Professor Wilson explains the difficulties of examining the knee when it is acutely painful and swollen.
First published by knee surgeon Adrian Wilson in 2010, and reviewed August 2023 by Dr Sheila Strover (Clinical Editor)
Assessing the severely swollen knee after an injury - the context
Examining any knee needs to be tailored to the individual and the particular clinical scenario or problem -
- For example, if a child walks into the consulting room one immediately starts to think about the paediatric knee and its association with, for instance, the hip and the spine, and the examination needs to be tailored very much in a specific way towards paediatric problems.
- If someone sporty comes in, one immediately thinks of ligament instability, meniscal problems, chondral damage.
- In an individual with a large swollen painful knee that has just flared up without any injury, one immediately thinks “Is this an infection or an inflammatory condition such as gout or the first presentation of an inflammatory arthropathy such as rheumatoid arthritis?”
- In the elderly patient walking in with bandy legs, who is stiff and in significant pain, you tailor your examination towards the arthritic patient.
Missed MCL injury - a common problem
A relatively common occurrence is to fall over and suffer a combination of injuries, and traditionally we have spoken about the ‘terrible triad’ of ACL, medial collateral ligament (MCL) and meniscal pathology. If you go to A&E with this diagnosis and the MCL injury is significant and missed, and you are not braced appropriately, then it’s much more likely that you are going to need to have surgical intervention for the medial collateral ligament injury. If, however, the medial collateral ligament injury was picked up, and that is relatively easy to do with clinical examination, then the knee needs to be braced in a slightly bent position, in which case 9 times out of 10 the ligament will heal uneventfully. Often patients have these injuries totally missed, and the patient can turn up as late as 18 months after the injury with chronic instability and then that is a major challenge for any knee surgeon.
At my hospital we regularly educate the nurses and doctors in A&E to encourage them to send the acutely swollen knees to our knee clinic where the patient can be seen by a knee specialist and the injuries as listed above – and which we will later talk about again – are picked up early and treated appropriately. Maybe we surgeons see a skewed population as we see the ones that don’t settle, but so many young people are coming into the clinic now aged 30+ finding that they have got chronic instability having had an injury five years before, and now they have wrecked their knee and are really beginning to run out of options.