To assess if Osteoset (CaSO4) improves graft incorporation after shelf procedure and whether spica immobilisation is necessary 49 patients with acetabular dysplasia treated by shelf procedure were reviewed retrospectively. Group 1 (19 children) and group 2 (12 adults) had shelf acetabuloplasty using autogenous bone graft and CaSO4. Group 3 (18 children) underwent shelf acetabuloplasty using autogenous bone graft alone. Group 2 was assessed separately to avoid age bias. Within group 3 we compared 10 patients managed in plaster for six weeks with 8 mobilized on crutches post operatively. Total shelf and graft area, total shelf length, extra-osseous shelf length and speed of graft incorporation were measured radiologically. There was no difference in shelf indices between patients treated in plaster and those mobilized on crutches. Use of CaSO4 significantly enlarged shelf volume by 3 months post-operative with less resorption, which was maintained throughout follow-up. In contrast the non-CaSO4 group showed a steady decrease in shelf volume. The extra-osseous shelf length was initially similar in groups 1 & 3. By 6 weeks the group 1 extra-osseous shelf was significantly greater than for group 3 and was maintained throughout follow-up. Graft incorporation was faster in group 1. Shelf area and extra-osseous shelf length improved significantly in group 2. However total shelf length decreased slightly by 6 months.Aim
Methods/results
We evaluated radiological hip remodelling after shelf acetabuloplasty and sought to identify prognostic factors in 25 patients with a mean age of 8.9 years (7.0 to 12.3) who had unilateral Perthes’ disease with reducible subluxation of the hip in the fragmentation stage. At a mean follow-up of 6.7 years (3.2 to 9.0), satisfactory remodelling was observed in 18 hips (72%). The type of labrum in hip abduction, as determined by intra-operative dynamic arthrography, was found to be a statistically significant prognostic factor (p = 0.012). Shelf acetabuloplasty as containment surgery seems to be best indicated for hips in which there is not marked collapse of the epiphysis and in which the extruded epiphyseal segment slips easily underneath the labrum on abduction, without imposing undue pressure on the lateral edge of the acetabulum.
