Multiple Ossification Centers of the Pubic Bone as a Supportive Radiographic Feature for COL2A1-Related Congenital Spondyloepiphyseal Dysplasia.

Background/Objectives: During analysis of patients with genetically confirmed COL2A1-related skeletal dysplasias, we observed an unusual ossification pattern of the superior pubic ramus characterized by multiple ossification centers-a phenomenon not previously reported in this context. The study aimed to determine the consistency and frequency of multiple ossification centers of the superior pubic ramus in patients with COL2A1-related skeletal dysplasias. Methods: We retrospectively analyzed pelvic radiographs from 135 patients with genetically confirmed pathogenic COL2A1 variants. Patients were classified into four clinical subgroups: SEDC, MED, Kniest dysplasia, and Stickler syndrome. Results: Multiple ossification centers were identified in 20 (15.5%) of the included patients, all of whom had the SEDC phenotype. The sensitivity of this radiographic sign for SEDC was 36.36%, with high specificity (99.07%) and accuracy (96.5%) compared with other COL2A1-related phenotypes and historical general population data. However, these findings require cautious interpretation given the limitations of historical control data. Conclusions: We identified an uncommon atypical ossification pattern of the superior pubic ramus that may serve as a supportive radiographic feature when interpreted in conjunction with clinical and genetic findings.