Slipped upper femoral epiphysis

Case contribution: Dr Radhiana Hassan

Clinical:

  • A 16 years old boy
  • History of fall during football game
  • Complaint of left hip pain which was progressive associated with limping gait.
  • On examination; flex left hip, abducted and externally rotated.
Pelvis radiograph AP view

Radiographic findings:

  • There is lateral displacement of the left proximal femur metaphysis, with widening and irregularity of left physis (yellow arrow).
  • Positive Threthowan sign is seen, in which the Klein line does not intersect with the left femoral epiphysis (red line). Compare to normal appearance on right side (white dotted line)
  • There is also disruption of the Shenton’s line (dotted red line). Compare to normal line on the right side (white curve line).
  • Positive metaphyseal blanch sign is noted, in which appearance of sclerosis of the metaphysis (due to overlap with the posteriorly displaced epiphyses).
  • Left femoral epiphysis appear slightly smaller than the right side.
  • The hip joint itself is otherwise normal.
  • No flattening of the femoral head.

Diagnosis: Slipped upper femoral epiphysis

Discussion:

  • Slipped upper femoral epiphysis is also called slipped capital femoral epiphysis.
  • It is commonly affecting adolescents
  • More common in boys than girls
  • Obesity is a significant risk factor
  • Other risk factors include hypothyroidism, hypopituitarism, hyperparathyroidism, renal osteodystrophy and radiation/chemotherapy
  • Radiological findings include:
    • The affected epiphysis appears smaller due to posterior slip
    • Line of Klein fails to intersect the epiphysis (Trethowan sign)
    • Loss of triangular sign of Capener ( metaphysis do not overlap with posterior lip of acetabulum)
    • Metaphyseal blanch sign; increased density of proximal metaphysis due to superimposition of the femoral neck and posteriorly displaced capital epiphysis
  • Treatment: surgical stabilization
  • Complications:
    • Osteoarthritis (90%)
    • Avascular necrosis of the femoral head (10-15%)
    • Chondrolysis (7-10%): acute cartilage loss
    • Deformity-limb length discrepancy
    • Femoroacetabular impingement

Progress of patient:

  • Screw fixation done
  • Uneventful recovery
  • Able to play sport again
Pelvis radiograph AP view post surgical intervention

 

Author: radhianahassan