Distraction Rate Research Articles

Success of Bone Ossification After Posterior Vault Distraction Osteogenesis in Patients With Craniosynostosis

Background: Posterior vault distraction osteogenesis (PVDO) is an effective treatment for multisuture and syndromic craniosynostosis. It remains unclear how well the calvarium ossifies after PVDO, especially in older patients when they have plateaued in their cranial growth phase. The purpose of this study is to report outcomes associated with PVDO across a wide range of ages at our institution. Methods: Operative details, distraction parameters, complications, and details of cranioplasty, if applicable, were obtained for all patients who underwent PVDO between March 2016 and July 2022. The surface areas of distraction sites and residual cranial defects were measured from computed tomography scans after a consolidation phase, and the percentages of the distraction regions with ossification were subsequently calculated. Results: Fifteen patients underwent PVDO at a mean age of 5.1 years (0.5–18.7 y). The mean percentage of ossification among all patients was 80.4% (59.1%–95.3%). The degree of ossification was not significantly associated with age at the time of surgery at the univariate level (Pearson-r=−0.15, P=0.573). Three patients (20.0%) required titanium mesh cranioplasty for definitive reconstruction, which was significantly more likely in patients who were >4 years old at the time of PVDO (P=0.04). Conclusions: Complete ossification of the distracted area of the cranium is unlikely after PVDO. Ossification appears less robust with increasing age, although not statistically significant in our study population, likely due to the limited sample size. Future studies should assess the role of age, latency period, and distraction rate in minimizing residual defects.

Surgical correction of posttraumatic triphalangeal joint flexion contractures of the fingers (systematic literature review)

Introduction Triphalangeal joint flexion contracture of the fingers is a common and challeging posttraumatic hand condition. The goal of surgical treatment is to correct finger deformity and increase interphalangeal range of motion.The objective was to systematize data on the causes of post-traumatic triphalangeal joint flexion contracture of the fingers and methods of surgical correction.Material and methods The original literature search was conducted on key resources including Scientific Electronic Library (www.elibrary.ru), the National Library of Medicine (www.pubmed.org), ScienceDirect, Google Scholar, Ovid databases according to PRISMA recommendations. Literature searches included both Russian and English studies, with one or more cases of post-traumatic triphalangeal joint flexion contracture of the fingers with the deformity surgically corrected. Cases of non-traumatic flexion contractures were excluded. Etiological factors of flexion contractures, heterogeneity of definitions and methods for recording the range of motion in the joint, anatomical features, surgical correction of flexion contractures and postoperative complications were reviewed.Results Common causes of flexion contractures included burns (32.3 %), dislocations and fracturedislocations of the finger joints (23.5 %). The median postoperative follow-up period was 13.5 months after surgical treatment. Surgical correction was produced with external fixation device (EFD) in 40 % of cases, open procedures performed in 50 % and a combined technique employed in one case (10 %). Based on calculations of the odds ratios of postoperative complications, a weak positive linear relationship was revealed between EFD and pain syndrome, and a weak negative linear relationship was observed between the open procedure and pain.Discussion There is heterogeneity of approaches regarding methods for correcting flexion contractures, surgical approaches, techniques for mobilizing joints and releasing the anatomical structures of the finger with open procedures, the distraction rate with EFD, methods for repair of soft tissue defects following the treatment of flexion contractures of interphalangeal joint of a finger.Conclusion Open procedures are commonly used for precise elimination of all components of flexion contracture of the joint and repair of soft tissue defects of the finger. A weak positive linear relationship was revealed between EF and pain syndrome. There was no significant correlation between open techniques and complications. There were no correlations between the treatment method and the contracture type; there are no treatment regimens for patients with this pathology.

