Transient Synovitis of the hip (Irritable hip)

A common presentation in young children is the mysterious limp.  Transient synovitis (irritable hip) of the hip is the most common cause of an unexplained limp under the age of 6.  The current usual practice is to make the diagnosis of irritable hip on clinical grounds.  It is no longer routine practice to support this diagnosis with blood tests or imaging.  This development in practice opens the possibility for a young child with a mysterious limp to be managed outside of a hospital setting where appropriate.

What is transient synovitis of the hip (irritable hip)?
The cause of transient synovitis of the hip is unclear.  It is presumed that most cases are a reactive arthritis with a viral trigger.  Injury can also be implicated but it is unclear whether such associations are causal or simply bring the problem to someone’s attention.  It is also common to find typical features of transient synovitis of the hip in children who have no history of viral illness or injury.  There is therefore no need to rely on a history of a possible trigger to make the diagnosis.

As the name suggests, there is inflammation of the synovium of the hip.  Ultrasound may show or synovial thickening or increased fluid.  Inflammatory markers are not usually significantly raised.  Neither of these investigations is reliable and no longer done routinely since the gold standard is clinical diagnosis.

How is transient synovitis of the hip diagnosed?
Typical features of transient synovitis of the hip are:

• Unexplained onset of limp (no history of more significant injury consistent with fracture)
• Well and afebrile child with no signs or symptoms of other significant acute illness
• Unilateral hip signs – painful or reduced range of movement

If a child has these features and no signs of another cause, the diagnosis is almost certainly irritable hip.  Other important diagnoses to consider are:

• Septic arthritis - usually presents with fever and complete refusal to weight bear
• Osteomyelitis - usually febrile and there is localised tenderness or swelling in the bone
• Toddler fracture - undisplaced fracture of the tibia usually presents with complete refusal to weight bear and has localising signs in the tibia (tender or slightly warm to touch)
• Other significant fractures are usually accompanied by localised swelling or tenderness and are clinically obvious.
• Juvenile idiopathic arthritis (JIA) - This is very uncommon under the age of 6.  Obvious swelling of a single joint (without signs of infection) may indicate a transient arthritis of a joint other than the hip.  If the affected joint is the hip and the diagnosis is JIA, this will probably be clinically indistinguishable from irritable hip.  However the child would only need to be referred if the arthritis persisted for several weeks, so analgesia and watchful waiting is the initial management in any case.  If multiple joints are involved or symptoms cannot be managed easily, early referral is indicated.
• Perthe's disease - The cause of this disease of the hip is unknown.  The femoral head becomes avascular and breaks down.  The typical age is a school age child but there is some overlap with the age at which irritable hip presents.  The unexplained limp in a child over the age of six should raise suspicion of Perthes disease.  Under the age of six, progressive symptoms or symptoms that fail to improve after a few days are concerning.
• Non- musculoskeletal - Limp may be a sign of pathology unrelated to the lower limb.  Abdominal pain or scrotal pain can cause a child to limp.

One of the best discriminators between all of these problems is the course of the symptoms.  While symptoms can vary in any illness, a significant fluctuation in pain and limp is most indicative of transient synovitis of the hip.  While syptoms may be still present after three days, it is unusual not to see significant improvement in that time.

A typical presentation, absence of red flags and a classical course of the symptoms usually make it obvious when the problem is irritable hip.  If all of these things apply, management is watchful waiting with good safety netting advice.

Edward Snelson
@sailordoctor

The Evil Twin - Orthopaedic Problems in Children Pt 2: Painful Presentations

Pretty much every individual symptom in children is likely to be something which is either normal or at very least will follow a benign course. Orthopaedic presentations are no exception.  If you've already read part 1 (orthopaedic problems in children) and came away with the impression that almost all children with bow legs, knock knees, in-toeing etc are essentially normal and that the problem is likely to self-resolve, you're not wrong.

This is one of the wonderful things about paediatrics.  Many concerning presentations are actually normal, allowing us to feel like we've done something great just by reassuring a parent that their child doesn't have anything wrong with them.  Also, many problems self resolve allowing us to take a light touch approach, avoiding unnecessary tests or treatment, always remembering to act in the best interests of the child.

These factors are also one of paediatrics greatest difficulties.  Everything is normal, except when it isn't and everything in children's health has an evil twin.

Let me give you some non-orthopaedic presentations as examples.

