Relevance Application of 3D printing using the method of selective laser fusion for production of intervertebral cages is a topical trend of the spinal surgery. Purpose Assessment of the efficiency and safety of original interbody fusion implant application made of titanium alloy according to 3D printing technology with selective laser fusion. Materials and methods The original flattened bean-shaped cages, with an integral side part and an internal configuration in the shape of three-dimensional 1.5 × 1.8 mm porous lattice were tested . The products were made of Ti6Al4V powder using 3D printing technology with selective laser fusion. Post-processing of the products surface included abrasive blast cleaning using the SLA method and sterilization with ethylene oxide. Experiments on modeling interbody fusion with replacement of intervertebral discs with cages at levels L4 – L5 and L5 – L6 were performed in 8 mongrels. Additional primary stabilization of the lumbar spine was produced with an external fixator within 30 days after implantation. The total follow-up period lasted 180 days. Radiography, scanning electron microscopy, roentgenospectral and biochemical analysis methods were applied. Results X-ray examination demonstrated the contact between the frontal surfaces of the cages and the bone tissue of the vertebral bodies and the development of fusion in all experimental animals. Biochemical analysis did not reveal the signs of intoxication, indicating the danger of the products application. The microrelief of the implants was characterized by microroughness ranged from 1to 50 μm. In the surface layer of products, in addition to the elements of titanium, aluminum and vanadium, the carbon, oxygen, silicon, trace amounts of other organic and inorganic elements were found. Newly formed bone trabeculae were macroscopically and submicroscopically visualized in the sawcuts of bone blocks in the porous lattice of the internal part of the implants. Conclusions Experimental testing of porous implants made of titanium alloy using selective laser fusion has shown their effectiveness in obtaining interbody fusion and acceptable safety.

Федеральное государственное бюджетное учреждение «Российский научный центр "Восстановительная травматология и ортопедия" им. акад. Г.А. Илизарова» Министерства здравоохранения Российской Федерации, г. Курган

BACKGROUND:The use of intramedullary elastic nailing is a method of choice for prevention of complications in children with osteogenesis imperfecta. However, the morphology of the growing long bones in the conditions created was not investigated.AIM:The purpose of our experiment was to study the impact of elastic intramedullary nailing on the histostructure of long bones in their physiological growth.METHODS:Six mongrel dogs underwent intramedullary elastic transphyseal nailing of the intact tibia with two titanium wires. Six months after nailing, a light-optical microscopic and histomorphometric study of the operated and contralateral tibiae was performed.RESULTS:It was found that asymmetric lesion of the distal physis induces a decrease in the height of the distal epimetaphysis. Adaptive changes in the hyaline cartilage of both articular ends were revealed corresponding to the initial stage of chondropathy. Intramedullary nailing promotes an increase in the thickness of the compact bone and the volume of the trabecular bone.CONCLUSIONS:Elastic transphyseal nailing of the intact tibia has a shaping effect which is expressed by an increase in the volume of spongy and compact bone, adaptive changes in the hyaline cartilage. Asymmetric damage to growth zones should be avoided to prevent deformities.

Abstract BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication of joint arthroplasty. The identification of microorganisms in biofilm-related PJI is challenging yet significant stage of the treatment process. Medical microbiology methods, such as pure culture isolation, remain the gold standard. However, the error rate of classical methods may vary from 10% to as high as 42% due to the inability to detect bacteria growing within biofilms. Other methods of detection are being explored to improve the management of PJI. AIM: Accurate identification of PJI contributing microorganisms in a patient with acute postoperative PJI after total hip joint arthroplasty and systemic lupus erythematosus in anamnesis. METHODS: We used microbial culture methods followed by scanning electron microscopy (SEM). RESULTS: Perioperative an intraoperative cultural analysis of 8 different culture samples of tissue and prosthetic origin was insufficient for bacterial or fungal detection. Scanning electron microscopy revealed detailed biofilm visualisation on the surface of the prosthetic component. The biofilm exterior was composed of microbial clusters made of 10 or more cells with either pear- or bottle-shaped morphology, 3-6 mcm in length and 1.5-3 mcm in diameter. Rod-shaped microorganisms of 0.7-1 mcm length and up to 0.5 mcm in diameter were found adjacent to these clusters. CONCLUSION: Additional methods for PJI agents’ detection are time-and cost-effective in the case of the challenging diagnostics of biofilm-related PJI, particularly in immunocompromised patients. Using combined diagnostic approaches increases the accuracy of detection, justifies treatment strategies and improves clinical outcomes.

We propose an in vitro method for studying permeability of spinal cord dura mater for components of autological serum using an original device. Sixty native samples of the spinal cord dura mater obtained from 12 mongrel dogs were used for testing of the device. The coefficient of permeability variation (V) for blood serum substances did not exceed 5% in most cases excluding lactate (V=8.03%). Analysis of spinal cord dura mater permeability in vitro for various substances using the developed device provides reproducible results with acceptable variability (5-10%).