MDCT Appearance of Human Xiphoid Process in 114 Patients Co-existent with Midline Congenital Sternal Foramina

Abstract

Introduction: Sternal Foramina (SF) are a congenital midline defect in sternum due to incomplete fusion of sternal ossification centres. The morphology of Xiphoid Process varies in patients with or without congenital midline sternal foramina. Aim: To evaluate various morphology of xiphoid process in patients with co-existent midline congenital SF by Multi-Detector Computed Tomography (MDCT). Materials and Methods: This retrospective study was carried out on 114 patients having midline congenital sternal foramina from March 2018 to April 2019. The MDCT scan images were evaluated in axial and reformatted planes. Morphometry of xiphoid process was evaluated. Data were presented in terms of percentage, mean and standard deviation and calculations were done using SPSS programs. Results: Morphometry of xiphoid process was evaluated in 114 patients having midline congenital SF. Type-I (oval shaped) xiphoid process was noted in 41 patients (36%), Type-II (pointed shaped) in 29 patients (25.4%) and Type-III (forked shaped) in 44 patients (38.6%). The shape of xiphoid process in sagittal plane noted as ventrally deviated in 78 patients (68.4%), reversed S-shaped (initial dorsal then ventral) in 25 patients (21.9%), dorsally deviated in 9 patients (7.9%), S-shaped (initial ventral then dorsal) in 1 patient (0.9%) and hook shaped in 1 patient (0.9%). Xiphoid process foramen detected in 20 patients (17.5%). Xiphoid process foramen pattern L (a larger foramen with diameter more than 5 mm) appeared in 11 patients (9.6%), pattern S (a foramen with diameter smaller than 5 mm) in 6 patients (5.3%) and pattern SS (two or more smaller sternal foramina) in 3 patients (2.6%). No statistical correlation was obtained between the various xiphoidal process morphology and various locations of congenital sternal body foramina in One way ANOVA test with p-value of 0.43. Conclusion: Variable morphological appearance of human xiphoid process was noted in association with congenital midline sternal foramina, however no gross morphological difference was observed in patients not having SF. But presence of xiphoidal foramina is more common in patients with SF. The anatomic appearances, degree of ossifications and xiphoido-sternal fusion were well evaluated with MDCT. The bifid, duplicated or trifurcated xiphoid process may be mistaken for fracture on imaging, hence detailed morphological knowledge of xiphoid helps in such situation.

Keywords

• ossification
• xiphoido-sternal fusion
• xiphoid fracture