Paediatric orthopaedics is similarly riddled with presentations where the likelihood is that it is something that needs no intervention, while there always exists the possibility of a much more problematic pathology.  Like the evil twin (often used as a complicated anti-hero in literature and film) concept, the pathology that we have to be wary of usually shares many characteristics with the more benign explanation for the symptoms.  Since common things are common, the temptation is always to presume the more likely option. So how do we recognise the more dangerous orthopaedic problems, while avoiding over-investigation and over-referral?

First, it is important to know what is typical so that we can know what is atypical.  For example, irritable hip is usually seen from the age of one to six years old.  It can occur outside of that age range but is uncommon and so is diagnosed with an appropriate caution.

If a preschool child has a fall, the outcome is usually no injury or a fracture.  Sprains are uncommon in this age group because they are too flexible to easily strain a ligament to the point of injury.

Once we are familiar with what is both normal and common, it is important to know what the signs are of the common and expected, we need to know what should alert us to the more significant yet less common pathologies.  In other words, what are the red flags?

There are some red flags that are fairly reliable and these are listed here.

However some of the red flags that are listed elsewhere are rather contextual, proving the evil twin problem.  For example, Arthritis Research UK lists nocturnal pains as a red flag symptom (1) while NHS choices lists nocturnal symptoms as a typical feature of growing pains (2).  That is  why red flags will only get you so far.  Sometimes certain presentations are a set piece.  Here are a few examples:

A 12 year old presents with bilateral knee pain, worse on the right.  The pain is worse after sports and is particularly bad on stairs.  He is limping.  Both knees have full range of movement and no effusion.  The tibial tuberosity is swollen and tender in both knees.

This is Osgood-Schlatters disease.  Simple.  This problem of adolescence is more a biomechanical problem than a true disease process.  There is little that can be done for this problem apart from symptomatic treatment and a careful management of the balance between being active and being in pain.  An orthopaedic surgeon can't fix this problem unfortunately.

A 7 year old presents with a limp and pain in the hip.  There is no history of injury.  They are not unwell or febrile.  Simple analgesia has helped but the limp is still obvious.  Examination is normal apart from a reduced internal and external rotation of one hip.

There are various possible explanations for this presentation, however index of suspicion for Perthe's disease has to be very high.  The mysterious onset of symptoms that is typical of Perthe's diease makes it a difficult diagnosis.  The early recognition of the disease is further hampered by the tendency that children have to reduce activity instead of increasing their complaining.  Orthopaedic surgeons don't have a magic treatment for Perthe's but will do everything they can to reduce the progression of this difficult disease.  X-ray or referral at presentation is recommended for a patient like this.

A 13 year old presents with what they think is a knee injury.  They have had some left knee discomfort which was made much worse by running yesterday.  Today, the pain is significant despite analgesia and they have a marked limp.  The most notable clinical finding is that movements of the left hip are restricted by pain.

This could be a muscular or ligamentous injury.  However it is also possible that this young person has a slipped upper femoral epiphysis.  The growth plate in adolescents is at risk of fracture and the subsequent movement can cause permanent damage if not treated as soon as possible.  These presentations are tricky as they come with a story that sounds more like a straightforward soft tissue injury.  The important thing is to have a high index of suspicion and a low threshold for X-ray or same day referral.

Edward Snelson
@sailordoctor
Specialising in conjoined Meducaction

Disclaimer: Once again, many thanks to the team of orthopaedic surgeons at the Sheffield Children's Hospital. This concludes the planned mini series of paediatric orthopaedic posts but if you have further questions or simply wish to tell us your favourite orthopaedic surgeon joke, please post in the comments box below.

References

1. Foster E et al, Growing pains: a practical guide for primary care, www.arthritisresearchuk.org
2. Growing pains (recurrent limb pain in children), NHS choices website

Paediatric Orthopaedic Problems of the Legs Pt 1 - Greater love hath no colleague than to give guidance rather than a guideline

Last month, the paediatric orthopaedic surgeons at Sheffield Children's Hospital sent out a call for the Primary Care community to ask them questions about common presentations. Unsurprisingly many of the questions were regarding things to do with growing legs.  Although there seems to be a guideline for everything, there is none for such problems.  While it would be possible to make such a guideline, referral pathways vary and guidelines do not always apply to every child.

It is a common concern: Are my child's legs normal?  Much of the time, children’s legs seem to be a 'funny shape'.  The vast majority of the time, these legs are normal.  This is the problem with paediatrics though: for everything that is normal or benign, there is an evil twin.  A relatively rare problem that is neither normal nor benign.  These complex problems usually have a considerable overlap with the simple ones and so can be difficult to spot.