Artificial deformity creation in treatment of soft tissue wounds and lower leg bones defect: a case report

Background. The problem of treating wounded patients with defects of soft tissues and bones of the extremities continues to be relevant. One of the ways to close soft tissue defects, especially in case of bone tissue loss, after open fractures of the extremities is acute shortening and creation of artificial angular deformity of the segment. The aim of the study — to demonstrate the possibilities of acute shortening and angulation of the segment as a technique to replace soft tissue and bone defects in treatment of a patient with a gunshot wound to the lower leg. Case description. A 30-year-old wounded man was admitted to the clinic with an extensive defect in soft tissues and bones of the lower leg in the middle third. To reduce the wound size, acute shortening and angulation of the lower leg was performed. The intentional angular deformation was 24º, shortening — up to 8 cm. The residual soft tissue wound defect was closed with local tissues and split skin autograft. The tibia was fixed by the Ilizarov hinge-distraction apparatus with following gradual correction of the angular deformity. After that, one performed osteotomy of the tibia in order to eliminate shortening with the Ilizarov method (the distraction rate of 1 mm per day). After restoring the length of the lower leg, in order to replace the defect along the anterior surface of the tibia, a marginal “flake” was formed from a displaced fragment. At a follow-up examination, in 18 months after the injury the patient walks with full weight bearing on the injured limb without any additional means of support, continues to perform military service duties in accordance with his position. Conclusions. The presented clinical case demonstrates that acute shortening of a limb segment with creation of artificial angular deformity is an effective method for temporary closure of a gunshot defect of soft tissues. The technique allowed closing critical soft tissue defect of the lower leg and restoring the anatomy (length) of the segment. Consequently, one was able to achieve satisfactory treatment results and restore the functions of an injured limb. Besides, acute temporary shortening technique eliminated the need to perform technically sophisticated and lengthy microsurgical reconstructions, which are associated with a flap replacement for closure of soft tissue defects in a shotgun fracture area.

Közúti közlekedési balesetben megsérült gyalogosok számának csökkentési lehetőségei

Összefoglalás. A közlekedési balesetekben sérült személyek, valamint a baleset miatti anyagi károk jelentős mértékű társadalmi-gazdasági veszteségértéket képviselnek. Kutatásommal célom a közlekedés biztonságosabbá tételéhez szükséges kulcsterületek feltárása és a lehetséges potenciális beavatkozási területek meghatározása volt. Munkám során a 2016–2020 közötti közlekedési balesetek adatait elemeztem leíró statisztikai módszerrel. Megállapítottam, hogy a leginkább kritikus pont a gyalogosok közlekedése. Azokban a balesetekben, ahol volt gyalogos sérült, a balesetek két okcsoportja dominál: gyalogosok hibája (34,3%), valamint a járművezetők gyalogosok részére történő elsőbbségadásának elmaradása (38,1%). Az eredmények lehetőséget adnak a további célirányos vizsgálatokra, valamint a hatékony beavatkozásokra. Summary. Transport is an essential part of everybody lives. The aim of transport users is to make their journeys without accidents in the shortest possible time, while optimising their individual resources and inputs. The number of people injured in road traffic accidents with personal injury and the material damage caused by a significant socio-economic loss. By preventing accidents, it is clear that the costs and resources spent on road accidents can be reduced. Therefore, I started my research by determining the share of road user groups in the number of accidents, the number of people injured and the amount of economic loss value associated with accidents. I analysed road accidents between 2016 and 2020. By the accident analysis, I found that among vulnerable road users, the proportion of pedestrians and cyclists injured was extremely high. Injuries in these two transport modes accounted for more than half of the injuries in cars. By calculating the loss value, I found that the damage to the national economy caused by pedestrian injuries was significant. In my research, by analysing the causes of accidents, I found that in accidents where there was a pedestrian injured, two groups of causes dominate: pedestrian error (34.3%) and drivers not giving priority to pedestrians (38.1%). Examining the accident data, it was evident that the number of pedestrian accidents due to pedestrian error is very high, so I continued my research in the area of other activities of pedestrians while walking. I measured pedestrians in 10 locations in Budapest. During the measurements, I recorded and analysed data of 11536 persons. The average rate of distraction was 54.3%, which means that one in two pedestrians is doing some other activity while walking. The most frequent activity was talking to another pedestrian (29.8%), but phone use (15.7%) and head/earphone use (13.5%) were also very significant. My research results so far show that if we want to improve pedestrian safety, we need to reduce accidents caused by pedestrians’ own fault and increase drivers’ willingness to give priority to pedestrians. My research plans also include investigating ways to reduce pedestrian errors, increasing pedestrian awareness and examining pedestrian-driver interactions in more depth. I already have results in this area, but my aim is to identify target areas (including human, infrastructure, vehicle field) for my research that can be implemented in practice, thus helping to improve pedestrian safety and road safety.

