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[Abstract] Objective The purpose of this study is to construct a high-resolution model focusing on the vascular pattern of the scaphoid by using micro CT and to provide anatomical reference for the daily clinical use. Methods The lead-based contrast was perfused from the brachial artery and then the scaphoid bone was harvested. 3D models of the scaphoid bones were constructed by using micro CT to show how arteries distributed in and on the bones. Results The arteries on the surface stretched from the distal radius covered with scaphoid fossa to the radial side of the waist and then head back to the distal ulna along the dorsoradial ridge, formed like a letter “Ⅴ”. The arteries gathered at the inflection point of the letter “Ⅴ” and the dorsal region. The tubercle region was anastomosed extensively with 3 to 5 major intraosseous vessels originated from the extraosseous vessels covering the waist and the tubercle. There are only 1 to 2 major intraosseous vessels entering the bone via a long route from the ulnar side. The vessels running in the scapholunate ligament didn’t spilt into any intraosseous branches. Conclusion The superficial vascularity formes a “Ⅴ”-like pattern. The inflection point of the letter “Ⅴ” and the dorsal region display a dense vascularization and these vessels contributed a lot to the intraosseous vascularity.
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OBJECTIVE@#To obtain three-dimensional intraosseous artery of the hamate and to provide the vascular anatomy basis of hamate fracture fixation.@*METHODS@#PbO (lead monoxide, Sinopharm Chemical Reagent Beijing Co. Ltd) was ground into particles less than 40 μm and suspended in turpentine oil (Chemical Reagent Beijing Co. Ltd) at ratios of 1 g : 1.5 mL, 1 g : 1 mL and 1 g : 0.5 mL. Three specimens were investigated. Brachial arteries were cannulated and perfused with lead-based contrast agent. Hamates were harvested and scanned using micro-computed tomography (microCT). The acquisition protocols were as follows: CT scan setup: total rotation [Degrees], 360; rotation steps, 360; X-ray detector setup: transaxial, 2048; axial, 2048; exposure time, 1 500 ms, Binning, 1; system magnification: high-med. X-ray tube setup: 80 kV, 500 mA current. The down-sampling factor used in the reconstruction was 2. The effective voxel size of the final image was 27.30 μm. The three-dimensional model of the hamate was generated and the distribution and pattern of vessels were evaluated.@*RESULTS@#There were abundant extraosseous vessels around the hamate. They were mainly running in the tendons and ligaments around the hamate. Four vascular zones were identified on the hamate surface. They were on the palmar platform of the hamate body, on the dorsal side, on the ulnar side and on the tip of hamulus, namely. There were anastomoses among 4 vascular zones. We did not observe any vessels penetrating through the articular cartilage. The extraosseous vessels of the vascular zones gave a number of intraosseous branches into the hamate. The hamate body received intraosseous blood supply from the dorsal, palmar and ulnar while the hamulus from the palmar, ulnar and hamulus tip. There were some intraosseous branches anastomosing with each other.@*CONCLUSION@#The extraosseous and intraosseous vessels of the hamate were more than what used to be considered. The hamate body and hamulus received blood supply from multiple directions and arteries anastomosed extensively both outside and inside the hamate, making it possible that the intraosseous perfusion survived after fracture. It is likely that the nonunion after the hamate fracture is not caused by the vascular damage but the malalignment of the fragments.