Page 26 - Slipped Capital Femoral Epiphysis Pathogenetic and Clinical aspects

Chapter 2
thigh or knee. The radiographs show no physeal slippage but might reveal a minor widening and fuzziness of the physis. Patients with symptoms less than 3 weeks old are defined as having acute SCFE. On the AP and lateral radiograph of the proximal femur, there is an abrupt slip of the physis visible. Patients with more than 3 week old symptoms are defined as having chronic SCFE. This accounts for 85% of all slips. The radiographs can show a variable amount of remodelling of the femoral neck. Patients with acute on chronic SCFE have pre-existent pain but the pain has aggravated acutely within the last 3 weeks.
The Loder classification is based on either the ability to walk with or without crutches on the affected hip (stable) or not (unstable). This classification is a prognostic classification, the unstable group having a higher incidence of avascular osteonecrosis of 47% [71].
Ziebarth et al. [164] evaluated the clinical classifications for acute and acute on chronic as well as an unstable hip intraoperatively, by identifying an intact or disrupted stability of the femoral head in situ. Interestingly, these clinical observations inaccurately identified the intraoperative mechanical stability.
The radiological (Southwick-angle) classification describes the amount of slip on a frog lateral radiograph of the proximal femur of the hip. The Southwick angle is the line perpendicular to the connecting two points at the posterior and anterior tips of the epiphysis at the physis. A third line is drawn down the axis of femur. Angles are classified as severe, modest and mild at > 50 degree, 30 to 50 degrees and below 30 degrees respectively [133].
In conclusion there are three ways of classification of SCFE, based on history, clinic and radiograph. The clinical and radiographical classifications can be used for prognosis of SCFE.
Treatment.
The ideal treatment for SCFE is defined as the treatment that has the best outcome for the hip joint, while taking into consideration the complications that can occur with the different treatments options, aiming for a good long-term follow-up result. Management of SCFE is controversial and only level 4 and 5 evidence exists [156]. Treatment options appear more subject to a surgeons’preferences and experiences than to evidence of superiority of a particular treatment. Avoiding the potential complications like progression of the slip, chondrolysis and avascular necrosis is probably the most important initial goal in the treatment of SCFE [69].
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