Histomorphologic, Biomechanical, and Functional Analysis in Mandibular Osteogenesis Induced by External Distraction

The induced bone generation procedure (osteogenic distraction [OD]) is frequently used in cases of jaw deformities in patients with, hemifacial microsomia, mandibular hypoplasia, and so on. This study was undertaken to provide criteria to perform this procedure. The authors evaluated the effects of various parameters using OD to determine the optimal variables. Sixty distractors were placed in 30 canine subjects who then underwent OD after appropriate osteotomy. The procedures were performed during varying latency periods, distraction periods, distraction rate distance, and the consolidation period. Bone biopsies and radiographic studies were performed at 0, 7, 14, 21, 45, and 55 days after the distraction process. The observed changes and the most efficient mandibular OD parameters are reported.

A novel approach to characterize the correction path features for the tibia deformity correction.

Preoperative correction path planning is an important preparation for obtaining the desired correction. However, a convenient and effective model has not been proposed to characterize the correction path features, especially how to visualize the growth process of the bone cross-section has not been investigated. In this paper, a new characterization approach of the correction path features and corresponding evaluation indexes are proposed for the tibia deformity correction. We represent the growth process of new bone cross-section by a series of continuous and discrete circles. Based on the definition and assumptions of the bone cross-section, three evaluation indexes are proposed to assist the clinician in critically comparing and analyzing the feasibility of preoperatively correction approaches. A motor-driven parallel external fixator (MD-PEF) is developed to verify the proposed characterization approach. Finally, the features of the generated correction paths are compared and analyzed based on three correction methods. The results show that the proposed method can well present the growth process of bone cross-section and can detect the overlap phenomenon between bone cross-sections. And the approach of joint adjustment for equal bone distraction can generate a smooth correction path, uniform distraction rate and effectively avoid the overlap of bone cross-sections. This study is an important addition to facilitating the development of deformity correction techniques.

Speech intelligibility of the diastratic varieties of Philippine English

The rise of English globalization has prompted speech production variations that reveal the cultural and social backgrounds of the different speakers. However, intelligibility issues of the different varieties have also become a concern. Thus, the present study attempted to assess the intelligibility of Philippine English (PE) diastratic varieties’ speech recordings produced by local Cebuano speakers. Further, it aimed to specifically evaluate the speakers’ production differences, rate the intelligibility of the language varieties, and determine the effect of language variety on the listener-evaluators in terms of intelligibility and distraction ratings. Using an exploratory sequential mixed method design, the speech participants in this study were carefully chosen through multistage sampling first by social class and then by phonological variations. The three final sample speakers out of the initial eighteen were finally categorized as acrolect, mesolect, and basilect. The evaluating groups included English language users from the USA, the Philippines, Korea, and Thailand, and each group represented a region in Kachru’s concentric circle of the World Englishes model. The results identified acrolect as the most intelligible variety followed by mesolect. Basilect, on the other hand, was considered very distracting to the evaluator groups, resulting in a significantly low intelligibility score. Thai evaluators gave the lowest intelligibility ratings, which may be attributed to two factors, L1 interference and unfamiliarity of L2 variation. Finally, future directions and implications in the classroom and industry are stated to create a sense of cultural awareness and to promote a deeper intercultural understanding that comes with international intelligibility.

Osmotic pump with potential for bone lengthening distracts continuously in vitro and in vivo.