To break with convention, we've put together some guidance which should apply across all the common presentations of growing legs.  That way, clinicians have a framework that allows them to make an assessment, rather than a rigid decision tool that tells people what to do and what not to do.  How refreshing!

The first thing to cover, is what is normal in growing legs.  As a general rule, things start to point out, then in and then straighten up as a child grows into their adult body.  

Fig 1. From birth, children's knees will tend to go into varus and then valgus before becoming a normal adult shape.  Bandy legs (also called bow legs) are therefore expected in a child under the age of three and knock knees are considered normal until roughly 8 years old.  Genu valgum may persist into adolescence without any need for intervention.

The other simple rule of thumb is that normal legs are symmetrical, function normally and are not associated with any other abnormality.  This applies to pretty much every scenario - Genu valgum, genu varus, in-toeing, flat feet, hypermobility, "growing pains" and tiptoe walking.

In general terms, the following presentations are normal unless there is reason to think otherwise (see red flags above):

• Bow legs (genu varus), in a child up to the age of 2 years

• Knock knees (genu valgum), in a child up to the age of 3 years or up to the age of 10 if resolving

• In-toeing gait (also called pigeon toe) up to the age of about 9

• Flat feet on weight bearing

• Tip toe walking in toddlers

• Hypermobility

The lovely thing about all of them is that the history and examination required is usually brief.  It is rare to need to refer or investigate.  What's wrong with  this child's legs?  Usually nothing, but more on that in the next GPpaedsTips post.

Many thanks to the paediatric orthopaedic team at Sheffield Children's Hospital for taking the time to answer questions and to turn their expertise into guidance.  At a time when Primary Care Guidelines are often written by Secondary Care clinicians, I find it most refreshing that someone is willing to give their time to share insights and provide general guidance which facilitates rather than dictates management in Primary Care.

Edward Snelson

The Hitchcock of Free Open Access Medical Education

@sailordoctor

Disclaimer:  All of the above is based on a standard number of legs.  For any variation on two legs, discuss with your local orthopaedic surgeon or possibly a vet.

Why has no one told me this before? Confirmation bias - It lies to you. It lies to everyone. What has it been telling you about children? (Part 1)

Recently, after I had explained why something was a medical myth, a colleague in Primary Care looked at me and with genuine exasperation said, "Why has no one told me this before?"

Good question.  The answer to this is complicated.  A lot of the time there is a big 'Emperor's New Clothes' factor.  Declaring a myth to be untrue requires someone to burst the bubble and it is not always the case that someone is listening or that anyone wants to change their belief.

Myths start for various reasons but only persist if they are fed.  For example, very few people actually believe in the existence of fairies.   Seeing a fairy or hearing from someone who claimed to see one might change that.   People do however believe that mice like cheese without any good evidence to support this.  Where does this belief come from?  Surely we can't all have taken Tom and Jerry cartoons at face value?  Since there was never any reason to doubt what we were told we continued to believe it. Well, it turns out that, whatever the basis for the belief, it is wrong when tested scientifically (Yes, this has been researched and published!).

The best ingredients for a myth are plausibility and confirmation.  Take the old chestnut about not being allowed to use adrenaline with anaesthetic in fingers as an example.  This myth originated when lidocaine and adrenaline were commonly mixed with various things to aid anaesthesia and asepsis.  The mix often contained cocaine, procaine and boric acid.  When skin necrosis developed in fingers, the cause was not isolated, but the idea that a vasoconstrictor (adrenaline) was the cause was credible.  In fact, the other ingredients were probably to blame.  Thus a myth  has persisted for roughly a century was created by a plausible theory and repeated episodes which seemed to confirm this theory. (1)

Confirmation bias comes in several forms.  It affects how we search for, interpret and retain information.  They have been responsible for misleading us about quite a few things in paediatics.  There are so many, in fact, that it would be ambitious to put them all in a single post.  Instead I will divide them roughly into two groups - those where we have been misled about cause and those where we are misled about effect.

• We tend to consider what the cause of something is when we witness an event.  
• We concentrate on an effect when we think we can influence events.

For now, I am going to run through some examples of presumed cause.  Lets start with the things that you may have been told are caused by something else, but probably are not.  It works like this:

Of course sometimes, the presumed cause is real.  We have confirmation bias for a reason and in most cases it is teaching us, not lying to us.  Assumption has a bad name for itself, but is a necessary part of how we work and learn.

