Slipped capital femoral epiphysis: an ultrastructural study before and after osteosynthesis.

Background and purpose Several different theories have been proposed to explain the pathogenesis of slipped capital femoral epiphysis (SCFE). Using transmission electron microscopy (TEM), we carried out an ultrastructural study of core biopsy specimens of the physis at various stages of the disease. Methods Core biopsies were performed in 6 patients with different forms of SCFE during the first operation, and in 3 of them when removing the osteosynthesis material before physeal closure. The specimens were prepared for TEM examination. Results In 6 specimens obtained at first surgery, a marked distortion of the physeal architecture was observed. In 2 of the 3 specimens obtained at removal of the osteosynthesis material, the physis showed a more normal organization. Interpretation The improvement of the pathological alterations observed in the 2 cases after surgical intervention leads us to consider the possibility that when the growth plate is stabilized directly by pinning or indirectly by creating more optimal loading conditions with an intertrochanteric osteotomy, the morpho-functional characteristics of the physis can be restored and its growth process may resume.