Examination of the knee Flashcards
When a knee injury is acute, what should you be thinking of?
Mechanical injury
- ligamentous
- meniscus
- tendon
3 broad parts of the knee assessment:
standing, walking, lying
Before starting “look, feel, move” what’s the first thing you will do?
Observe their gait
- have them walk across the room & back
varus vs. valgus deformity
Varus –> bow-legged
Vagus –> knee-knocked
Look; inspection of knee:
- inspect the knee initially whilst standing for valgus or varus deformity
- inspect the posterior knee for any swelling (Baker’s cyst)
- lie pt down in supine –> legs completely uncovered and normal knee exposed too for comparison
Observe; person & position of knee:
Look for muscle wasting of quadriceps (VM), deformity, scars, swellings
Types of swelling you may observe (2)
(a) generalised swelling as with an effusion - evident by loss of patellar recesses on either side of the patella
(b) localised swelling as with osteophytes, prepatellar or infrapatellar bursitis
What to asses during palpation of knee:
- skin temperature (comparing side to side)
- fluid in joint
- point tenderness or swelling
- bone/soft tissue contours
Examination for presence of fluid within the joint with (3 options):
(a) Small effusion - Bulge or swipe sign: milking the fluid away from the medial recess and then watching it refill when pressure is applied over the lateral recess of the patella
(b) Medium effusion - Patella tap - push fluid in suprapatella bursa then fluid will accumulate over patella
(c) Testing for the presence of cross fluctuation
Major anatomical landmarks to consider for joint tenderness/swelling:
- patellar tendon
- tibial tuberosity
- tibial plateau
- patella
- femoral condylar ridges (start low and work way up)
- joint margins
- ligament and tendon insertions (MCL/LCL)
- Baker’s cyst (posteriorly)
Movements to asses:
- active and passive compared to normal knee
- active movements should be performed first as this will indicate if significant pain is present
- Active –> ask patient to bend both knees as far as possible, bringing heels to buttocks. Is there any pain on movement?
- Passive –> left hand over patella. Is there any crepitation on movement?
Limitation of movement (locking) implies…
torn meniscus or osteochondral loose body
Normal extension of knee is usually limited to
10 degrees
The ability to extend the knee to zero degrees or more suggests hypermobility / ligamentous laxity.
Tests for integrity of ligaments
Collateral ligaments: knee slightly flexed and medial and lateral movements of the lower leg on the femur looked for while steadying the thigh
ACL/PCL: knee is held flexed to 90˚ and while patient’s foot held steady, move the lower leg anterior and posterior, looking for amount of movement of the lower leg at the knee
Test if recurrent dislocation is suspected:
patellar apprehension test
Test if meniscal tear is suspected:
McMurray’s test
Two types of gait to look for:
Antalgic gait - limp; stance phase shortened from pain
Fixed flexed knee gait - from fixed flexion deformity (like from arthritis); will cause anterior knee & quad pain
Feel - Anatomical analysis
- knee bent at 90˚ & systematic palpation w/ one finger
- walk way around to posterior part of medial meniscus, into popliteal fossa
- medial &; lateral femoral condyles; start low and work way up
- fibular head, MCL/LCL (know how to locate)
Palpation of patellar-femoral jt
- medial & lateral retinacular attachment (torn with dislocation)
- patella grind test (for PF jt pain)