(No disrespect to Mrs. Sullivan, who taught me that to assume makes and ass of you and me.  Mrs. Sullivan was an English teacher and the spelling mnemonic is valid even if the statement is completely wrong in the context of exploratory learning.)

In certain circumstances, the reality is very different from our assumptions.  This is usually due to a factor that is not as obvious as the two that we have associated.

There are several examples of this below.  The one that often surprises many people is finding out that it is a fallacy that fever causes febrile convulsions.  I know, right?  I mean it's in the name and everything!  It makes sense that fever causes febrile convulsions since a child develops a fever and then has a convulsion.  We even see a correlation between febrile convulsion and fever that comes on particularly quickly (or so we think).

The only problem is that the evidence goes against this being true.  When children are treated for their fever, it seems that they have the same number of fits.  (2) So what is the cause of the fits?  Probably badness.  Badness is the stuff that infections make which causes the fever, the flu symptoms and all that.  You know, chemicals and stuff.  So even when we treat the symptoms of the infection, badness still causes the seizure to occur.  We can't get rid of viral badness.  In most cases we just make children feel better until they make themselves well.

How does this change our practice?  When I found this out, it completely changed my approach to children who had suffered a febrile seizure.  I no longer worry that treatment needs to be focused on the fever rather than the child's wellness.  Most importantly, I now tell parents that the seizure was not preventable.  Often, the parent blames themselves for failing to treat the fever adequately.  They need to know that this convulsion was not their fault.


Next up is the apparent epidemic of allergy to amoxicillin.

We have to work this one backwards from the evidence.  Approximately 95% of children who have a label of amoxicillin allergy have no allergy when tested or challenged. (3) The explanation for this poor correlation is that children of a certain age frequntly develop a rash (which is often urticarial) while ill with a virus.  Viral and bacterial infections are difficult to tell apart, so it is not uncommon for a child to be given antibiotics while unwell with a viral illness.  When a culprit is sought for the rash, the antibiotics may be blamed, though the reality was that the virus caused it.

Finding this out completely changed my practice.  By careful case selection, I take every opportunity to undiagnose penicillin allergy.


Next up: another much maligned medicine - Ibuprofen.   Ibuprofen is often avoided in children who have history of wheeze.  I suspect that this is one of the biggest cases of (wrongly) presumed cause currently in paediatric practice.  You may have been told that ibuprofen causes wheeze or that ibuprofen should be avoided in children with a history of wheeze.  Well, it turns out that this is another myth that has persists despite being disproved.

Once again, the association in space and time of the medicine and the symptoms leads to a very rational fear that it is the ibuprofen causing the wheeze.  When large groups are studied, it seems that Ibuprofen may even be protective against wheeze. (4)  I'll just leave that one with you for a minute...


So after that bomb shell, something a little more palatable but still interesting.  Growing pains are not caused by (wait for it........) growing.  In fact no one knows what causes children to have growing pains.

Feel free to file this under 'how does that change my practice?'  I just think that it is interesting that we feel the need to have an explanation for a symptom which has no known cause and no effective treatment - a bit like colic really!


Next up is something a bit more meaty.  Based on the sessions that I do for GPs here and there, I would approximate that roughly three quarters of primary care clinicians are aware that there is a concern about using ibuprofen for children with chickenpox.  I also know that the basis for this concern is poorly understood.

The truth is that this concern was raised based on a cluster of cases of children who developed severe complications of secondary infection about 20 years ago (5).  No causal link has ever been convincingly shown and the fact that huge numbers of children continue to have ibuprofen in this context makes me think that more robust evidence would have emerged if there was genuine cause and effect.

Invasive streptococcal infection during varicella infection is something that all clinicians should know about.  It is also true that most children who have chickenpox are not very unwell and so paracetamol should be all that is needed.

So why does this matter?  It matters when someone is blamed for something based on poor evidence.  So, let's be clear.  The Emperor appears to be naked, but if anyone else can see that he's got clothes on, I am prepared to be convinced.

Edward Snelson
@sailordoctor
Non-steroidal guardian of the year 2014-2016

Disclaimer- I would never use any of the treatments listed above.  For many years now I have only used fairy magic to treat my patients and any prescribed medication is a pretence.  No one can prove to me that fairies don't exist. 

