THE VONROSEN SPLINT COMPARED WITH THE FREJKA PILLOW - A STUDY OF 408 NEONATALLY UNSTABLE HIPS

101 children in Tromso, Norway, treated with the Frejka pillow for 4.5 months because of neonatal hip instability (NHI) were compared with 307 children in Malmo, Sweden, treated with the von Rosen splint for 3 months. The pelvic radiographs, taken when the treatment was terminated, were as assessed by the acetabular index (Al) and the cases of failure were evaluated. The Al showed no difference between the two groups. The Frejka group had 4 patients who received further treatment because of remaining acetabular dysplasia and/or subluxation while the von Rosen group had none. The difference in risk of failure might partly be explained by different criteria for failure.