Examination of the Knee

Question 1

How many DOF are at the knee joint?

Answer 1

six

Question 2

What type of joint is the knee?

Answer 2

modified hinge joint

Question 3

What types of joint forces are experienced at the knee?

Answer 3

compression
distraction
shear
torsion

Question 4

What’s the screw home mechanism?

Answer 4

tibia ER at end range extension. bc of shape of medial condyle, tension in the ACL and pull of the quads
(tibial glide much greater on the medial side)

Question 5

what’s the normal ROM at the tbfib joint?

Answer 5

135-140 degrees flexion
0 degrees extension
(5-10 degrees = hyperextension)

Question 6

closed packed position?

Answer 6

full extension with ER

Question 7

loose packed position?

Answer 7

25 degrees of flexion

Question 8

Capsular pattern?

Answer 8

flexion loss >extension loss

Question 9

What are some problems that may be seen at the patellar grove?

Answer 9

patella alta
patella dysplasia
shallow groove (powers)
medial patella fem lig damaged
lateral retinaculum damaged

Question 10

how would the lack of a patella affect the knee?

Answer 10

25% more quad force needed to extend knee –> increase compression forces –. increased degenerative articular cartilage

Question 11

What are major guiding forces of the patella?

Answer 11

Lateral directed forces:
IT band
“bowsringing forces on patella”
lateral patella retinacular fibers

Medial directed forces:
vastus medialis (oblique fibers)
medial patellar retinacular fibers

Question 12

Normal quadriceps angle?

Answer 12

8-14 degrees in males

15-17 degrees in females

Question 13

intrinsit movement abnormalities

Answer 13

capsular tightness–> lack of extension–> rotary dysfunction (accelerated wear of joint surfaces, abnormal strain on the static/dynamic restraints)