THE TORSIONAL BASIS FOR SLIPPED CAPITAL FEMORAL EPIPHYSIS

Fifteen moderate to severe acute slipped capital femoral epiphyses wer e manipulated in 15 patients to correct significant deformities; in ea ch case, torsion played a critical role in the reduction. Nine of 15 p atients with acute slips underwent controlled, open reduction from the anterolateral approach, stabilizing the epiphysis while the metaphysi s was internally rotated, flexed, and abducted; none had osteonecrosis or chondrolysis. The other 6 acute slips were treated with traction u sing internal rotation to achieve closed reduction; 2 of these 6 close d reductions progressed to osteonecrosis, and both were reduced in an uncontrolled situation. Of the 15 acute slips, 6 involved torsion as t he primary force. Based on the importance of torsion in all the reduct ions and the prevalence of torsion as an etiologic factor in the initi al slips, it is postulated that torsion is an important contributing c omponent in the etiology of slipped capital femoral epiphysis. Despite 2 cases of osteonecrosis in unstable hips, these 15 manipulative redu ctions were 87% successful. If the 2 inadvertent closed reductions are eliminated, then the success rate is 100%.