This is a magical time of year for the British paediatric emergency
physician as children and young people are getting far fewer illnesses. Instead of wall to wall snot and vomit, the
paediatric waiting area is filled with injuries of all varieties. Although I assume that obvious fractures will
present directly to the Emergency Department, many injured children will also
present to primary care. This tip
applies equally to both settings. Hidden
amongst all of the injured children will be a ‘something else’ from time to
time. They are particularly hard to spot
but there are a few things that can help.
In most cases there is no doubt that an injury actually is
the case of the pain. If the mechanism
fits, go with it. (Well doc, he cycled
off the roof. Do you think that’s why
his leg hurts?) What we are talking about here are soft presentations. These are
the things that present as injury but are in fact the manifestation of
something else:
- A hip thing (Transient synovitis, Perthe’s or Slipped Upper Femoral Epiphysis)
- Juvenile Idiopathic Arthritis (JIA)
- Infection (septic arthritis and osteomyelitis)
- Apophysitis (the most common being Osgood-Schlatter’s)
- Malignancy (e.g. Osteosarcoma)
Even excluding the odd one out in that list (transient
synovitis, or irritable hip to give it its other name), these conditions
comprise a surprisingly large number of injury presentations. So in order to avoid the pitfall of allowing
the presentation to frame your diagnosis, ask the following questions:
Is it the hip?
This is a deceptive question but an important one as hip
problems are rarely true injuries. Very
often the child either has referred pain to the knee or, if younger, does not
localise the pain at all, choosing to blame their foot or another random body
part. So for any lower limb problem
without a blatant cause the hip must be assessed. If the hip is then found to be suspect, what
you do next depends on your experience and where you work. I would suggest that any of these factors mandates
urgent referral of a suspected hip problem:
- Age over six
- Fever
- Unable to weight bear on that limb
How long has the pain really been there?
In any of the chronic causes of pain the symptoms may have
been present for a considerable time.
Despite this the pain is often put in the context of a football game or
other event. In many cases there was no
injury as such, simply a worsening of pain after a fall or an exertion. Any pain that was there already and was made
worse by anything should be assumed to have a chronic cause. This may be something relatively benign such
as Osgood Schlatter’s disease but it may also be something more in need of
early detection such as Juvenile Idiopathic Arthritis or a malignancy such as osteosarcoma or leukaemia.
Is the child unwell and is the ‘injury’ hot to touch?
Septic arthritis and osteomyelitis are thankfully both rare
in children. They are also completely
devastating and rather difficult to detect.
If infection is suspected, refer and do not allow the buck to be passed
back in the form of advice to do some blood tests to rule out infection. If the onset is acute or the child is very
young, inflammatory markers may not yet be raised. (1) Juvenile idiopathic arthritis can also cause
hot, swollen joints and may even cause systemic symptoms.
Is the problem bilateral?
If there are two of the same body part affected (and no good
mechanism to explain this) the possibilities are limited. Thankfully you can essentially rule out
infection and tumour. What becomes much
more likely is one of the other possibilities.
Although an apophysitis is more probable if the tibial tuberosity or the
Achilles tendon insertion is involved, other bilateral pains make juvenile
idiopathic arthritis much more likely.
Have there been other mysterious joint aches over the past
months or years?
One of the laments of the paediatric rheumatologists is that
children present late with juvenile idiopathic arthritis (JIA). Recurrent pains in children are often put
down to growing pains. While it is true
that young people often get unexplained pains that are not related to any of
the above conditions, it is also important to look for the signs and symptoms
of JIA. One of the most important
considerations is the recurrent nature of the pain. Severity is often difficult to assess as
children and young people are surprisingly likely to under-report chronic
pain. They tend to assume that it is
nothing (after all they haven’t yet learned to worry about all the serious
possibilities that occur to their adult counterparts) or simply alter their
activity so that the pain has little impact.
If JIA is suspected, examine the affected joint(s) for
swelling and perform a PGALS screen which will detect other joints that are
affected which may not have been volunteered in the history.
In summary, most children that present with minor injuries
do indeed have minor injuries, with the exception of hip pain, which is usually
something unrelated to an injury. Hip
pain aside, it is easy to miss the rare causes of bone and joint pain. Asking about the mechanism of ‘injury’ and
pre-existing or recurrent symptoms may help to uncover chronic causes. Examination of the affected part and
consideration of the possibility of infection are also important if there is
any possibility that the history of injury is a distraction. Any unremitting well localised pain should
raise the possibility of malignancy(2) unless another good explanation can be
found. Finally juvenile idiopathic
arthritis is uncommon but needs to be actively sought as it is easy to miss.
Edward Snelson
@sailordoctor
Disclaimer: I’m
talking rubbish: I’ve just had a peek in
the waiting room and it is wall to wall snot and vomit after all…
(1) BRITISH
SOCIETY FOR CHILDREN'S ORTHOPAEDIC SURGERY The management of acute bone and
joint infection in childhood - A guide to good practice
(2) Suspected cancer (part 1—children and young adults): visual overview of updated NICE guidance BMJ 2015; 350 doi: http://dx.doi.org/10.1136/bmj.h3036
http://www.bmj.com/content/350/bmj.h3036
http://www.bmj.com/content/350/bmj.h3036