In pediatric orthopedics, long bone lengthening procedures are routinely performed using manual, motorized or magnetically controlled implants. This study aims to prove expansion of a newly designed osmotic pump prior to long bone lengthening in living organisms and to rule out any complications related to in vivo conditions, such as congestion of the semipermeable membrane, local infection, or lack of water to drive the osmotic pump, as well as to compare in vivo and in vitro expansion data. Osmotic pumps, which were designed to distract a plate osteosynthesis, were inserted in the dorsal paraspinal musculature of four piglets. To compare the performance of the pumps in in vivo and in vitro conditions, another set of pumps was submerged in physiologic saline solution at different temperatures. The lengthening progress was measured radiographically and sonographically in the study animals. Both, in vitro and in vivo tested osmotic pumps started distraction after an intended rest phase of four days and distracted evenly over the following twelve days. No complications, clogging or damages occurred. However, we observed a temperature dependency of the distraction rate ranging from 0.98 mm/day at 39°C to 1.10 mm/day at 42°C. With a second setup, we confirmed that the distraction rate differed by 72% within a measured temperature interval of 14° C. The data presented here confirm that the novel osmotic pump showed comparable lengthening characteristics in vivo and in vitro. No complications, such as congestion of the semipermeable membrane, local infection, or lack of water to drive the osmotic pump were observed. Thus, osmotic pumps may have great potential in future applications such as long bone lengthening procedures, where continuous distraction probably provides a better bone quality than intermittent lengthening procedures. The fact that one pump failed to elongate in each condition, highlights the importance of technical improvement, but also demonstrates that this was not due to different circumstances within the in vivo or in vitro condition.

The accordion technique enhances bone regeneration via angiogenesis factor in a rat distraction osteogenesis model.

Objective: The purpose of this study was to observe the effect of the accordion technique (AT) during the distraction phase on chondrogenesis and bone regeneration in a rat femoral distraction osteogenesis (DO) model, and investigate its potential mechanism for reducing the total treatment time of DO. Methods: Fifty-four male Sprague-Dawley (SD) rats that were specific-pathogen-free (SPF) were subjected to DO surgery on the right femur. The distraction rate was 0.5mm/day for 10days, following a latency period of 5days. Rats were randomly divided into Control (no AT, n = 18), Group LA (low amplitude with AT, n = 18), and Group HA (high amplitude with AT, n = 18) according to different AT protocols in the distraction phase. Rats were respectively euthanized by anesthesia overdose at 2, 4 and 6weeks of the consolidation phase, and the femurs were harvested. Digital radiography, micro-computed tomography (micro-CT), biomechanical tests, and histomorphological analysis were used to assess the quality of regenerated bone in the distraction area. Results: Digital radiographic, micro-CT, biomechanical tests, and histological analysis revealed an increase in early-stage callus formation (p < 0.05) and improved blood supply to the callus tissue in Group LA, as compared to both the Control and Group HA. The enhanced differentiation of fibrous and cartilaginous tissue into bone tissue was also observed in Group LA, leading to improved strength and stiffness (p < 0.05) of the regenerated bone at 6weeks of the consolidation phase. The angiogenic (hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF), p < 0.05) and osteogenic (runt-related transcription factor 2 (RUNX2), osteocalcin (OCN) and osteopontin (OPN), p < 0.05) biomarkers were higher expressed in Group LA at 2 and 4weeks of consolidation phase, whereas decreased at 6 weeks of consolidation phase. Conclusion: The application of AT with low amplitude during the distraction phase can enhance chondrogenesis and bone regeneration by activating the angiogenesis factor pathway and upregulating the expression of osteogenic-related biomarkers such as HIF-1α, VEGF, RUNX2, OCN, and OPN.

Current global research on mandibular defect: A bibliometric analysis from 2001 to 2021.

