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.