Carbon-carbon composite nail for intramedullary osteosynthesis in rats with experimental osteoporosis

Background. In Ukraine, there has recently been an increase in the number of limb bone fractures among the population, in particular, due to increase in the number of elderly people, which is associated with the development of age-related osteoporosis and fragility of bones. Therefore, the use of artificial implants in traumatology is becoming increasingly important. The search for new bioinert and biodegradable materials, that are capable of providing rapid fracture consolidation and do not require repeated surgical intervention, continues. Objective. To elaborate a model for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis. Methods. The work investigated the lower limbs of 6 groups of Wistar rats. The first part of the study involved 4 groups of rats with modeled tibial fracture with subsequent osteosynthesis in norm and with experimental osteoporosis. The second part of the research included two groups of laboratory rats with modeled femur fracture. In both parts we used metal injection needle, as well as carbon-carbon composite nail for osteosynthesis. Results. All animals underwent surgery well, stepped on the injured limb. X-ray examination after the osteosynthesis demonstrated satisfactory reposition of the fragments. One month after modeled fracture in rats with experimental osteoporosis a violation of the normal consolidation of the fracture was observed, especially in the group where carbon-carbon composite nails were used for osteosynthesis. Further, until the 180th day after the surgery there were no peculiarities, function of the limbs was restored, mainly without expressed angular deformities. Conclusion. The above mentioned model was successfully elaborated for the research of using carbon-carbon composite nail for intramedullary osteosynthesis in laboratory rats with fractures of femur and tibia in norm and with experimental osteoporosis.

Miniinvasive intramedullary osteosynthesis of clavicular fractures in middle one third with shifted fragments using elastic titanic compressing rod

Objective. To estimate the results of operative treatment of clavicular fractures in middle one third with fragments shifted, using the closed method with application of intramedullary elastic titanic compressing rod. Materials and methods. In the Department of Orthopedics and Traumatology of Kyiv Municipal Clinical Hospital No. 6 («Medgorodok») in 38 patients ageing 18 - 67 yrs with the closed clavicular fractures in middle one third with shifted fragments the closed intramedullary osteosynthesis, using elastic titanic compressing rod, was performed. Methods of the patients examination, indication s for operative treatment, its technique, late results of the operation were studied. Results. While estimating late results in 12 mo postoperatively in accordance to Constant Score (estimation of the brachial joint function) there were (97.1 ± 3.5) points of 100 possible points noted at average. In all the patients the movements in brachial joint were free and painless, they served themselves completely while doing solemn round of industry, coming back to their ordinary profession activity and sport. Conclusion. Intramedullary osteosynthesis of clavicular fractures in middle one third, using elastic titanic compressing rod as method of operative treatment, may guarantee satisfactory late results.

Violation of consolidation of the femur after untimely dynamization of the intramedullary blocking rod

Violation of femoral fracture consolidation after blocking intra­medullary osteosynthesis is a fairly common pathology, and requires the attention of physicians due to its prevalence. There are several reasons for this complication: it is the instabi­lity in the system «bone-implant», and the untimely dynamization of the locking nail. Methods. This article presents a case of fracture violated consolidation after blocking intramedullary osteosynthesis caused a nonunion due to nail failure. Results. Patient was injured on 29.12.2018, as a result of a traffic accident. 01.15.2019, the surgery was performed: closed reduction, blocking intramedullary osteosynthesis of the fracture of the middle shaft of the right thigh, static fixation of the nail. Next visit to the clinic was on 02.01.2020, because of pain in the middle third of the thigh, problems with axial weight-bearing on the right leg, limitation of the flexion in the right knee joint. Control radiographs demonstrated no signs of consolidation of the femoral shaft fracture, and migration of the distal locking screw. 08.01.2020 revision surgical treatment was performed. Given the presence of 5 mutually perpendicular holes in the distal part of the nail, two of them were locked in the anterio-posterior view by the free hand method, the migrated screw in the distal part of the nail was replaced, and the nail was dynamized in the proximal part taking into account its design features. Conclusions. To normalize the consolidation processes in patients with nonunion femoral fractures, bone physiology and the positive effect of autocompression should be considered. The described case demonstrates the necessity for timely dynamization of the blocking nail, which confirms our own observations and literature data. Despite the fact that the dynamization of the nail was performed 1 year after blocking intramedullary osteosynthesis, fracture consolidation occurred 5 months after its implementation. Key words. Femoral fracture, blocked intramedullary osteosynthesis, disorders consolidation, dynamization of the construction.

