#MiniTeach: A Limping Teenager

"A 13-year-old boy presents to ED having fallen off his scooter complaining of a painful limp."

He was seen by his GP 2 weeks prior to this with similar pain and was diagnosed with a groin strain.

1. What would you look for on clinical examination?

Look – is he weight-bearing? Any scars, swelling, skin changes? (specifically, does he have a limp or is he out-toeing?)

Feel – Any palpable tenderness, warmth?

Move – Passive and active. Does he have reduced painful internal rotation and reduced abduction?

2. What might you consider in the differential diagnosis?

Groin strain

Slipped Upper Femoral Epiphysis (SUFE)

Osteitis pubis

Osteomyelitis

Septic arthritis

Stress fracture/pelvic fracture

Avascular necrosis

3. What does the X-ray show?

The X-ray, although subtle shows a left-sided slipped upper femoral epiphysis = SUFE.

The classic X-ray sign of this is that the femoral head looks like a ‘melting ice-cream’. (This is more obvious in this case on the post-operative films). More subtle SUFEs need to be assessed using Kline lines. (see the further reading section).

4. What are the risk factors for this condition?

Boys are three times more likely to get this condition than girls.

The peak onset is early teenage years (age 13) (although girls tend to get it a little younger due to earlier puberty – age 11).

It is commoner in the left hip than the right

It is bilateral in 20-40%

There is the possibility of a genetic susceptibility.

Obesity

Endocrine disorders

5. How should the patient be managed?

Analgesia

Follow the limping child pathway

If suspected – bed-rest and refer to orthopaedics for surgical fixation

6. What are the complications of this condition?

Avascular necrosis of the femoral head

Chondrolysis (degeneration of the articular cartilage)

7. What is the Southwick Angle?

This is a radiographic angle used to measure the severity of a SUFE.