Residual hip growth after pinning of slipped capital femoral epiphysis.

Screwing of slipped capital femoral epiphysis must prevent its further slipping by prematurely fusing the physis. Whichever material is used, persistent femoral growth has been described, thereby increasing the risk of bone deformation. The objective of this study is to evaluate the residual growth after screwing of slipped capital femoral epiphysis. This study concerned 26 children, among which 13 children have been included, and 13 children excluded because of an incomplete clinical or radiological follow-up, or treatment by another technique. The pathological hip was treated with one screw (in eight cases) or two screws (in five cases). The controlateral hip was fixed with one screw. The different measures were taken on anteroposterior radiographs done the days after surgery, and on the first radiograph on which the growth plate had fused. Growth plate fusion was obtained after an average of 20 months. Each patient had presented a residual growth of at least one hip, thus 85% of the 26 fixed screws. Among the four hips, which did not grow, three were pathological, and were fixed by one screw (in one case) or two screws (in two cases), in a central or medial position. There was not any statistical relationship between the growth persistence and the other studied criteria. These results, proving the growth persistency, suggest that the follow-up must be extremely careful, as the number of threads crossing the growth plate will decrease, with the risk of loss of mechanical stability and reappearance of the femoral epiphysis slippage.