Experimental Modeling of Combined and Sequential Use of Transosseous and Intramedullary Blocking Osteosynthesis

Background. The introduction of the combined and sequential application of transosseous and intramedullary blocked osteosynthesis in limb lengthening requires an experimental study of the features of distraction regenerate. For small animals (in particular rabbits), special models are required.Aims. To develop experimental models of sequential and combined use of transosseous and intramedullary osteosynthesis in limb lengthening and substantiate their effectiveness.Materials and methods. A comparative study was carried out on 30 rabbits of the Soviet Chinchilla breed. Experimental models of sequential (EM-1) and combined (EM-2) application of transosseous and intramedullary osteosynthesis with preservation of the apparatus during the fixation period to simulate blockage were studied in the main groups. For comparison, sequential (comparison model 1 – CM-1) and combined (comparison model 2 – CM-2) use of transosseous and intramedullary osteosynthesis with dismantling of the apparatus at the end of distraction were modeled. The control was a regenerate formed according to the classical Ilizarov method. Radiographs were performed in dynamics, CT and morphological studies – at the end of the fixation period.Results. It was noted that regenerates of the same type in structure were formed in the EM-1 and CM-1 groups, as in the EM-2 and CM-2 groups. With successive methods, the spindle-shaped form of the regenerate prevailed, the formation of a pronounced periosteal component was noted. Powerful cortical plates, according to morphological studies, are formed from the periosteal and intermediate zones. With combined techniques, the cortical plates are formed thinner and predominantly from the periosteal component, the shape of the regenerate is closer to fusiform. In the comparison groups, the total time of surgical interventions was 25–50 % longer, in 50 % of cases there was a loss of length or deformation of the regenerate.Conclusions. The developed models of sequential and combined use of transosseous and intramedullary osteosynthesis for limb lengthening with preservation of fixation with an apparatus to simulate blocking have proven to be reliable in terms of fixation and easy to use on small laboratory animals..

Choice of a Method for Blocked Intramedullary Osteosynthesis in Tibial Fractures in the Context of Topographic-Anatomical Research

Blocked intramedullary osteosynthesis has become a "gold standard" for the treatment of patients with diaphyseal fractures of the tibia. However, there is still debate about the importance and necessity of reaming the bone marrow cavity when performing intramedullary osteosynthesis.The aim is to study the individual features of the structure of the medullary cavity of the tibia in relation to intramedullary osteosynthesis, as well as to evaluate the effect of blocked intramedullary osteosynthesis with preliminary reaming and without reaming of the bone marrow cavity on the vascular supply of the tibia.Material and methods. Using morphometric and radiological methods, an experimental topographical and anatomical study was carried out on 26 dry preparations and histotopograms-plates of tibial bone cuts, as well as on 10 lower limbs of corpses with X-ray contrast injection of arterial vessels. Statistical analysis was performed using the Student's parametric test and the nonparametric MannWhitney test.Results. Particular attention was paid to the detailed study of the main parameters of the tibial bone marrow cavity that are important for the technology of blocked intramedullary osteosynthesis (size, shape and curves of the bone marrow cavity, architectonics of its narrow part, density and distribution of spongy matter in it, topography of the a. nutricia tibialis channel and distribution of its branches). To assess the invasiveness of osteosynthesis on 10 anatomical objects with preliminary injection of vessels of the lower extremity with X-ray contrast mass, blocked intramedullary osteosynthesis of the tibia with and without reaming of the bone marrow cavity was modeled.Conclusion. It was concluded that any variant of intramedullary rod insertion is accompanied by damage to a. nutricia tibialis in a narrow part of the bone marrow cavity, and reaming of the bone marrow cavity has certain advantages in view of the pronounced individual differences in the structure of the tibia.

