Data and imaging interpretation - The knee joint

Question 1

What is the assessment used to identify if a Knee X-ray is required?

What are the points to this ?

Answer 1

Ottawa Knee Rules

Question 2

What is Varus ?

Answer 2

The terms varus and valgus refer to the direction that the distalsegment of the joint points.

Question 3

What is Valgus ?

Answer 3

The terms varus and valgus refer to the direction that the distalsegment of the joint points.

VaLgus – tibia points Lateral

Question 4

What type of joint is the knee ?

Answer 4

Synovial joint

Question 5

What are the three main bones to the knee ?

Answer 5

Synovial:
Femur
Patella
Tibia
(Fibula)

Question 6

When is the knee most stable ?

Answer 6

Most stable when extended – here have max area of contact

Question 7

What is the function of the patella bone ?

Answer 7

Its gliding motion across the femur allows smooth extension at the knee and increases the mechanical advantage of the quadriceps

To cope with the potential large forces from activities such as running, the patella has the thickest articular cartilage in the body.

Question 8

What shape is the posterior aspect of the lateral condylar surface ?

What does this allow ?

Answer 8

The posterior aspect of the lateral condylar surface is bevelled. As will be described later, this allows the lateral meniscus to slide backward when the knee flexes.

Question 9

What is this ?

What causes it ?

Answer 9

Patella dislocation

Cause:
The alignment of the femoral and tibial shafts is such that the quadriceps pulls the patella superiorly and laterally
Increase risk with females

Knee effusion increases the risk of patella dislocation because vastus medialis quickly wastes.

Question 10

What prevents a knee dislocation occuring ?

Answer 10

Prominent lateral part of the trochlea groove

Vastus medialis (MOST IMPORTANT)

Question 11

What muscle is very important for keeping the patella in place? You

Answer 11

Vastus medialis

Question 12

76 yo
Changing the bulb in the corridor
Felt from the ladder directly onto the right knee
Pain/ swelling/ 0 ROM/ unable to WB

What is this ?

What can be an issue with this ?

Answer 12

Femoral Supracondylar fracture

Question 13

30 yo
RTA 60 mph- significant damage to the car
Hit the knee in the dash board
Pain++
Tender over patella

What is this ?

Answer 13

Patella fracture

The quads muscles commonly pull this muscle up seperating the two.

Question 14

45 yo
Felt from the fence 3 m high
Pain and swelling to the knee
0 ROM
Not WB

Answer 14

Tibia Fracture