Intertrochanteric corrective osteotomy for moderate and severe chronic slipped capital femoral epiphysis.

A total of 299 acute, acute on chronic, and chronic slips were treated from 1975 to 1997. The patients were reviewed in three cohorts: 75 patients with slipped capital femoral epiphysis (SCFE) were treated between 1975 and 1982, 101 patients with 107 slips were treated from 1983 to 1991, and 110 patients with 117 slips were treated from 1992 to 1997. The authors have corrected 130 hips with chronic slips by intertrochanteric osteotomy. Of these 130 hips, 111 were moderate slips between 20 and 50 degrees, 19 hips with a slipping angle of more than 50 degrees were classified as severe chronic slips. During the same period, 92 chronic slips less than 20 degrees were treated by fixation in situ, and 77 acute or acute on chronic slips had an open and exceptionally a closed reduction followed by fixation. Eight postoperative fractures caused by inadequate plate fixation were observed after these 130 intertrochanteric osteotomies. They all necessitated plate replacement followed by uneventful healing. Three patients with major displacement developed chondrolysis after the corrective osteotomy, two were transient, and one patient developed avascular necrosis (AVN). The midterm clinical results showed a satisfactory outcome in all three cohorts. In 47 patients in the series from 1975 to 1982, the clinical outcome was measured using Imhäuser's score: 43 patients had good and very good results, 4 patients had a moderate or bad result. In the second and third series, the IOWA hip score was used to measure the clinical outcome. The 49 patients with osteotomies for chronic slips treated from 1983 to 1991 had an average score of 90.3 points, and 1 patient had AVN. In the latest series from 1992 to 1997 with 34 corrective osteomies, there was no chondrolysis or AVN and the average IOWA score was 93.9 points.