Background: Mandibular defects can result from congenital deformities, trauma, tumor resection, and osteomyelitis. The shape was irregular because the lower jaw was radians. This involves teeth and jaw functions; therefore, the difficulty of bone repair is greater than that in other body parts. Several standard treatments are available, but they result in various problems, such as difficulties in skin flap transplantation and possible zone dysfunction, artificial material boneless combining ability, and a long treatment period. This study aimed to introduce the present status of research on mandibular defects to analyze the current introduction and predict future research trends through a bibliometric study. Methods: From 2001 to 2021, publications on mandibular defects were collected for bibliometric visualization using VOSviewer, CiteSpace, and Scimago Graphica software based on the Web of Science Core Collection. Results: This study analyzed 4,377 articles, including 1,080 published in the United States, 563 in China, and 359 in Germany, with an increase in the number of articles published over the past 20 years. Wikesjoe and Ulf Mai E had the most publications (p = 36) and citations (citations = 1,553). Shanghai Jiaotong University published the highest number of papers among the research institutions (p = 88). The most productive journal was Journal of Oral and Maxillofacial Surgery, and the cited literature was primarily classified as dentistry, dermatology, and surgery. Cluster Analysis of Co-occurrence Keywords revealed that highest number of core words were mandibular defects, mandibular reconstruction, and bone regeneration. The highest cited words were head and neck cancer, accuracy, and osteogenic differentiation. High-frequency terms of Cluster Analysis of References were osteosynthesis plate, tissue engineering, and rapid distraction rate. Conclusion: Over the past 20years, the number of studies on mandibular defects has gradually increased. New surgical procedures are increasingly being used in clinical practice. Current frontier topics mainly focus on areas such as computer-aided design, 3D printing of osteotomy and reconstruction guide plates, virtual surgical planning, and bone tissue engineering.

Development and principles of intramedullary and extramedullary segmental bone transport: overview and clinical results

Segmental bone transport using intramedullary or extramedullary techniques is one of the most commonly used procedures for bone defect management in the diaphyseal region of long bones. The purpose of this work is to provide an overview of the historical development and general principles as well as the current status of extramedullary and intramedullary techniques of bone segment transport. In addition, own results on internal segmental bone transport are presented. Aretrospective database analysis included all patients between May 2019 and January 2021 who underwent segmental bone transport via afully implantable intramedullary segment transport nail system. In addition to the radiological outcome, the clinical outcome was assessed using the lower extremity functional scale (LEFS). A total of 9 patients (8male, 1female; age 41.7 ± 3.9years) could be included. The cause of the segmental bone defect was chronic fracture-related infection in all cases. The segmental defect size was 62 ± 10 mm. Sufficient bridging of the bone defect was achieved in all patients, with amean distraction rate of 0.9 ± 0.1 mm per day. Bony consolidation of the regeneration was achieved after 292 ± 57days, and final bony consolidation of the docking zone was achieved after 469 ± 116 days. At 22 ± 3months after implantation of the segmental transport nail, the LEFS demonstrated aresult of 59 ± 4points. No recurrence of infection or regeneration failure occurred. The aim of treating segmental bone defects, in addition to reconstructing aload-bearing bone, is to restore correct joint angles, leg length, and leg axis without torsional deviation and can be achieved via classical external segmental bone transport. In recent years, internal segmental bone transport has been developed as an alternative. It remains to be seen whether the preliminary and reproducibly good clinical and radiological results of segmental transport nails can be confirmed for widespread use in the future.

Progress on knee cartilage repair by knee joint distraction

Knee joint distraction is a new technology for the treatment of knee osteoarthritis in recent years. It could reduce knee pain and improve knee function, which is inseparable from the role of cartilage repair. The mechanism and influencing factors of knee joint distraction in repairing cartilage are the focus of current research. In this paper, the author reviewed literature and found that knee joint distraction could reduce knee joint load and provide a appropriate mechanical environment for cartilage repair, and it is resulting hydrostatic pressure fluctuation in the knee joint not only helps cartilage to absorb nutrients, but also promotes cartilage formation genes and inhibits cartilage matrix degrading enzyme gene expression. In addition, knee joint distraction creates conditions for synovial mesenchymal stem cells to be collected to cartilage injury, and improves ability of synovial mesenchymal stem cells to proliferate and differentiate into a chondrogenic lineage. Knee joint distraction could reduce inflammatory reaction and cartilage injury of knee joint by reducing content of inflammatory factors and inhibiting expression of inflammatory genes. At present, it is known that the factors affect repair of cartilage by knee joint distraction include, increasing weight-bearing activity and height and time of distraction is helpful for cartilage repair, male patients and patients with higher severity of knee osteoarthritis have better cartilage repair effect after knee joint distraction.The better efficacy of cartilage repair on the first year after knee joint distraction predicts a higher long-term survival rate of knee joint distraction with knee preservation. However, the research on the above hot spots is only at the initial stage and further exploration is still needed, in order to better guide clinical application of knee joint distraction.

