Abstract: Objective　To observe the morphology and blood supply pattern of the trapezium bone and trapezoid bone, and provide reasonable anatomical basis for the clinical application.　Methods　Twelve wrist specimens were perfused with a mixture of lead oxide and gelatin powder into the main arteries of the wrist. After the perfusion, the Micro-CT scan was performed. The scanning data were imported into the software of Mimics for three-dimensional reconstruction. The morphology of the trapezium bone and trapezoid bone was observed, the number and location of the nutrient foramens were recorded, and the anastomosis and course of the blood vessels in the bone were analyzed.　Results 　(1)The trapezium bone had a relatively constant number of nutrient foramen distributed on the three non-articular surfaces, which was (2.66±0.49) foramen on the radial side, (2.75±0.62) foramen on the dorsal side, and (2.33±0.65) foramen on the volar side, there were no statistical difference in the number of nutrient foramen among the three non-articular sides. The nourishing blood vessels branched out after penetrating into the bone and widely anastomosed with each other. About 70% of the blood supply in the bone came from the dorsal side, while 30% came from the volar and radial sides. (2) The trapezoid bone had a relatively constant number of nutrient foramen distributed on the two non-articular surfaces, (2.75±0.45) foramen on the dorsal side, and (2.42±0.51) foramen on the volar side, there were no statistical difference in the number of nutrient foramens between the two non-articular sides. The nourishing blood vessels branched out after penetrating into the bone, but its intraosseous blood vessel branch anastomosis was not as rich as that of the trapezium bone. About 70% of the blood supply in the bone came from the dorsal side, and 30% came from the volar side.　Conclusions　(1) The trapezium bone is rich in nourishing blood vessels from inside and outside the bone, which may be the reason why the incidence of the trapezium bone avascular necrosis is lower than other carpal bones. (2) The nourishing blood vessels outside the trapezoid bone are relatively abundant, but the intraosseous vascular anastomosis is not as rich as the large bone, this may be the main reason why the trapezoid bone are more prone to non-traumatic ischemic osteonecrosis than the trapezium bone.

Key words: Trapezium bone, 　Trapezoid bone, 　Avascular necrosis, 　Vascular perfusion, 　Mimics