Patella Flashcards
Where is the patella located?
At the front of the knee joint, within the patellofemoral groove of the femur
Where does the patella attach?
Superiorly to the quadriceps tendon
Inferiorly to the patallar ligament
What is the patella classified as?
A sesamoid type bone
Why is the patella classified as a sesamoid type bone?
Due to its position within the quadriceps tendon
What shape is the patella?
Triangular
Where is the apex of the patella situated?
Inferiorly
What is the apex of the patella connected to?
The tibial tuberosity
How is the apex of the patella connected to the tibial tuberosity?
By the patella ligament
What does the base of the patella form?
The superior aspect of the bone
What does the base of the patella provide?
The attachment area for the quadriceps tendon
What does the posterior surface of the patella articulate with?
The femur
What is the posterior surface of the patella marked by?
Two facets, the medial facet and the lateral facet
What does the medial facet of the patella articulate with?
The medial condyle of the femur
What does the lateral facet of the patella articulate with?
The lateral condyle of the femur
What are the main functions of the patella?
Leg extension
Protection
How is the patella involved in leg extension?
Enhances the leverage that the quadriceps tendon can exert on the femur, increasing the efficiency of the muscle
How is the patella involved in protection?
Protects the anterior aspect of the knee joint from physical trauma
What happens in patellar dislocation?
The patella bone is displaced out of the patellofemoral groove
What % of knee injuries does patellar dislocation account for?
~3%
In what manner do most patellar dislocations occur?
Laterally
What are patellar dislocations caused by?
A high force impact on the patella or a forceful, sudden twisting of the knee
What do patellar fractures usually result from?
Direct trauma to the bone, or sudden contraction of the quadriceps muscle
Who are patellar fractures more common in?
Males in the 20-50 age range
What happens if the patella fractures into fragments?
They will usually separate- the proximal fragment displace superiorly by the quadriceps tendon, and the distal fragment pulled inferiorly by the patellar ligament
