and CORRECT Answers
Knee is a mechanism of 3 bones and 3 joints. What are they? - CORRECT ANSWER -
Bones: Femur, Tibia, and Fibula
Joints: Medial tibiofemoral, lateral tibiofemoral, patellofemoral
What are the functions of the joints in the knee? - CORRECT ANSWER - -to allow certain
movements
-to restrict others
-to provide load transfer though your limbs
What are the 3 axes in the knee joint? - CORRECT ANSWER - Anatomical, Mechanical,
and functional
Anatomical axis - CORRECT ANSWER - axes of the bones. Down the center of the
medullary cavity
Mechanical axis - CORRECT ANSWER - axes of alignment. on the Tibia, the mechanical
and anatomical axes are the same line.
functional axis - CORRECT ANSWER - axes around which limbs rotate.
-flexion-extension axis
What is roll-back movement? - CORRECT ANSWER - occurs during bent-knee at contact
point.
-allows for increased knee flexion by avoiding impingement
What are the primary stabilizers in the normal knee? - CORRECT ANSWER - ACL and
PCL (for anterior/posterior motion)
, MCL and LCL (for varus/valgus motion)
What is tibiofemoral joint force? - CORRECT ANSWER - position force acting on joint
What are the 3 functions of the patella? - CORRECT ANSWER - -acts a slippery surface
for the tendon as it passes over the front of the knee
-increases mechanical advantage of the quad muscles
-keeps the tendon from slipping off the side of the femur
What is the patella function and motion dictated by? - CORRECT ANSWER - -proximal
muscle action
-patella shape and congruence with the femur
-strong tendinous attachment to the tibia
What is the primary function of the patella? - CORRECT ANSWER - to increase the lever
arm of the extensor mechanism
What drives motion in the knees? - CORRECT ANSWER - shapes. shapes compliment
axes.
What are the 3 arcs of motion? - CORRECT ANSWER - Screw home (-5- 10 degrees).
functional (10-120 degrees). Deep flexion (120-150/160 degrees)
What degree does the knee have in full extension? - CORRECT ANSWER - -5 degree
Screw home arc - CORRECT ANSWER - knee EXTends the tibia with EXTernally rotate
. Passive motion
Functional arc - CORRECT ANSWER - active motion. Has two fixed axes: flexion-
extension axis and longitudinal axis.