Assessment of Driver Distraction at Work Zones with Portable Rumble Strip Deployments in Texas

The objective of this research was to assess the extent of distracted driving occurring on roadways in Texas, U.S., as drivers approach a work zone and the extent to which portable rumble strips (PRS) may influence those rates. The research team utilized direct field observations of drivers approaching work zones at several Texas work zones. At each work zone, team members positioned themselves near the location of the upstream set of PRS. Team members also collected observational data at a second location downstream from that initial PRS location. The results of the field studies showed that nearly one in five motorists are visually distracted in some manner while driving as they approach a work zone. The studies also showed that this rate of visual distraction decreased at distances closer to the work zone. Observations of distracted drivers as they passed over the PRS indicate that at least some of that decrease in distraction over distance was because of the presence of the PRS. Data were not sufficient to determine conclusively how long the distraction-reducing effects of PRS last. However, data from one site suggest that the effect was limited to the first 1,500 ft after traversing the PRS.

Treatment of Severe Knee Flexion Contracture After Below Knee Amputation Using Hinged Ilizarov Ring External Fixator

Flexion contracture of the knee is a common complication found after Below Knee Amputation (BKA). This condition is caused by muscle imbalance and prolonged stump malpositioning after BKA. Acute surgical correction of this deformity associated with high rates of complications.A 39-years-old man with chief complaint flexion contracture after BKA 3 months before. Physical examination showed flexion contracture deformity with knee range of motion at 90° to 120° with no possibility of further knee extension. This condition prevented him to use prosthesis and start walking exercises. Gradual correction of flexion deformity was performed using hinged Ilizarov ring external fixator with the rate of distraction was 1mm/day to prevent soft tissue and neurovascular complications. After 90 days of distraction, full extension of the knee joint was achieved with no complications.Gradual correction of knee flexion contracture using hinged Ilizarov device greatly reduced the complications risk of acute deformity correction with open surgery. This technique provides more advantage of minor operative trauma with a gradually controlled correction, permitting the soft tissue to regenerate, thus lowering the risk of neurovascular complications.

Biomechanical Testing of a Novel Device for Sutureless Nerve Repair.

Suboptimal nerve end alignment achieved with conventional nerve repair techniques may contribute to poor clinical outcomes. In this study, we introduce Nerve Tape®, a novel nerve repair device that integrates flexible columns of Nitinol microhooks within a biologic backing to entubulate, align, and secure approximated nerve ends. This study compares the repair strength of Nerve Tape with that of conventional microsuture repairs. Thirty small (2 mm) and 30 large (7 mm) diameter human cadaveric nerves were transected and repaired utilizing Nerve Tape or appropriate microsuture technique. Biomechanical testing was performed using a horizontal tensile tester. The repaired nerves were loaded until failure at a distraction rate of 40 mm/min, and the maximum failure load was determined. In the small nerve groups, the load-to-failure for Nerve Tape repairs (2.33 ± 0.66 N) was significantly higher than for suture repairs (1.22 ± 0.52 N; p < 0.05). In the large nerve groups, no significant difference in load-to-failure was found between Nerve Tape (7.45 ± 2.66 N) and suture repairs (5.82 ± 1.59 N: p = 0.12). Suture repairs tended to fail by rupture, whereas Nerve Tape failures resulted from microhook pullout. Nerve Tape is a novel nerve coaptation device that provides mechanical repair strength equal or greater to clinically relevant microsuture repairs.

