Figure 2: A 5-year-old male syndromic AAD (chondrodysplasia punctuate); type 1 C1–C2 dislocation, subaxial cervical kyphosis due to C2/C3 vertebral body hypoplasia with reducible AAD. With the help of an animated model, we can access the CVJ development, particularly the development of lateral mass and lamina. In this child occipito-C4 long segment, fusion was performed for cervical instability