Automatic Distraction Research Articles

Analysis of the use of classical compression–distraction devices and the latest device for continuous distraction

BACKGROUND: The device used in bone tissue fragment mechanical displacement by expanding the piston between rigidly fixed device legs on the bone fragments is known in classical compression–distraction osteogenesis. In such cases, the control of the displacement is partly left to the patient, since the screw turning must be performed in four sessions per day, and the doctor does not constantly have the opportunity to do it personally, which can lead to uncontrollable results of bone regeneration. To fully control the patient's treatment during distraction, a device that operates continuously and autonomously is required.
 AIM: Creation and experimental testing of an automatic distraction device for continuous distraction followed by a study of the obtained bone regenerates and its implementation in practical maxillofacial surgery.
 MATERIALS AND METHODS: To fully control the patient’s treatment during the distraction, we developed an unparalleled distraction device based on the principle of continuous bone fragment separation, with a motor in which the piston is activated by an electrochemical reaction. The device performs distraction continuously, around the clock, and autonomously under the control and monitoring of the software and the possibility of remote access. This study included analysis of statistical data on patient treatment in the Russian University of Medicine Department of Pediatric Maxillofacial Surgery Clinic between 2010 and 2021, development and bench testing of devices and electronics, clinical trials of models of devices for continuous distraction at various rates (1, 2, and 3 mm/day) on experimental animals (dogs), X-ray control at the stages of testing, research and analysis of the morphological structure of the resulting bone regenerates, creation of clinical guidelines for the use of a continuous distraction day device, and identification of its advantages compared with the classic fractional compression–distraction device.
 RESULTS: Statistical data analysis revealed that 362 patients were treated with distraction devices. This is a relatively high percentage in relation to all patients in the clinic. Studies of the morphological structure of regenerates obtained by continuous distraction with our latest device revealed a higher rate and control of regenerates, good quality characteristics, and histomorphological maturity, most pronounced in regenerates obtained by continuous distraction at a rate of 2 mm/day.
 CONCLUSION: The need for treatment with distraction osteogenesis in the department’s clinic is rather high; hence, this process should be controlled to improve treatment quality and speed. Our automatic distraction device designed for continuous distraction may be implemented and applied in practical medicine at an appropriate rate of 2 mm/day.

Viewing a flower image provides automatic recovery effects after psychological stress

Multiple previous studies have reported that viewing natural scenery supports recovery from psychological stress. Viewing flowers is thus predicted to provide a recovery effect similar to that of viewing natural scenery. It remains unclear, however, how effectively viewing flowers promotes recovery and how the practice affects the brain. Using psychological, physiological, and neuroscientific techniques, we investigated the process through which viewing flowers regulates emotion. We found that passive viewing of a typical flower image downregulated negative emotions and decreased both elevated blood pressure and cortisol levels, which are two signs of stress-induced elevation, in response to an acute visual stressor (negative images). Using functional magnetic resonance imaging (fMRI), we examined brain-activation patterns relevant to emotion regulation with automatic distraction upon viewing the typical flower image. We demonstrated that activation of the right amygdala–hippocampus region was decreased during viewing of this image in comparison to viewing a flower-mosaic or a visual fixation point after an acute visual stressor. Our results suggest that viewing a flower may induce automatic distraction from a stressor and lead to a reduction in amygdala–hippocampus activation and negative emotion, thereby downregulating physiological responses.

Causes of peroneal neuropathy associated with orthopaedic leg lengthening in different canine models

Peroneal neuropathy is one of the complications of orthopaedic leg lengthening. Methods of treatment include slowing of distraction and decompression both of which may lead to additional complications. The purpose of this study was to analyse the changes in histologic peroneal nerve structure during experimental orthopaedic lengthening using various modes of manual or automatic distraction. The obtained data provide the basis for better understanding of peroneal neuropathy pathogenesis and refinement of prophylaxis and preventive treatment protocols. Four experimental models of canine leg lengthening using the Ilizarov fixator were studied: 1 (n = 10)—manual distraction—1 mm/day divided into four increments; 2 (n = 12)—automatic distraction—1 mm/day in 60 increments, 3 (n = 9) and 4 (n = 9)—increased rate of high frequency automatic distraction: 3 mm/day in 120 and 180 increments, respectively. In peroneal nerves semi-thin sections cross-sectional fascicular areas, content of adipocytes in epineurium, endoneurial vascularisation, morphometric parameters of nerve fibres were assessed by computerised analysis at the end of distraction and of consolidation periods and 30 days after fixator removal. In Groups 1–2 massive nerve fibre degeneration along with epineural vessels obliteration was revealed in two cases from 22, whereas in Groups 3–4 there were 10 from 18 (p < 0.01). Injuries of perineurium and endoneurial vessels were noted in Group 3, and long-lasting thinning of nerve fascicles in Group 4. The decrease in epineurial fat tissue was revealed in all groups, more drastic in 3. Modifications and injuries of nerve sheaths and blood vessels depending on distraction rate and frequency contribute to peroneal neuropathy. Its mechanical, circulatory and metabolic causes are discussed.

