Musculoskeletal (Knee)

Question 1

What are you looking for on inspection of a standing patient?

Answer 1

Inspect from front, side and back for: 
Valgus deformity (knock-knees)
Varus deformity (bow-legs)
Genu recurvatum (knee hyperextension)
Flexion deformity 
Swellings in the popliteal fossa ie Baker's cyst (RA/OA)
Comment on stance

Question 2

What are you looking or on inspection of a supine patient (with hips and knees extended)?

Answer 2

Symmetry 
Valgus + varus deformities 
Skin changes ie psoriasis 
Scars 
Swelling - especially in the medial fossa 
Muscle wasting - especially the medial quadriceps (vastus medialis)
Displacement of the patella 
Fixed flexion deformity

Question 3

What are you looking for on palpation?

Answer 3

Assess and compare temperature over bones and joints
Palpate around the borders of the patella for tenderness
Palpate the popliteal fossa for swelling or cysts
Assess for an effusion by performing the bulge test (sweep hand firmly up medial fossa over suprapatella pouch and down the lateral fossa - medial fossa may refill producing a bulge of fluid if an effusion is present ) or patellar tap
Flex the knee to 90 degrees, palpate the joint line and tibial tuberosity where patellar inserts for tenderness

Question 4

How do you assess the ROM?

Answer 4

Ask the patient to actively flex and extend their knee
Assess passive movement of knee by placing a hand on it and flexing it as far as possible with the other
Palpate for crepitus during passive flex/ext

Question 5

What is the posterior sag test?

Answer 5

Position patient with knee flexed at 90 and foot flat on bed, inspect from side - posterior sag of the upper tibia with a ‘step’ visible below the patellar suggests post. cruciate ligament damage

Question 6

What is the anterior draw test?

Answer 6

Position patient with knee flexed at 90 and foot flat on bed, place fingers into popliteal fossa and thumbs on tibial tuberosity and pull forward - significant movement=positive draw test and suggests ACL damage
If you also do a push in this position, can test for PCL damage (like the sag test)

Question 7

What is the lateral collateral ligament test? and medial collateral ligament test?

Answer 7

Flex the knee at 20 degrees, hold the patients heel with one hand and apply pressure to the inside of the knee with the other - an asymmetrical lateral gaping indicates LCL damage.
- as above but apply pressure on the lateral aspect of the knee and assess for medial gaping

Question 8

What is the Lachman’s test?

Answer 8

Can be used instead of anterior draw
Flex the knee at 20 degrees, place one hand behind tibia with thumb on tibial tuberosity, grasp patients thigh with other hand and pull anteriorly on the tibia
You should feel a firm end-point as the ACL prevents forward translocation of the tibia on the femur
A soft end-point suggests ACL damage

Question 9

What is McMurray’s test?

Answer 9

Designed to trap/catch a torn meniscus between femoral condyle and tibial plateau and should only be performed if history is suggestive of torn meniscus
Flex patients hip to 90 and maximally flex the knee, externally rotate the knee and move the knee from the fully flexed position to fully extended
Repeat the test with internally rotating the knee
A palpable/audible/painful click over the medial or lateral joint indicates a meniscal tear
Test is useful when positive, unreliable when negative and is difficult to perform on a painful knee