Soft Tissue Injuries of Knee Flashcards
how is diagnosis made
detailed history, clinical exam and subsequent investigation
how do meniscal injuries usually occur
twisting force on a loaded knee (turning at football)
where is the pain localised to following a meniscal injury
medial (majority) or lateral joint line
what follows a meniscal injury the following day
effusion
what do patients usually complain of following a meniscal injury
pain and then usually has mechanical symptoms
what are some mechanical symptoms following a meniscal injury
- catching sensation
- locking (difficulty straightening the knee with around a 15 degree block to full extension)
- patient may feel their knee is going to give way if a loose meniscal fragment is caught in the knee when walking
what causes ‘locking’
significantly torn meniscus flipping over and becoming stuck in the joints line
what is a clinical sign associated with meniscal tear
‘locking’
what is ‘pseudo-locking’
patient describes that their knee can ‘become stuck’ with temporary difficulty in straightening the knee particularly when rising from sitting to standing and this will either spontaneously resolve or patient has a trick manoeuvre that can resolve it
what conditions can cause pseudo-locking
arthritis
how can locking and pseudo-locking be told apart
careful history and exam
is pseudo-locking a sign of meniscal injury
no
what causes ACL rupture
- higher rotational force
- turning upper body laterally on a planted foot (internal rotation force on tibia)
- rugby, skiing, high impact sport
what might be felt or heard following ACL rupture
a pop
what can patients develop after an ACL rupture
haemarthrosis (effusion due to bleeding in the joint from the vascular supply within the ACL)
how long does it tend to develop a haemarthrosis
usually within an hour
what can patients complain of chronically
rotatory instability with their knee giving way when turning on a planted foot (due to excessive internal rotation of tibia)
what can valgus stress injuries (e.g rugby tackle to the side) tear
MCL and high forces will also potentially damage the ACL and risk lateral tibial plateau fracture
what causes a ruptured PCL
a direct blow to the tibia with the knee flexed (e.g a motorcycle crash) or hyperextension
what causes a LCL rupture
varus stress injury with or without PCL damage
why is it good to wait 2-7 days to examine the knee after any of these injuries
pain and apprehension can limit examination findings
when is an MRI used
if the injury is thought to be significant, has a suspicious history or there are multiple ligaments involved it can help delineate the extent of the injury