Histomorphometric analysis of knee synovial membrane in dogs undergoing leg lengthening by classic Ilizarov method and rapid automatic distraction

This pilot study aimed to test the theory that different lengthening methods affect the microscopic structure of knee joint synovium in diverse ways. This was a descriptive and analytical cross-sectional study of synovium carried out in two experimental models of canine leg lengthening using the Ilizarov fixator. Group 1 (n = 6) used manual gradual distraction most commonly used in clinical practice at one millimetre/day divided into four equal increments, 0.25 mm at each increment. Group 2 (n = 7) used an increased rate of automatic distraction at three millimetres/day divided in 120 increments, 0.025 mm at each increment. At the end of distraction and after fixator removal, the animals were euthanised. Control was via intact dogs. The thickness of the synovial lining layer, number of synovial cell rows, and numerical density of subsynovial microvessels were assessed in digital images for semiautomated computerised analysis of semi-thin sections stained with toluidine blue and methylene blue-basic fuchsin. Comparison of synovitis manifestation was made with grading scale. The vascular and nerve changes in the subsynovial layer were also compared. Group 1 developed marked synovitis, synovium hypervascularisation, degeneration of the nerve fibres in subsynovial nerves with the tendency to regeneration. Group 2 had moderate to mild degree of synovitis with progressive degenerative changes in subsynovial vessels and nerves. Both methods used are unfavourable for the state of the joint synovium, but modify it in different ways.

An Implantable Battery System for a Continuous Automatic Distraction Device for Mandibular Distraction Osteogenesis

Distraction osteogenesis is a method of generating new bone formation by the gradual application of tensile stress across an osteotomy site (a complete cut through the bone). Internal or intraoral distraction devices have become the most common clinical apparatus in craniofacial distraction osteogenesis, although actuating the distraction devices relies upon manual length adjustment under patients’ compliance, introducing inconvenience and potential error in the procedure. To realize a fully implantable automatic distraction device, we propose a device design comprising a continuous miniature motor-driven distractor with a controller and an on-board lithium-ion battery. A benchtop prototype was fabricated to demonstrate the device’s structural design capable of transmitting sufficient loads with sufficient strain accuracy; it is capable of using a battery selection algorithm to determine an appropriate electrochemistry, temperature, sealability, and form factor and a control algorithm and a testing protocol with a laboratory-fabricated control circuit. This new distraction osteogenesis device enables completely automated and continuous distraction by the application of a low strain magnitude with multiple steps potentially leading to enhanced osteogenic activity.

Poster 183: Development of an Implantable Continuous Automatic Distraction Device

Poster 183: Development of an Implantable Continuous Automatic Distraction Device

Implantable Battery Design for a Continuous Automatic Distraction Device

not Available.

Mandibular elongation by automatic distraction osteogenesis: The first application in humans

We report the case of a 65-year-old man who was the first person to have the right ramus of his mandible lengthened by 20 mm by automatic continuous distraction osteogenesis. The device consists of two units: a component that is implanted into the bone, and an external component that is distant from the surgical site and mounted on a battery-driven portable syringe driver or infusion pump. A non-compressible drive cable connects the two.

Segmental mandibular reconstruction by microincremental automaticdistraction osteogenesis: an animal study

We investigated the reconstruction of a surgically created critical size mandibular defect in sheep using a newly developed automatic distraction device. The device has an implantable component, which is fixed to the mandible to allow the transfer of the transport disc across the created defect, and an external component which is mounted on the activation pump and secured away from the site of bone distraction. Compression of the bellows in the external component causes fluid to be forced through the connecting tube into the distraction component. Distraction at a rate of 1 mm over 24 h was achived in six sheep. New bone generated at the site of the created defects both anterior (compression side) and posterior (tension side) to the transport disc and had similar radiodensity to the adjacent mandibular bone eight weeks after the completion of distraction.