Introduction: Treatment of acetabular defects can be difficult, especially in case of roof destruction. Since 9 years, we use a variant of Paprosky’s technique which consists in rebuilding the roof by structural allograft and acetabular reinforcement ring. The purpose of this study is to present this technique and the follow up results.

Patients: This retrospective study concerns 21 patients (23 hips) with severe acetabular bone loss (8 cases of stage 2 and 15 cases of stage 3 of Paprosky): 4 septical and 19 aseptical loosening. Between 1998 and 2005, all patients were operated with the same surgical technique using an allogeneic structural allograft (femoral head or distal femur) and an acetabular reinforcement ring (20 of KERBOULL, 3 of GANZ) associated with a cemented PE cup.

Method: Review included a clinical and X-ray evaluation (analysis of the refocusing of the hip, the positioning and the stability of implants and the graft incorporation).

Results: Mean duration of follow-up is 3,5 years [1–8,3]. Preoperative PMA score rised from 6,6 [0–12] to 15,8 [12–18] in postoperative. There was no peroperative complication. After surgery, 2 cases of early hip dislocation required PE block; 2 cases of sepsis were treated, one by washing and one by a surgical revision. In 60% of cases, immediate total weight bearing was allowed.

The immediate postoperative X-rays showed that the rotation center of the hip was 5,2 mm [0–10] far from the ideal rotation center (26% of cases: 0 mm) and the PE cup was implanted with a lateral inclination of 42,5° [30–55]. In postoperative X-ray follow up, one case of acetabular aseptic loosening was found which didn’t need hip revision. In all other cases no modification of implants position neither of hip rotation center was noted. In 79% of cases, we had total graft incorporation; in 17% of cases, an non evolutive radiolucent area between graft and bone and in 4% of cases (loosening) a graft migration.

Conclusion: The use of a structural allograft combined with acetabular reinforcement ring allows hip reconstruction in severe acetabular bone loss with good medium term results.

Purpose: The Harrington instrumentation without vertebral grafting associated with corset treatment was described by Joe Moe in 1978 for the treatment of severe scoliosis in young children. In 1989, Jean Dubousset described the ratchet-brace process which occurs after isolated posterior vertebral grafting performed before the end of growth. Thus several options should be discussed for young children with a severe evolving scoliosis inaccessible to orthopaedic treatment: a subcutaneous rod to be lengthened repeatedly without grafting, anterior epiphysiodesis fusion, or a combination of these methods. The purpose of this retrospective analysis was to examine the posterior approach using a subcutaneous rod without grafting.

Material and methods: Fourteen children with scoliosis were treated over a ten-year period: infantile spinal amyotrophy (n=10), cerebral palsy (n=3), congenital (n=1). Mean age at the first operation was 8.6 years. Mean preoperative Cobb angle was 72.5° (45–105°). From the third case onward, the treatment protocol was the same for all patients using proximally three hooks on three thoracic vertebrae mounted on a rod and distally two hooks (L4-L5) mounted on a second rod. The two subcutaneous rods were connected with a connecting device and the fusion grafts were inserted. The first lengthening was planned at about six months. Further lengthenings were planned for about once a year until Risser 2 when spinal fusion could be undertaken.

Results: The first operation corrected the curvature to 43.7° (28–70°) On average, four lengthenings were performed before definitive fusion. Each lengthening (mean 13.7 mm (10–20) produced an average 16.4° (4–31°) correction. Mechanical complications (one proximal hook pull out, one rod fracture) occurred during the learning period (first patient) before the present technique was instituted.

Discussion: The absence of mechanical complications with the described method and the quality of the results suggests this technique should be pursued, avoiding the anterior approach in certain patients where respiratory function is compromised. The inconvenience of the annual operations for lengthening may be avoided with the self-lengthening Phenix #1666 rods.