Anatomy of the diaphyseal nutrient foramen in the long bones of the pectoral limb of German Shepherds

This study investigated the anatomy of the nutrient foramen (NF) in German Shepherds by recording the number, site, position, and direction of penetration of the nutrient canal (NC) in the humerus, radius, and ulna of 50 individuals. The site index of the nutrient foramen (SI) was calculated as the ratio of the length to the NF site from the proximal end to the greatest length of the bone. The NF diameter was measured using different sized needles. Most humeri had only one NF on the caudal surface, particularly on the lateral supracondylar crest, or distal cranial surface. All radii had one NF, usually on the caudal surface, while most ulnae had one NF located on either the cranial or lateral surfaces. The SI and NF diameters were 58.0∼59.5% and 0.73∼0.78 mm in the humerus, 30.4∼30.9% and 0.74∼0.76 mm in the radius, and 29.3∼29.8% and 0.67∼0.68 mm in the ulna, respectively. With the exception of the relatively proximal NF of the radius, the direction of penetration followed Berard's rule. This study provides novel information on the location and diameter of the NF and direction of the NC in the long bones of the pectoral limb of German Shepherds.