Experimental and clinical studies on the reduction of bone lengthening terms at the Ilizarov Center

Introduction The list of pathological conditions that need surgical correction of bone length is very long. In the literature on the topic under discussion, it is reported that the best results are obtained by lengthening according to the Ilizarov method. But many surgeons are not satisfied with the long duration of external fixation, which requires a large number of adjustments and patient compliance. The aim of this work is a analysis of the modern technologies for limb lengthening that actually shorten the time of osteosynthesis using the apparatus for external fixation. Materials and methods Literary sources have been analyzed since the first publication on limb lengthening according to Ilizarov in 1963. The search was carried out in the databases of the RSCI, NCBI Pubmed, Medline. The developments of the employees of the Ilizarov Center are presented. Results An analysis of the literature showed that the fixation units of the apparatus, units for providing movement for distraction, compression and correction of angles have been improved. The invasiveness of the surgical intervention is minimized. Best results can be obtained using automatic lengthening. The Ilizarov Center has developed and experimentally proven methods for reducing the period of distraction and the period of fixation with the apparatus. We combined three factors: an increased round-the-clock distraction rate (2 or 3 mm) with a motorized distractor adjusted to the Ilizarov frame and fixation reinforcement along with regeneration stimulation with HA-coated intramedullary wires in our experimental and clinical trials. This technology has easily conquered a number of clinical practices in Russia, France and Serbia. Conclusion Experimental and clinical substantiation of a two- or three-fold increase in the rate of automated distraction in the conditions of intramedullary reinforcement with a bioactive implant can drastically reduce not only the time of the distraction period, but also the duration of the fixation period with the Ilizarov apparatus.

Total flavonoids of Rhizoma Drynariae enhances CD31hiEmcnhi vessel formation and subsequent bone regeneration in rat models of distraction osteogenesis byactivating PDGF‑BB/VEGF/RUNX2/OSX signaling axis.

Total flavonoids of Rhizoma Drynariae (TFRD), extracted from the kidney-tonifying Traditional Chinese medicine Rhizoma Drynariae, can be effective in treating osteoporosis, bone fractures and defects. However, the pharmacological effects of TFRD on the specific vessel subtype CD31hiEmcnhi during distraction osteogenesis (DO) remains unclear. The present study aimed to investigate the effects of TFRD on CD31hiEmcnhi vessels in a rat model of DO. In the present study, tibial DO models were established using 60 rats with a distraction rate of 0.2 mm per day for 20 days. Co-immunofluorescence staining of CD31 and endomucin (Emcn) was conducted to determine CD31hiEmcnhi vessels. Radiographic, angiographic and histological analyses were performed to assess bone and vessel formation. Tube formation, alkaline phosphatase (ALP) and Von Kossa staining assays were performed to test angiogenesis of endothelial precursor cells (EPCs) and osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs). Additionally, expression levels of platelet-derived growth factor (PDGF)-BB, VEGF, runt-related transcription factor 2 (RUNX2) and Osterix (OSX) were determined by western blotting and reverse transcription-quantitative PCR. The in vivo assays demonstrated that TFRD markedly promoted CD31hiEmcnhi vessel formation during DO, whereas PDGF-BB neutralizing antibody suppressed vessel formation. Furthermore, the ALP, Von Kossa staining and tube formation assays indicated that TFRD notably elevated the angiogenic capacity of EPCs and osteogenic capacity of BMSCs under stress conditions, which was significantly suppressed by blocking PDGF-BB. The protein and mRNA levels of PDGF-BB, VEGF, RUNX2 and OSX were upregulated by TFRD, but downregulated by blocking PDGF-BB. Thus, TFRD could facilitate CD31hiEmcnhi vessel formation and subsequently enhance angiogenic-osteogenic coupling to regenerate bone defects during DO via the PDGF-BB/VEGF/RUNX2/OSX signaling axis, which indicated that CD31hiEmcnhi vessels could be a potential novel therapeutic target for DO, and TFRD may represent a promising drug for promoting bone regeneration in DO by increasing CD31hiEmcnhi vessels.

Accelerated cranial distraction protocol for one-piece fronto-orbital distraction osteogenesis without bandeau in patients with craniosynostosis

