Transient Synovitis (Irritable Hip)

What is transient synovitis?

Transient synovitis — sometimes called irritable hip — is a temporary inflammation of the hip joint that's most common in children aged 3 to 8. The exact cause isn't always clear, but it often follows a viral illness like a cold and tends to settle on its own within one to two weeks.

It's a benign condition in most cases, but the symptoms can mimic more serious problems — particularly septic arthritis, which is a hip joint infection. Telling the two apart is one of the most important parts of assessing a child with hip pain and a limp.

Most children with transient synovitis recover completely with simple measures.

What does it feel like?

The classic story is a child who suddenly starts limping or refusing to weight-bear, often a few days after a viral illness. Common features include:

• A limp or refusal to walk

• Pain in the hip, groin or sometimes referred to the knee

• Restricted hip movement, particularly internal rotation

• Mild discomfort but the child is otherwise generally well

• Symptoms that improve over days rather than getting worse

If a child is systemically unwell — high fever, lethargic, very tender — that pattern is more concerning and needs urgent assessment to exclude infection.

How is it diagnosed?

Diagnosis is largely about excluding other causes of hip pain. Examination, blood tests and ultrasound of the hip all play a role in distinguishing transient synovitis from more serious conditions.

Blood markers of inflammation are typically normal or only mildly raised in transient synovitis but significantly raised in septic arthritis. Combined with clinical features and imaging, this helps clarify the diagnosis.

Sometimes the picture is clear quickly; sometimes the child is observed to see how the symptoms evolve. Either way, the priority is making sure nothing more serious is being missed.

What are the treatment options?

Once the diagnosis is established, treatment is essentially supportive — rest, simple pain relief and gradual return to activity. Most children improve significantly within a week.

If symptoms don't follow the expected pattern of improvement, reassessment is important. Persisting or worsening symptoms warrant further investigation. Nev will work through the right approach for your child at your consultation.

When should you get it checked?

Seek prompt assessment if:

• Your child develops a limp or refuses to walk

• There's hip, groin or knee pain in a young child

• Your child is unwell with fever and joint pain

• Symptoms aren't improving within a few days

• You're unsure whether it's something simple or something more serious

A child with a hip and a limp deserves a clear assessment. The good news is that the most common cause is a benign one — but ruling out the more serious possibilities is what makes a thorough assessment so worthwhile.