Lecture 8 Flashcards
What is the largest joint in the body?
The Knee
- in some ways is also the most complicated joint in the body
- is quite frequently injured
What two articulations compose the Knee Joint?
- articulation b/w Femur & Tibia
+ - articulation b/w Femur & Patella(Knee Cap) - Patellofemoral joint
- the knee joint has a joint space with the femur
What is the Patellofemoral Joint?
articulation between the Patella and Femor
- one component of the Knee Joint
2. articulation between Femur & Tibia
What 2x things does the articular cavity of the knee include?
- Patellofemoral Joint
2. Tibiofemoral Joint
What are the 2x key mechanisms surrounding the Knee Joint and Movement?
- Big Hinge joint - that allows mainly flexion and extension
- Locking Mechanism : when knee is fully extended, there is a decrease in energy required to maintain a straight leg - i.e. when standing or walking
What is the Locking Mechanism of the Knee?
When your knee is fully extended, there is a decrease in the energy required to maintain a straight leg (i.e. when standing or walking)
What are the main movements of the knee joint?
Mainly Flexion and Extension
-as is a Big Hinge joint essentially
What sort of bone is a Patella, and what are its corresponding features?
sesamoid bone: a bone that lives Within the tendon
-there are sesamoid bones in wrist and feet
Made into sesamoid bone by Patellar Ligament (continuation of quadriceps mechanism)
Function to Protect the tendon:
patella is articulating/rubbing over the femur, and protects the tendon from Femur
- would wear through and rupture really fast
(bone-on-bone»_space; obviously alot stronger than tendon-on-bone)
Where do the quadriceps attach to the knee?
Anteriorly and Inferiorly
onto boney ridge = Tibial Tubercle
-necessary for knee Extension (if insertion was above patella wouldn’t be able to extend/carry out its function)
What mechanism is the Patella part of?
Quadriceps Mechanism
Main stabiliser of the Knee
initial part of rehab for someone with injured knee
-normally sufficient rehab to return back to a functioning knee
What is the Patella Alignment?
Line of pull of Quadriceps = pulls patella slightly Laterlal Boney anatomy (lateral condyle) stops patella from dislocating laterally -Lateral Condyle (flexed distal femur) projects Further Forward than medial condyle (Femur is different on either side distally to stop patella from dislocating laterally)
What is the boney anatomy of the distal femur like?
Lateral Condyle projects further forward, in order to stop patella from dislocating laterally (due to the pull of the quadriceps)
What does Cruciate mean?
cruciate = “cross”
2x ligaments locate DEEP inside the knee
Stability of the Knee in AP plane– Very Important
Both originate Deep from the internal aspect of Femoral Condyles
Both insert onto superior aspects of the Tibia onto the Tibial Spine/Intercondylar Region of Tibia (Anterior/Posterior Tibial spine)
Posterior C.L: stops tibia from sliding backwards - walking down stairs, allows you to stabilise knee joint, to load a flexed/partially bent knee
Anterior C.L: stops Excessive Anterior Translation/tibia sliding forwards when Walking = common activity therefore Really important
Cruciate Ligaments are WITHIN knee Joint, but OUTSIDE of articular cavity
What is the function of the Posterior C.L?
Posterior Cruciate Ligament
Posterior Tibial spine –> Medial Femoral Condyle
Stops the Tibia from sliding backwards/posteriorly (on the femur)
Walking down stairs
STABILISEs knee joint
allows you to Load off a partialy bent/flexed knee
What stabilises the knee and allows you to load off a partially bent/flexed knee?
Posterior C.L Cruciate Ligament
What is the function of the Anterior C.L?
Anterior Cruciate Ligament
Anterior tibial spine –> Laterla Femoral Condyle
Stops Excessive Anterior Translation/ tibia sliding forward onto Femur during walking
When Walking –> therefore really important
What is the main function of both Anterior and Posterior Cruciate Ligaments?
Stability of the knee in the AP plane
What is the Deep/underside surface of the Patella covered with?
Articular cartilage
-so it can move on the Femur
What is articular cartilage located on the patella?
Knee Cap
Deep/Underside surface of the Patella
so that it can move on the Femur
What is another name for the Tibial spine and what is located there?
Intercondylar region of the tibia
=tibial spine
Anterior and Posterior cruciate ligaments originate from there
What is the origin and insertion for both the anterior and posterior Cruciate Ligament?
- Anterior Cruciate Ligament
Anterior Tibial spine –> Medial Condyle - Posterior Cruciate Ligament
Posterior Tibial Spine –> Lateral Condyle
(technically Anterior intercondylar region /Posterior intercondylar region)
Within Knee Joint
Outside of Articular Cavity
What is the location of the cruciate ligaments?
Inside Knee Joint
Outside Articular Cavity
Are the cruciate ligaments inside or outside of the articular cavity?
Outside Articular cavity
Inside Knee Joint
What is the Patellar Ligament?
continuation of quadriceps mechanism
-Makes the patella a sesamoid bone
Superior attachment: Inferior margins of Patella
Inferior = Tibial Tuberosity
What are the Superior and Inferior attachments of the Patella Ligament?
Superior attachment= Inferior margins of Patella
Inferior Attachment = Tibial Tuberosity
What is the Patella ligament a continuation of and what is its relationship with the patella?
Patella ligament is a continuation of Quadriceps Mechanism
Makes Patella into a sesamoid bone
What are the 2x knee alignments?
- Varus = Bow Legged (older people)
2. Valgus = Knock kneed
What is the knee alignment called for people who are knock-kneed?
Valgus align.
What is the knee Alignment called for people who are bow-legged?
Varus Align.
What are essential features of the Collateral Ligaments?
attached to the side of the need (“co”=paried “lateral”=to the side”)
MCL = Medial Femoral epicondyle –> Medial Tibia (posterior to Pen Anserinus attachment) -Broad, blends into underlying joint capsule
LCL = Lateral femoral epicondyle –> Fibula head. Cord like. Discrete from joint capsule
Medial (tibial) Colateral Ligament MCL
Gives sideways stability to knee joint
Medial Femoral Epicondyle –> Medial Tibia
runs more Posteriorly
Injured more regularily, and occurs to all 3x components which fuse
Posterior to Pes Anserinus attachment
Broad ligament
Blends with the Joint capsule
Lateral (fibular) Co-Lateral Ligament LCL
Gives sideways stability to knee joint Lateral Femoral Epicondyle --> Fibular head Cord like ligament Discrete from joint capsule Relatively strong
Which co-lateral ligament is broad?
MCL Medial Co-lateral Ligament
Which co-lateral ligament is attached to the Medial Tibia?
MCL Medial Co-lateral Ligament
Which co-lateral ligament is cord-like?
LCL Lateral Co-lateral Ligament
Which co-lateral ligament is posterior to Pes Anserinus?
MCL Medial Co-lateral Ligament
Which co-lateral ligament is is attached to fibula?
LCL Lateral Co-lateral Ligament
Which co-lateral ligament is discrete from Joint Capsule?
LCL Lateral Co-lateral Ligament