Preliminary investigation on the dissected methods of intraosseous vasculature and the clinical significances of intraosse-ous vascularity / 中华骨科杂志

ABSTRACT

Objective:The vasculature and canal were located using radiography after the fresh osseous specimens were decalcified, after which the anatomic investigation of intraosseous vasculature was conducted based on the orientation of the canals.Methods:To investigate the basic dissected methods for intraosseous vasculature and the related clinical significance. Methods The materials were obtained from seven fresh knee joint specimens from patients with amputation due to car accidents, nine fresh knee joint specimens from patients with amputation due to oncological radical surgery, and 44 knee joint specimens from 24 cadavers. Among them, 22 were males (55%) and 18 were females (45%), 28 were left knees (46.7%) and 32 were right knees (53.3%). 10 were aged from 16-90 years old (from 8 donors) and 50 were aged from 15-85 years old (from 32 donors). The tributaries of middle genicular vein which penetrate into the proximal tibial epiphysis and metaphysis via our previously discovered and denominated "foramen of tibial intercondylar eminence (FTIE)" were dissected as an example. After obtaining the fresh knee joint specimen, angiography was performed to observe the continuous extraosseous and intraosseous blood vessels. The first group of specimens with the removal of cortical bone was reserved in formalin solution at 4 °C for 7 d, sequentially immersed in Ethylene Diamine Tetraacetic Acid (EDTA), the decalcification agent, for 30 d with replacement for each two days. Based on the CT scanning and three-dimensional reconstruction, the orientation of bony canal which enclosed the vasculature was exposed to guide the anatomic incision. The exquisite dissection was achieved with the help of ophthalmological microsurgical instruments. The anatomical dissection were intuitively observed, compared with the angiographic images, and verified by histological examinations. The second group of samples was decalcified with strong acid as another strategy, and the comparison between different groups was conducted. To estimate the advantages and disadvantages of the two decalcification and dissection methods, and the distribution and universality of specific intraosseous vasculatures and canals, the methods can be utilized to dissect the diameter of the intraosseous vessels. Based on the anatomical study of intraosseous vasculature, the mechanisms including etiology, recurrence and spread of bone tumors and epiphyseal injuries were analyzed to improve the therapeutic regimen.Results:The intraosseous tributaries of middle genicular vein which penetrate into the tibial intercondylar eminence from the articular cavity were dissected, these vessels extended to the tibial metaphysis from epiphysis through the epiphyseal line or senescent physes. The diameter of the vessel entering the FTIE was 1.2 mm, and the intraosseous vessels divided into several tinier tributaries with the diameter of 0.3 mm to cross the epiphyseal line or closed physeal plate and differentiated into capillaries in the distal regions, therefore was difficult to dissect directly. The histological examinations confirmed the authenticity of intraosseous vessels. Compared with the samples decalcified with strong acid, the blood vessels were obviously dissolved, and only a few residual epithelial cells were observed under the light microscope. Based on the anatomical study of intraosseous vessels, the treatment protocols for some related bone tumors and epiphyseal injuries were modified and satisfactory results were achieved.Conclusion:The methods can realize the ideal direct dissection for the intraosseous blood vessels with the outer diameter greater than or equal to 0.3 mm.