Flashcards in Knee & Leg Deck (14):
What are the important questions in the knee history?
- what does it stop you from doing?
- what analgesia have you had?
- location: inside or outside, referred from groin
- timing: rest (biological pain), activity (mechanical pain)
- progression: acute (traumatic), gradual (degenerative)
- night pain
- flexion e.g. low chair, toilet, squatting
Instability = actual or threatened, with what activities
Swelling = subjective, small effusions easily detectable
Locking = physical block to flexion/extension caused by loose body jamming the articular surfaces
Red flags =
- severe night pain
- inability to bear weight on limb
- Hx of malignancy
- rapid deterioration of knee symptoms
What are the important features of a knee exam?
- wasting (esp. quads)
- alignment: foot everted so you see more toes on that side than the other
- gait: varus thrust, stiff knee gait, bow-legged, knock-kneed
- scars: minor trauma, knee replacement, arthroscopy
- walking aids
- foot orientation and perfusion
FEEL (flexion and extension)
- swelling: sweep test, patellar test
- bony landmarks
- joints: femur, tibia, patella, fibula
- patellar grind
What are the special tests of the knee exam?
Striaght leg raise = extensor mechanism tested (quads, patellar ligament and tendon ---> tibial tuberosity)
Stability of medial and lateral collateral ligaments = flex knee to 90 degrees and push knee medially and laterally
Mobile or fixed varus/valgus deformities = try to correct
Anterior/posterior drawer test = flex knee to 90 degrees (check hamstrings are flexed) and put thumbs on front whilst fixing foot and rocking knee back and forth
Lachman's test = more senstive than anterior drawer test; knee flexed to 30 degrees, encircle femur with one hand and tibia with the other
Pivot shift test = put thumb behind fibula and use other hand to flex and pivot knee into valgus, tests for ACL tear (tibia moves with when flexed with varus movement)
McMurray's test = tests for meniscal tears, place hand between femur and tibia on both sides whilst flexing and extending knee (meniscus pinched ---> pain)
What are the investigations in the acute, traumatic knee?
Swelling, instability, joint line tenderness
X-ray to rule out fracture/dislocation
Splint and re-examine at 3wks
What are the key features of anterior knee pain?
Occurs when going downstairs
Patellar tracking (patella shifts out of place)
What are the key features of a meniscal tear?
Joint line tenderness
Arthroscopy to repair/excise meniscus
What are the key features of an ACL tear?
Body thrown over planted foot
Positive Lachmann test/anterior draw test/pivot shift test
What is osteochondritis dissecans?
Separation of articular cartilage and subchondral bone fragment from joint surface ---> fragment becomes avascular and exists as loose body within joint
e.g. genetic, ischaemia, repetitive trauma
What are the key features of septic arthritis?
Aspirate for culture and washout
What is a Segond fracture?
Avulsion fracture of knee involving lat. aspect of tibial plateau (freq. associated with ACL tear)
What is the management of a tibial plateau fracture?
ORIF OR external fixation
What is a high tibial osteotomy?
Correct valgus/varus deformity by sawing through tibia and hinging it with plate and screws/inserting a bone graft to correct the angle of weight distribution to the knee
What is Hoffa's fat pad?
Infra-patellar fat pad
Can become impinged between patella and femur, causing significant effusion