This study aimed to compare the bony relapse ratios of standard and accelerated distraction protocols (ADP) in one-piece fronto-orbital distraction osteogenesis (DO).Patients with unilateral or bilateral coronal synostoses who underwent one-piece fronto-orbital DO were included. The accelerated cranial distraction protocol included a 3-day latency period and a distraction rate of 1–2 mm/day, followed by a 4-week consolidation period. Intracranial volume was measured using computed tomography (CT) before the surgery, at the end of the consolidation period, and 1 year after the removal of distractors. The intracranial volume changes and relapse ratios were calculated.This study included 32 patients; of these, 16 were included in each of the ADP and standard protocol (SP) groups. The mean ages were 1.4 years and 1.6 years in the ADP and SP groups, respectively (p = 0.895). In the ADP and SP groups, the expanded volumes were 270.9 ± 90.3 cm3 and 284.6 ± 149.7 cm3 (p = 0.91) and the growth-corrected expanded volumes were 162.1 ± 67.5 cm3 and 177.1 ± 105.2 cm3, respectively (p = 0.867). The relapse and growth-corrected relapse ratios showed no significant differences between the two groups, suggesting similar stability between the two protocols. The relapse ratios were 7.1 ± 4.8% and 7.3 ± 5.0% (p = 0.91) and the growth-corrected relapse ratios were −3.0 ± 3.3% and −2.4 ± 2.7%, respectively (p = 0.498).Within the limitations of the study, it seems that the ADP can shorten the distraction period without compromising stability. This may contribute to resolving the disadvantages and highlighting the advantages of DO.

Experimental testing and histology result of the continuous distraction device application at the various rates

Relevance. In modern maxillofacial surgery, the technique and mechanism of compression-distraction osteogenesis are still relevant as an alternative method of obtaining bone tissue in complex clinical cases. All types of compression-distraction devices used in practice have only a mechanical drive, i.e., fragments of bone tissue are separated fractionally in such devices, creating uneven tension in the newly formed regenerate, which leads to its incomplete ossification. We have developed, tested on a stand and tested in an animal experiment a distraction appliance operating on the principle of continuous separation of bone fragments, having a piston-type motor, activation of which occurs during an electrochemical reaction triggered and controlled by software with a feedback kit.Material and methods. The stages of our research were as follows: development of devices and electronics, bench tests, creation of clinical models of an automated continuous distraction device; clinical trials of devices, their placement in the experiment animals (dogs), testing of electronic continuous distraction devices at various rates (1 mm, 2 mm, 3 mm per day); morphological and clinical and radiographic evaluation of the bone regenerates, and development of clinical recommendations for the device application and distraction rates.Results. The received data based on the available clinical and morphological-radiographic picture between the bone fragments distracted by the device prove the possibility of regenerate formation during continuous distraction at various rates, when constant atraumatic stretching of the regenerate is maintained, without its transition to a fractional deformation similar to a pre-plastic one. At the same time, the analysis of morphological studies showed the best histomorphological regenerate maturity obtained by continuous distraction at a rate of 2 mm. per day.Conclusion. We can recommend the introduction of the automated continuous distraction device created by our experienced group into practical medicine at a distraction rate of 2 mm. per day.

Alveolar ridge augmentation in mandible by use the modified distractor.

Objective: The aim of the present study was to evaluate the horizontal and the vertical alveolar distraction osteogenesis using modified alveolar distractor.Study design: The sample consisted of 7 patients presenting horizontally and vertically deficient edentulous ridges were treated by distraction osteogenesis with a modified Alveolar distractor. The surgical procedure was carried out with the patient under local anesthesia. After the osteotomy was performed with pizosurgery, the distractor was placed on the segmental bone over the gingiva for 3 months. The rate of distraction was 0.5 mm/twice a day.Results: The mean of horizontal alveolar before using the distractor was 4.70 mm (SD 0.31 mm) The mean of horizontal alveolar after using the distractor was 8.30 mm (Sd 0.59 mm). The mean of actual gain in bone horizontal at the end of the distraction period was 3.58 mm (SD 0.15 mm). The mean of height alveolar before using the distractor was 6.67 mm (SD 0.46 mm) The mean of height alveolar after using the distractor was 12.59 mm (SD 0.52 mm). The mean of actual gain in bone height at the end of the distraction period was 5.92 mm (SD 0.25 mm).Conclusion: It was concluded that the modified alveolar distractor seems to be an effective to treat horizontal and vertical alveolar ridge deficiencies, and distraction osteogenesis can be considered a safe and effective procedure for gaining bone in the horizontal and the vertical dimension of the alveolar.