Morphological and Topographical Assessment of Nutrient Foramina of the Clavicle: A Study with Clinical Implications

Abstract

Background: The clavicle is a horizontally oriented bone that connects the upper limb with the axial skeleton and contributes substantially to the stability and mobility of the shoulder girdle. Its vascular supply is clinically important during fracture fixation, reconstructive procedures, and vascularized bone grafting. Nutrient foramina provide passage for nutrient arteries and demonstrate considerable variation in their number, position, and direction. The present study was undertaken to assess the morphological and topographical characteristics of nutrient foramina in human clavicles and to discuss their clinical importance. Materials and Methods: A total of 100 dried human clavicles obtained from Maharashtrian cadaveric material were examined, consisting of right and left clavicles. Specimens showing damage, deformity, or significant pathological changes were excluded. Each clavicle was examined for the number, surface position, regional location, and direction of the nutrient foramen. The distance of the nutrient foramen from the sternal end and the total length of the clavicle were measured. The foramen index was calculated using the Hughes formula: FI = (DS/TL) × 100. Results: At least one nutrient foramen was identified in every examined clavicle. A single nutrient foramen was reported in 70% of specimens, two foramina in 24%, and three foramina in 6%. The posterior surface was the most frequent site, accounting for 55.88% of observed foramina, followed by the inferior surface at 41.17% and the superior surface at 2.94%. The middle one-third was the most common regional location, accounting for 70.58%, followed by the lateral one-third at 19.11% and medial one-third at 10.29%. The mean distance of the nutrient foramen from the sternal end was 69.63 mm, while the mean clavicular length was 133.26 mm. The calculated foramen index was 52.25. The nutrient canals were directed toward the acromial end. Conclusion: The nutrient foramina of the clavicle show considerable variation in number and location, although a predominance of a single foramen, posterior-surface location, and middle-third distribution was observed. Recognition of these anatomical patterns is important during clavicular surgery, internal fixation, and procedures involving vascularized bone grafts because preservation of the nutrient blood supply may contribute to satisfactory bone healing.