Basic Exam of the Knee

Question 1

What are the main steps in a knee exam?

Answer 1

Prepare patient
Hand hygiene
General inspection and observation of gait
Inspection with patient lying supine
Anterior palpation of knee joint
Lateral and posterior palpation of knee joint
Testing movements of knee
Examine anterior and posterior cruciate ligaments
Examine collateral ligaments
Complete exam

Question 2

How do you prepare the patient?

Answer 2

Explain reason for exam
In general what it involves
Indicate both knees will be examined
Both knees adequately exposed
- Shoes and socks off for deformities at ankle

Question 3

What should you be looking for in a general inspection?

Answer 3

Alignment of knees in standing position

Question 4

What abnormalities in the alignment of the knees in a standing position may be observable?

Answer 4

Bowing = genu varum
Knock-knees = genu valgus

Question 5

What abnormalities may be apparent when observing a patient’s gait?

Answer 5

Limp due to
- Pain
- Deformity
Muscle wasting

Question 6

Why might knee problems cause muscle wasting?

Answer 6

Limited use of surrounding muscle groups > reduced muscle bulk

Question 7

Which muscle especially has a reduced muscle bulk because of knee problems?

Answer 7

Vastus medialis

Question 8

Which part of the knee should special attention be paid to when observing gait?

Answer 8

Back of knee

Question 9

What are you looking for when you are inspecting the knees whilst the patient is lying supine?

Answer 9

Scars
Rashes
Evidence of inflammation
- Redness
- Swelling
Ask about pain

Question 10

What are the steps for the anterior palpation of the knee?

Answer 10

Check temperature
Check for joint effusion by performing patellar tap
Check for joint effusion by performing bulge test
Palpate

Question 11

How do you check the temperature of the knee?

Answer 11

Place back of hand on skin over patella

Should be slightly cooler than surrounding areas

Question 12

What is joint effusion?

Answer 12

Fluid in joint

Question 13

How does the knee appear if there is a large amount of fluid in the knee?

Answer 13

Swollen medial, lateral, and superior to patella

Question 14

What is the patellar tap used to detect?

Answer 14

Lesser amount of fluid than visible

Question 15

How do you perform the patellar tap?

Answer 15

Warn patient that test may be uncomfortable
Place hand above patella
Milk any fluid in suprapatellar bursa into subpatellar space
- Slide hand firmly down so it rests above patella
Maintain pressure at this position
With index and middle fingers of other hand, push patella down
If effusion present
- Patella will knock against femoral condyles > tapping sensation
- Patella feels as if bouncing in joint space

Question 16

What is the bulge test used to detect?

Answer 16

Smaller effusions than those detected in patellar tap

Question 17

How do you perform the bulge test?

Answer 17

Displace fluid from medial aspect of knee into superior and lateral aspects
- Stroke upwards on medial side of patella
Apply pressure on lateral side of patella
- Stroke downwards
Observe if any fluid pushed back/bulges into medial aspect

Question 18

How do you palpate the anterior knee?

Answer 18

Systematically palpate around
- Patella
- Quadriceps insertion
- Patellar tendon
Examine for evidence of
- Heat
- Tenderness > periodically check patient's face
- Swelling

Question 19

With which knee should you start any of the tests?

Answer 19

Unaffected knee as baseline

Question 20

How do you laterally and posteriorly palpate the knee joint?

Answer 20

Ask patient to flex their knees
Palpate along medial and lateral joint lines to detect tenderness and swelling
Ask patient to straighten their knees again
Palpate posterior aspect for tenderness and swelling

Question 21

What is a common cause of swelling behind the knee?

Answer 21

Baker’s cyst

Question 22

How do you check the range of movement of the knees?

Answer 22

Compare one side with other
Observe degree of extension when patient resting legs on examination couch
Test flexion
- Bend unaffected knee by sliding foot towards bottom = active flexion
- Gently push flexed knee = passive flexion
- Ask patient if this maneuver too uncomfortable
- Observe face whilst doing this
Test other side

Question 23

What is the normal range of movement at the knee?

Answer 23

0 degrees = extension to 135 degrees = flexion

Question 24

What is flexion usually limited by?

Answer 24

Opposition of calf against hamstrings

Question 25

What does passive flexion test?

Answer 25

Extra amount knee can be flexed

Question 26

How do you examine the anterior and posterior cruciate ligaments?

Answer 26

Patient flexes knee to 90 degrees
Sit on couch and stabilise patient's leg by wedging foot under bottom
Place hands behind patient's knee
- Thumbs over tibial tuberosity
Pull forward = anterior draw test
Push backwards = posterior draw test

Question 27

What indicates an anterior cruciate ligament injury in the anterior draw test?

Answer 27

Excessive movement of tibia against femur

Question 28

What indicates a posterior cruciate ligament injury in the posterior draw test?

Answer 28

Excessive movement of tibia against femur

Question 29

How do you examine the collateral ligaments?

Answer 29

Start with unaffected knee to establish normal degree of laxity
Support patient’s lower leg between your arm and body with knee slightly flexed
Test medial collateral ligament - apply valgus stress to knee
- Place one hand on lateral aspect of knee
- Use other hand to support ankle/calf
- Push inwards at knee with one hand
- Provide opposing force with other hand at ankle
Test lateral collateral ligament - apply varus stress to knee
- Place one hand on medial aspect of knee
- Use other hand to support ankle/calf
- Push outwards at knee with one hand
- Provide opposing force with other hand at ankle

Question 30

What does laxity of the collateral ligaments indicate?

Answer 30

Damage