Controversial technologies in intramedullary osteosynthesis of rats femur fractures

The aim: to conduct a comparative study of osteoreparative regeneration, namely in the periosteal and intermediate areas of the cortex, during intramedullary osteosynthesis of the femur of rats with and without reaming of the bone marrow canal. Materials and methods. The work is based on the results of an experimental study conducted on 56 white mature laboratory rats, which simulated diaphyseal fracture of the femur and performed stable nail osteosynthesis with reaming of the bone marrow canal in the first series and without reaming in the second series of the experiment. Histological examination of the specimens was performed on the 7th, 14th, 28th and 90th day after surgery. Results. The procedure of reaming the bone marrow canal reduces the potential reparative capacity of bone tissue in the endosteal area and leads to “distorted” activation of the process of the cortex restructuring. There is a significant activation of osteoclastic resorption. Conclusions. Bone fusion is more active with the use of intramedullary fixator without reaming of the bone marrow canal, because its reaming reduces the manifestations of reparative potentials in the endosteal region and leads to excessive activation of the resorptive process of restructuring the cortex of both endosteal and central part

auto-dynamic intramedullary osteosynthesis for femur fractures and consequences of injuries

The assessment of clinical testing results of the new intramedullary rod which design features neutralize the disadvantages of conventional blocking devices.

The First Experience of Dynamic Intramedullary Osteosynthesis of Diaphyseal Fractures of the Tibia Using Implants Based on Magnesium Alloy

Summary. The efficiency of using the dynamic blocking intramedullary osteosynthesis (BIOS) technique for tibial fractures with the use of biodegradable implants based on the MS-10 magnesium alloy was determined. Objective: to approve the technique and to study the effectiveness of dynamic intramedullary osteosynthesis of diaphyseal fractures of the tibia using locking screws made of the biodegradable magnesium alloy MS-10. Materials and Methods. The study was carried out in the Department of Traumatology of the Municipal Non-Profit Enterprise “City Hospital of Emergency and Ambulance” of Zaporizhzhia City Council in Zaporizhzhia on 15 patients with diaphyseal fractures of the tibia, who underwent BIOS. Cannulated intramedullary titanium rods were used as a fixator. In the proximal section, a screw made of titanium alloy was introduced into a dynamic hole; a screw made of a biodegradable magnesium alloy MC-10 was inserted into a static hole. In the postoperative period, the patients underwent a course of complex rehabilitation measures. X-ray control was performed on day 1, at week 4, week 8, and week 16 after the surgery. Results. After the start of the dosed load on the injured limb, a fracture of the locking screw made of MC-10 alloy was radiographically recorded in all patients. The dynamic screw moves in the dynamic hole and the fracture is dynamized. The formation of callus in the fracture zone was unremarkable and took an average physiological time. The quality and structure of callus did not show any pathological features. Four months after the surgery, all patients were socially adapted and did not use additional support when moving. Conclusions. Based on the data obtained, it is possible to draw a conclusion about the possibility and advisability of using biodegradable implants made of magnesium alloy MS-10 in a dynamic BIOS of long bones of the human skeleton.

Experience In Surgical Treatment Of Diaphysical Fractures Of The Shin Bones

The results of blocked intramedullary osteosynthesis (BIOS) in 50 patients with fractures of the distal and diaphysis of the tibia are presented. Blocked intramedullary osteosynthesis is a reliable and predictable method for the treatment of diaphyseal fractures of the tibia, which allows the restoration of limb function in the shortest possible time in most patients.