In short
Growing pains are common, harmless and have a recognisable pattern: both legs, in the evening or at night, in the muscles rather than the joints, with a completely normal child by morning. Pain that falls outside that pattern — a swollen joint, a limp, morning stiffness, fever — is not growing pains and needs assessing.
Children complain of leg pain often, and the great majority of the time it is nothing. The difficulty is that juvenile arthritis is uncommon enough that it is rarely the first thought, and it does lasting harm when it is missed — including damage to growing joints and, in some forms, silent eye inflammation that threatens sight.
The useful approach is not to worry about every ache. It is to know the pattern of ordinary growing pains well enough to recognise when something does not fit.
What growing pains look like
The classic picture, usually between three and twelve years old:
- Both legs. Thighs, calves, behind the knees.
- Evening or night. Often wakes the child, who is distressed and wants rubbing.
- In the muscles, not over a joint. The child cannot usually point to a single spot.
- Gone by morning. This is the most reliable feature. The child wakes and runs about normally.
- No swelling, no limp, no fever, no rash.
- Responds to massage, warmth and reassurance.
The name is a misnomer — they are not caused by growth — but the pattern is well described and genuinely benign.
What does not fit, and matters
Take the child to a doctor if any of these are present:
- A swollen joint. One knee visibly larger than the other is the single most important sign. Children do not complain much about it, so it is often spotted by a parent while the child is in shorts.
- A limp, especially in the morning, improving as the day goes on. The reverse pattern of mechanical pain, and strongly suggestive of inflammation.
- Morning stiffness. A child who is slow and awkward on getting up and loosens after half an hour. Young children rarely say "stiff" — they ask to be carried, or go back to crawling.
- Pain in one place consistently, particularly in one joint.
- Fever, especially recurring, with rash or feeling generally unwell.
- Weight loss, night sweats, pallor or bruising. These need urgent assessment, because leukaemia can present with bone and joint pain in children and must be excluded.
- Pain that wakes the child and is still there in the morning.
- Refusal to use a limb, or regression in skills previously mastered.
- A red, hot joint with fever — this is an emergency, not an appointment.
What juvenile idiopathic arthritis is
Juvenile idiopathic arthritis (JIA) is the commonest chronic inflammatory arthritis in children: arthritis beginning before the age of sixteen, lasting more than six weeks, with no other cause found. It is not childhood rheumatoid arthritis, and it is not one disease — several subtypes behave quite differently.
- Oligoarticular — four or fewer joints, often a single knee or ankle, in young girls. The commonest form, and the one most associated with silent eye inflammation (uveitis), which causes no pain and no redness and can damage sight before anyone notices. Children with this form need regular slit-lamp eye checks by an ophthalmologist, on a schedule, regardless of symptoms. This is the single most important fact in this article.
- Polyarticular — five or more joints, often small joints of the hands, more like adult rheumatoid arthritis.
- Systemic — spiking fevers, a salmon-pink rash that comes and goes with the fever, enlarged lymph nodes and liver or spleen, with arthritis sometimes appearing later. The child looks unwell.
- Enthesitis-related — more often older boys, with pain where tendons attach, especially at the heel, and sometimes back and sacroiliac involvement. Related to adult axial spondyloarthritis, and often HLA-B27 positive. Heel pain and enthesitis covers the adult version.
- Psoriatic — arthritis with psoriasis, nail pitting, or a whole swollen finger or toe.
What else causes joint pain in children
- Reactive arthritis after a throat, gut or urinary infection — usually settles over weeks. See reactive arthritis.
- Transient synovitis of the hip — a limping child after a viral illness, settling in days. Common and benign, but hip infection must be excluded first.
- Septic arthritis and osteomyelitis — hot joint, fever, a child who will not move the limb. Emergency.
- Hypermobility — flexible joints with aching after activity, often a family trait. Helped by strengthening.
- Overuse injuries in sporty children, such as Osgood-Schlatter at the knee.
- Vitamin D deficiency, common in Indian children with limited sun exposure, causing bone pain and muscle weakness.
