cases (bursectomy)
What is arthroscopy?
a minimally invasive surgery procedure in which optic fiber placed in joint through an incision to visualize the structures and another incision is made so that special tools can be used to correct the problem
What is Clergyman’s knee?
Inflammation of infrapatellar bursa
What are the causes of Baker’s cyst?
Osteoarthritis or rheumatoid arthritis, which inflames the knee joint
Injury to the knee joint
Differentiate between osteoarthritis and rheumatoid arthritis.
Unlike rheumatoid arthritis, osteoarthritis doesn’t affect other organs.
Rheumatoid caused by immune system attacking joint linings
Osteoarthritis caused by aging (wear and tear), injury, or obesity; just limited to joints
What is the main blood supply to the knee joint?
Popliteal artery
Which arteries are involved in anastomosis around the knee joint?
Popliteal artery genicular branches
Descending geniculate artery of femoral artery
Recurrent branch of posterior artery
2 recurrent branches (anterior and posterior) of anterior tibial artery
Describe the innervation of the knee joint.
Obturator nerve posterior division
Genicular branch of tibial nerve
Genicular branch of common peroneal nerve
Femoral nerve infrapatellar branch
What happens during locking of the knee joint?
- knee is in full extention
- femur medially rotates and all ligaments become taut
- knee becomes rigid
What are the 3 landmarks located when performing a knee arthroscopy?
- Tibial tuberosity
- Lateral epicondyle of femur
- Apex of patella
What structures of the knee joint are supplied by the middle genicular artery?
cruciate ligaments
What is the function of the oblique popliteal ligament?
- Stabilize posterior aspect of knee joint
2. Prevent excessive lateral rotation of tibia
Genu varum is another name for
bowleg
In genu varum, the tibia in relation to the femur is
a) abducted
b) adducted
b) adducted
What is the normal LATERAL angle of the knee?
170 - 175 degrees
How does the lateral angle change in genu valgum?
it is less than 170 degrees
What is a normal Q angle?
In women = 17 degrees
In men = 14 degrees
