Prevalence and orthopaedic relevance of the supranavicular bone: a systematic review with meta-analysis

Background: The supranavicular bone or os supranaviculare (OS) is a rare accessory ossicle of the foot located dorsally at the proximal navicular margin. This study aimed to estimate the pooled prevalence of the OS through a systematic review and meta-analysis and to discuss its anatomical and orthopaedic significance. Materials and methods : A systematic review and meta-analysis were conducted according to the PRISMA 2020 and Evidence-Based Anatomy Workgroup guidelines. Results: Twenty radiological studies comprising 23,816 lower limbs were included. The pooled prevalence of the OS was 0.79%, with significant heterogeneity across studies. CT-based studies reported a higher prevalence (2.88%) compared to radiographs (0.65%) (p < 0.0001). The ossicle was more frequently unilateral (1.01%) than bilateral (0.21%) (p = 0.0061), with no significant sex or side predilection. Conclusions: The OS is a rare anatomical variant with potential clinical and surgical relevance, particularly in the context of navicular pathology. Its presence should be considered in radiological assessment and preoperative planning, especially in athletes and patients with midfoot pain or stress injuries. Future anatomical and biomechanical investigations are needed to further elucidate its pathophysiological role.