- Leukaemia, which is uncommon but must be considered when there is bone pain at night, pallor, bruising, fever or weight loss.
What happens at the appointment
Examining a child's joints is a different skill from examining an adult's, and a good deal of it is done by watching the child walk, climb, and play rather than by formal testing.
Investigations depend on what is found. A blood count, ESR and CRP are usual; antibodies such as ANA are used for assessing uveitis risk rather than for diagnosis. What a positive ANA means is worth reading, because the test causes a great deal of unnecessary alarm in children. Ultrasound is useful for confirming joint swelling.
JIA is a clinical diagnosis. No blood test confirms it, and normal tests do not exclude it — the same principle as joint pain with normal blood tests in adults.
Why the delay matters
Untreated inflammatory arthritis in a child affects growth as well as joints — a persistently inflamed knee can cause one leg to grow longer than the other, and jaw involvement can affect facial development. Uveitis can damage sight before anyone knows it is there.
Treatment is effective and has changed a great deal in twenty years. Many children reach remission and lead ordinary lives, with normal sport and schooling.
School, sport and daily life
Parents ask two questions once a diagnosis is made, and both deserve a clear answer.
Should they stop sport? Almost never. Children with well-controlled arthritis are encouraged into normal activity; exercise maintains muscle, protects joints and matters for bone development. What is adjusted is timing during a flare, not participation in general. Swimming and cycling are easy on joints and good defaults when a knee is grumbling.
What does school need to know? Usually a few practical things rather than a medical history: permission to move during long periods of sitting, extra time or a scribe when hands are affected during a flare, a second set of books to avoid carrying a heavy bag, and somewhere to take medicines if needed. Morning stiffness also makes early classes genuinely difficult, which teachers interpret as slowness unless told.
Most children with modern treatment do all the things their classmates do.
What to do as a parent
If the pattern fits growing pains — both legs, evenings, normal by morning, no swelling — reassurance and massage are the right response.
If anything does not fit, particularly a swollen joint or a morning limp, get it looked at. Photograph the joint, note the time of day the symptoms occur, and take that with you. An appointment that ends in reassurance costs an hour. The alternative costs considerably more.
If you would like a child's joints assessed, you can request a callback or book a consultation.
Common questions
How do I know if it is growing pains or arthritis?
Growing pains affect both legs, come in the evening or at night, sit in the muscles rather than over a joint, and leave the child completely normal by morning. Arthritis more often involves a swollen joint, a limp that is worse in the morning and improves through the day, and stiffness on waking.
At what age do growing pains occur?
Most commonly between three and twelve years. They are not actually caused by growth, and they do not occur during growth spurts specifically, but the pattern is well described and harmless.
My child limps in the morning but is fine later. Is that normal?
No. That pattern — worse on waking, easing with movement through the day — is the hallmark of inflammation rather than injury or growing pains, and it should be assessed. A young child may show it by asking to be carried rather than by complaining of stiffness.
Can children get arthritis?
Yes. Juvenile idiopathic arthritis begins before the age of sixteen and lasts more than six weeks. It is not rare enough to ignore, and it is treatable. Several subtypes exist, affecting anything from a single knee to many small joints.
Why do children with arthritis need eye checks?
Some forms, particularly the type affecting four or fewer joints in young girls, carry a risk of uveitis — inflammation inside the eye that causes no pain and no redness. It can damage sight before anyone notices, so regular slit-lamp examinations are done on a schedule regardless of symptoms.
When is a child's joint pain an emergency?
A hot, red, swollen joint with fever, or a child who refuses to move a limb, needs assessing the same day — joint infection destroys cartilage quickly. Bone pain at night with pallor, bruising, fever or weight loss also needs urgent assessment.
Sources
- NHS — growing pains www.nhs.uk
- NIAMS — juvenile arthritis www.niams.nih.gov
- MedlinePlus — juvenile arthritis medlineplus.gov
- NHS — septic arthritis www.nhs.uk
This article is general information and does not replace a consultation.