Knee problems Flashcards
Go over the anatomy of the knee
ok lol
what mechanism leads to ACL rupture?
rotation of knee w planted foot
What are the signs of ruptured ACL
- effusion - rapid onset
- haemarthrosis
- +ve ‘anterior draw sign’
- pop felt or heard
What is the management of ruptured ACL?
rest
physio
ligament reconstruction
What is the mechanism of ruptured PCL and why is it less common than ACL
Hyperextension, less common as PCL is twice as strong as ACL
When do ruptured PCLs tend to occur?
car crashes as knee strikes dashboard
What can be found on examination to confirm PCL rupture?
positive posterior draw
increased posterior tibial displaced
What is the mechanism leading to ruptured MCL
blow to lateral aspect of knee whilst foot is fixed
forced into valgus
What are the signs of a ruptured MCL
effusion and tenderness
What is the treatment of ruptured MCL
Rest and firm support, can be managed non-operatively in most patients
What mechanism leads to a medial meniscal tear?
twist to flexed knee
What mechanism leads to a lateral meniscal tear?
adduction and internal rotation
What are the signs of a meniscal tear
limited extension delayed knee swelling joint locking recurrent episodes of pain and effusions tender joint line
what direction does the patella usually dislocate
laterally
What are the possible mechanisms leading to a patella dislocation
- direct trauma
- severe contraction of quads w knee stretched in valgus and external rotation of tibia on femur
What is the recurrence rate of patella dislocation
20%
What is the management of patella dislocation
- reduction - firm medial
- pressure whilst extending knee
- XR - check for patella fracture
immobilisation in cast/splint - rehabilitation w quad strengthening
What are the possible mechanisms leading to a patella fracture
- fall onto flexed knee
2. dashboard injury
When do patella fractures require operative fixation
if displaced
What causes patella tendinopathy
macro/micro patella tendon tears
What is the Rx of patella tendinopathy
rest and NSAIDs
Steroid injections if no rest
What is prepatellar bursitis also known as and why?
housemaids knee as it can be due to excessive kneeling
What is the presentation of pre patellar bursitis?
hx of kneeling
pain and swelling
what is the treatment of pre patellar bursitis
compressive wrap
NSAIDs +/- aspiration and immobilisation for 1 week
What is Osgood Schlatters disease?
pain +/- swelling over tibial tuberosity
What causes Osgood Schlatters disease?
traction apophysitis - inflammation and stress injury
associated w physical overuse
what is seen on XR w osgood schlatters disease?
tibial tuberosity enlargement +/- fragmentation
What is the treatment of osgood schlatters disease?
limit activity ice oral anti-inflammatories knee padding physio
What is chondromalacia patellae
softening of articular cartilage of patella
How does chondromalacia patellae present?
anterior knee pain on walking up and downstairs and rising from prolonged sitting
What is the typical presentation of a patient with OA of the knee?
> 50 years, often overweight
Pain may be severe
Intermittent swelling, crepitus and limitation of movement may occur
What are the 2 types of patella fracture?
i. Direct blow to patella causing undisplaced fragments
ii. Avulsion fracture
What is a tibial plateau fracture?
break of proximal tibia involving knee joint
Why are tibial plateau fractures significant?
tibial plateau one of the most critical load bearing areas of body
In who do tibial plateau fractures most commonly occur ?
elderly
significant trauma in young
What is the mechanism of tibial plateau fractures?
knee force into valgus or virus
knee fractures before ligaments rupture
How are tibial plateau fractures classified?
Schatzker system
Which parts of the knee does a virus and valgus injury affect in a tibial plateau fracture
varus - medial plateau
valgus - lateral plateau depressed fracture
What is important to rule out in knee dislocation (tibial displacement)
vascular injury
ABPI
Why does presence of a pulse in knee dislocation not necessarily mean there is no vascular injury?
geniculate arteries may provide collateral flow and palpable pulses masking a limb-threatening vascular injury
What artery is most commonly injured in knee dislocation ?
popliteal