References

1. Bradon et al, Do Not Use Epinephrine in Digital Blocks: Myth or Truth?, Plastic & Reconstructive Surgery, February 2001
2. A Sahib El-Radhi, W Barry, Do antipyretics prevent febrile convulsions?, ADC, Volume 88, Issue 7, 2003
3. Caubet JC et al., The role of penicillin in benign skin rashes in childhood: a prospective study based on drug rechallenge, J Allergy Clin Immunol. 2011 Jan;127(1):218-22.
4. Kanabar et al., A review of ibuprofen and acetaminophen use in febrile children and the occurrence of asthma-related symptoms, Clinical Therapeutics, Volume 29, Issue 12, December 2007, Pages 2716-2723
5. Zerr DM. et al., A case-control study of necrotizing fasciitis during primary varicella, Pediatrics. 1999 Apr;103(4 Pt 1):783-90.

If it isn't broken

Minor injuries in children are common.  Quite often, parents will present their children to General Practice, a Minor Injury Unit or an Emergency Department seeking reassurance.  This is often possible without the need for any investigations.  This post will explore some of the general principles of assessing and treating minor injuries in children.  I hope that by understanding some of the subtleties of how children's injuries work you will feel a bit more confident about managing these injuries when appropriate.  Over the next few weeks, there will be a smattering of posts that give specifics about injured body parts.  First, as my science teachers told me, we must return to first principles.

1.  Children injure themselves in different ways to adults

In fact, each part of childhood has a different pattern of injuries.  The main reason for this is engineering.  Children's bones are less brittle, especially when they are very young.  They are also very flexible creatures.  The combination of these mean that sprains are far less common in the under five year olds.  It also means that small children can fracture bones with seemingly innocuous injuries.  The best example of this is the toddler's fracture, which can occur with a simple tumble from running.

2.  Small children may not localise injuries well

There are several reasons for this and nobody really knows what they are.  I suspect that it is a combination of not being aware of specific body parts (have you ever seen a 3 year old draw a person?) and basic stupidity inherent to being a small child.  Whatever the reason, it is wise to look at least one joint above and below the reportedly injured part before deciding what to do.

3.  It is particularly desirable to avoid radiation in children

Because children are more susceptible to the dangers of X-rays, unnecessary radiation should be avoided.  X-rays should be done if there is a good chance that they will change management.  They should not be done for reassurance or as part of defensive medicine.

4.  If a child has normal use of the limb after analgesia then they are very unlikely to have a significant injury.

The ability to move a joint well is a good rule out (for the exception to this, see below), but persistent pain after analgesia does not always mean a treatable injury.

5.  Some children perceive and respond to pain differently.

Children with neurological or developmental problems including ADHD and ASD are more capable of having significant fractures despite seemingly normal limb function.  These children require a higher index of suspicion and a more interventional approach.

6.  Sometimes, the injury is not an injury (as such)

Amazingly, young people often ignore niggling pains.  They do so until whatever is a problem is suddenly made worse through exertion or an injury.  For this reason, some things that present as injuries are more significant and long term problems.  That doesn't mean that you have to disbelieve every injury.  However if something is slow to resolve or doesn't fit then it is wise to look again.  There are certain presentations, (e.g. as adolescents with hip pain after an injury) that should always be investigated carefully.

7.  The injury should fit the mechanism

This applies for several reasons.  The one that most will think of is the issue of safeguarding.  However it is equally true that when the mechanism does not really explain the injury, there may be a medical reason for this.  For that reason, keep an open mind. (Ref Shrodinger's Safeguarding)

Assessing and treating minor injuries in children is relatively straightforward and rewarding.  If you know what to look for and what the pitfalls are, it is often possible to be pragmatic.  Investigations are not always necessary and children heal quickly, given the chance.

GPpaedsTips is written for clinicians.  We all have to work within our own competencies.  However I don't think that minor injuries are more complicated than minor illness in children.

If it isn't broken give them analgesia and a sticker.  But how do I know????   That's easy.  Sometimes you just know because the child shows you how uninjured they are, sometimes it doesn't necessarily matter (that will be covered in the specific injury posts coming soon) and sometimes I doubt myself and do an X-ray.  And that's fine too.

Edward Snelson
@sailordoctor

Disclaimer: On no account is anyone to ask my children about my ability to recognise a significant injury.

This post is the first in a series of posts about injury.  Click these links to read about specific injuries and when to treat, refer etc. -

• Head injuries
• Finger injuries
• Pulled elbows

Is this really an injury or something else?

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