Slipped Capital Femoral Epiphysis

  • Etiology: Posteromedial epiphyseal slip or Salter-Harris Type I fracture due to repeated trauma
  • Imaging Radiograph:
    — Pre-slip – earliest findings are mild widening of proximal femoral physis and offset of femoral head on frog-leg lateral view
    — Femoral head slips posteromedial (seen better on lateral view)
    — Line of Klein drawn over lateral aspect of femoral neck should intersect ~ 1/6 of femoral head
    — Make sure to image both hips for comparison purposes
    — 25% of cases are bilateral
  • Imaging MRI:
    — Physeal widening
    — Metaphyseal marrow edema adjacent to physis
    — Joint effusion
    — Synovitis
    — May or may not have epiphyseal displacement
  • DDX:
  • Complications: Osteoarthritis, avascular necrosis of femoral head, chondrolysis, femoroacetabular impingement, leg length discrepancy
  • Treatment: Surgically stabilized via screw without reduction of prexisting slip due to increased risk of post operative osteonecrosis associated with slip reduction
  • Clinical:
    — Presents with hip pain which progresses to limp
    — Seen in older (13 years old) versus Legg-Calve-Perthes (in 4-8 years old)
    — 25% bilateral
    — Risk factors – obesity and endocrine and delayed skeletal maturation and family history and hip trauma and decreased femoral anteversion

Radiology Cases of Slipped Capital Femoral Epiphysis

Radiograph and CT of slipped capital femoral epiphysis
AP radiograph of the pelvis (upper left) shows the left femoral metaphysis to be displaced laterally from its epiphysis. This is better demonstrated on the coronal CT without contrast of the pelvis (upper right) and 3D CT of the pelvis (below)
Radiograph and CT of slipped capital femoral epiphysis
AP radiograph of the pelvis shows a fracture through the left physeal growth plate causing the femoral epiphysis to sublux off of the femoral metaphysis. This is more clearly seen on the coronal 2D reconstruction CT of the pelvis.
Radiograph of slipped capital femoral epiphysis
AP radiograph of the pelvis (left) and AP radiograph of the left hip (right) shows left femoral head physeal widening, with the femoral head slipping posteromedially as evidenced by the line of Klein drawn over lateral aspect of femoral neck not intersecting any of the femoral head.
Radiograph of slipped capital femoral epiphysis
Frogleg radiograph of the pelvis shows a fracture through the right physeal growth plate causing the femoral epiphysis to sublux off of the femoral metaphysis.
Radiograph of Legg-Calve-Perthes disease and slipped capital femoral epiphysis
AP (above) and frogleg (below) radiographs of the pelvis shows the right femoral head to be flat and enlarged with femoral neck shortening. The left femoral epiphysis is slipped posteromedially.