Manual 102-105: Arthrology and Syndesmology of Leg Flashcards
how many joints in knee joint?
- compound joint consisting of two joints between the condyles of tibia and femur and a joint between the patella and femur
- joint is enclosed by one synovial membrane and contains only one cavity
movements occurring at knee joint
- hinge, gliding, and some rotation
what type of joint is the knee joint
condyloid joint
- articulations between condyles of tibia and femur form condylar joints
- patella articulating with lower anterior part of the femur forms a saddle or sellar type joint
the tibia and femur meet at about ________ degrees from the midline
10-20 degrees
- an exaggeration of this angle leads to a condition known as genu valgum
does the articular capsule completely surround the knee joint
no
- it is incomplete anteriorly where it is replaced by the medial and lateral retinaculi of the quadriceps tendon
- capsule is attached to margins of articulating surfaces
- on lateral side , tendon of popliteus passes through
continuation of the quadriceps tendon below the patella
patellar ligament
- attaches to the tibia at the tibial tuberosity
strong, flat band on the anterior, inferior part of the knee joint about 8 cm long
patellar ligament
what separates the patellar ligament from the synovial membrane? from the tibia?
- infrapatellar fat pad
- infrapatellar bursa
strong, round fibrous cord extending from the lateral epicondyle of femur, above the groove for the popliteus m. to the head of the fibula (lateral side)
fibular collateral ligament
is the fibular collateral ligament attached to the capsule or lateral meniscus?
no
- it is separated from the lateral meniscus by the articular capsule and the tendon of the popliteus m.
where does the tendon of biceps femoris attach in relation to the fibular collateral ligament?
- the fibular collateral ligament is covered by the tendon of the biceps femoris m. that splits to attach to the head of the fibula on either side of the fibular collateral ligament
the tendon of the popliteus m. is _____ to the fibular collateral ligament
deep
when was the anterolateral ligament located?
- french surgeon, paul ferdinand segond, first describe this ligament in 1879
- detailed anatomical description was not available until 2013
describe the anterolateral ligament
- proximally attached to lateral femoral condyle just anterior to the proximal attachment o fibular collateral ligament with connecting fibers between the two ligament commonly observed
- fibers take an oblique course to its more anterior distal attachment on the anterolateral aspect of tibia between gerdy’s tubercle and the apex of fibula
- also secure attachment to lateral meniscus
what is the functional purpose of the anterolateral ligament
check internal rotation between 30 and 90 degrees of knee flexion
attachments of medial collateral ligaments
- from the medial epicondyle of the femur to the medial surface of the tibia
- attaches to femur below adductor tubercle
- attachment along shaft of tibia for 2-3 cm
- firmly attached to medial meniscus
how long is the medial collateral ligament?
broad flat band about 10 cm long
at the inferior end of the medial collateral ligament, what tendons cross it?
- tendons of gracilis, sartorius and the semitendinosus muscles cross it
most of the fibers of this ligament come from an expansion of the tendon of the semimembranosus ligament
oblique popliteal ligament
describe oblique popliteal ligament
- fibers pass obliquely from the medial condyle of the tibia to the lateral condyle of the femur
what blood vessels perforate the oblique popliteal ligament?
- medial genicular on the way to the knee joint
- popliteal vessels rest on its external surface
describe the arcuate popliteal ligament
- formed by the thickening of capsular fibers that arch over the tendon of the popliteus m.
- fibers travel medially from the lateral condyle of the tibia ad the head of the fibula to attach to the posterior intercondylar area of tibia
joined to the tibia at the anterior intercondylar area, travel superolaterally to attach to the posterior part of the medial surface of the lateral femoral condyle
anterior cruciate ligament
action of anterior cruciate ligament
prevents hyperextension of the knee by preventing posterior sliding of the femur on the tibia
stronger and shorter cruciate ligament
posterior
attachments of posterior cruciate ligament
- arises from posterior intercondylar area of the tibia and travels obliquely upward, crossing the anterior ligament to attach to the lateral surface of the medial condyle
action of the posterior cruciate ligament
- prevents hyperflexion of the knee by preventing forward sliding of the femur on the tibial plateau
separate the joint cavity between the condyles of the tibia and femur
menisci
purpose of the menisci
semilunar fibrocartilagnious discs that deepen the cavity of the tibial condyles
which part of the menisci is thickest?
outer border of each meniscus is thicker than the central area, which is in contact with femoral condyles
each meniscus covers about ________ of the corresponding condyle of the tibia
2/3
peripheral attachment of each meniscus to the fibrous capsule
coronary ligament
- this structure holds the menisci to the tibial condyles
unites the two menisci anteriorly
transverse ligament
attachments of medial meniscus
- attached to tibia anterior to the anterior cruciate ligament at the intercondylar area
- posterior attachment is at the posterior intercondylar area
- semicircular shape
attachments of lateral meniscus
- extends from anterior intercondylar area to the posterior intercondylar area
- some fibers extend to medial condyle of the femur
how often are there anterior and posterior meniscofemoral ligaments?
- 70% of the time
- extend to the medial condyle of the femur from the posterior side of lateral meniscus
shape of lateral meniscus
circular
what separates the lateral collateral ligament from the lateral meniscus?
tendon of popliteus muscle
n. supply to knee joint
- articular branches of femoral, obturator, common peroneal and tibial nerves
blood supply to knee joint
- genicular anastomosis produced by descending genicular branch of femoral, the genicular branches of popliteal, recurrent branches of anterior tibial, descending branch from the lateral femoral circumflex arteries and circumflex fibular a.
what forms the proximal tibiofibular joint
- fibular facet on the posterolateral aspect of the lateral tibial condyle and the articular facet on the medial aspect of the head of the fibula
- both circular facets
in approximately _______% of the population, the joint cavity of the superior tibiofibular joint is continuous with that of the knee joint
10%
what type of joint is the distal tibiofibular joint?
syndesmosis, fibrous type
articualtions of distal tibiofibular joint
triangular surface of distal fibula, which lies at the inferior aspect of its interosseous border, articulates with distal end of tibia
three ligaments associated with distal tibiofibular joint
- interosseous tibiofibular ligament (distal continuation of interosseous membrane)
- anterior inferior and posterior inferior tibiofibular ligaments (directed inferolaterally)
shape of anterior inferior tibiofibular ligament
triangular
shape of posterior inferior tibiofibular ligament
quadrangular
inferior transverse ligament
- deep part of posterior inferior tibiofibular ligament
- helps form socket for the talus
- courses from the lateral malleolar fossa to the margin of the medial malleolus