Slipped upper femoral epiphysis (summary)

This is a basic article for medical students and other non-radiologists

Slipped upper femoral epiphysis (SUFE), also known as a slipped capital femoral epiphysis (SCFE),  is a relatively common condition affecting the physis of the proximal femur in adolescents. It is one of commonest hip abnormalities in adolescence and is bilateral in around 20% of cases.

Reference article

This is a summary article. For more information, you can read a more in-depth reference article: slipped upper femoral epiphysis.

Summary

• epidemiology
  • more common in boys than girls, Afro-Carribeans than Caucasians
  • boys present later than girls
  • obesity is a significant risk factor
• presentation
  • hip pain progressing to limp
• pathology
  • widening of the physis during rapid growth
  • repeated trauma, especially in obese adolescents
• radiology
  • pelvic radiograph (AP and frog-leg lateral) demonstrate slip in most cases
• treatment
  • progression towards surgical treatment
  • SUFE is bilateral in 20% of cases
    • prophylactic pinning of the contralateral hip
• prognosis
  • long term degenerative osteoarthritis (90%)
  • femoral head AVN (10-15%)

Radiographic features

Plain radiograph

The slip is posterior and to a lesser extent medial. It is more easily seen on the frog-leg lateral view rather than the AP hip view and as it moves posteriorly, it appears smaller.

On the AP, a line drawn up the lateral edge of the femoral neck (line of Klein) fails to intersect the epiphysis.

MRI

In the acute stage, marrow edema results in increased signal on T2-weighted sequences. Marrow edema is non-specific and while it may indicate early bone changes in SUFE, there are numerous other causes, e.g. infection or tumor.

MRI can be used to examine the contralateral hip which is important because of the high incidence of bilateral slip. 

CT

CT can be used to assess the degree of displacement in early disease, but should not be used unless absolutely necessary because of the radiation dose.

Ultrasound

Ultrasound may be performed in the assessment of hip pain. However, it should not be used as a replacement for a pelvic radiograph.​