Combined, novel management of bilateral varus hip deformity using "Eight-plate" in children with spondyloepiphyseal dysplasia congenita

Spondyloepiphysal dysplasia congenita (SEDc) is a rare autosomal dominant genetic disorder. Femoral head ossification delay and the proximal femur varus deformity i.e. coxa vara (CV) are the major features of SEDc. The accepted treatment is a valgus femoral osteotomy. The data on hip surgery in SEDc are scarce. In our database from 2006 to 2020, there were 6 SEDc patients. Four patients had surgery on 8 hips. Surgical treatment was indicated due to progressive CV deformity i.e. a decreasing neck-shaft angle (NSA), pain, limited hip abduction, and gait disturbances. In three patients, a novel surgical treatment was applied – a greater trochanter apo-physiodesis using “Eight-plate”. The patients were evaluated clinically and radiologically. The median age at first surgery was 6.3 years (range, 3.2 to 9.5 y) and the median follow-up period was 7 years (range, 5.6 to 14 y). The postoperative NSA was significantly improved with a mean increase of 13 degrees (P<0.001). Additional surgeries were needed in two patients. Overall, our results showed improved clinical and radiological parameters. The purpose of this study was to determine whether a method using an “Eight- plate” applied early to greater trochanter apophysis in SEDc patients with bilateral CV could reduce the need for more aggressive surgery in near future.