Knee & Leg Flashcards
What are the important questions in the knee history?
Pain =
- 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
Stiffness =
- start-up
- flexion e.g. low chair, toilet, squatting
- occupation
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?
LOOK
- 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
- varicosities
- walking aids
- foot orientation and perfusion
FEEL (flexion and extension)
- swelling: sweep test, patellar test
- bony landmarks
- joints: femur, tibia, patella, fibula
- osteophytes
- pulses
- patellar grind
MOVE
SPECIAL TESTS
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
MRI
Splint and re-examine at 3wks
What are the key features of anterior knee pain?
Occurs when going downstairs
Gives way
Crepitus
Swelling
Pseudo-locking
Patellar tracking (patella shifts out of place)
What are the key features of a meniscal tear?
Twisting/hyperflexion injury
Locking
Swelling
Joint line tenderness
Arthroscopy to repair/excise meniscus
What are the key features of an ACL tear?
Body thrown over planted foot
Acute swelling
Giving way
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?
Unwell
Pain
Tense effusion
Very stiff
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
What is Osgood-Schlatter disease?
Inflammation of patellar ligament at tibial tuberosity characterised by painful lump just below knee (tibial tubercle)
Caused by osteochondritis or traction apophysitis of tibial tubercle
