Enhanced Bone Regeneration through Regulation of Mechanoresponsive FAK-ERK1/2 Signaling by ZINC40099027 during Distraction Osteogenesis.

Background: Focal adhesion kinase (FAK) is activated by mechanical stimulation and plays a vital role in distraction osteogenesis (DO), a well-established but lengthy procedure for repairing large bone defects. Both angiogenesis and osteogenesis contribute to bone regeneration during DO. However, the effects of ZINC40099027 (ZN27), a potent FAK activator, on angiogenesis, osteogenesis, and bone regeneration in DO remain unknown. Methods: The angiogenic potential of human umbilical vein endothelial cells (HUVECs) was evaluated using transwell migration and tube formation assays. The osteogenic activity of bone marrow mesenchymal stem cells (BMSCs) was assessed using alkaline phosphatase (ALP) and alizarin red s (ARS) staining. Additionally, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunofluorescence staining were used to assay angiogenic markers, osteogenic markers, and FAK-extracellular signal-regulated kinase 1/2 (ERK1/2) signaling. In vivo, a rat tibia DO model was established to verify the effects of ZN27 on neovascularization and bone regeneration using radiological and histological analyses. Results: ZN27 promoted the migration and angiogenesis of HUVECs. Additionally, ZN27 facilitated the osteogenic differentiation of BMSCs, as revealed by increased ALP activity, calcium deposition, and expression of osteogenesis-specific markers. The ERK1/2-specific inhibitor PD98059 significantly hindered the effects of ZN27, suggesting the participation of FAK-ERK1/2 signaling in ZN27-enhanced angiogenesis and osteogenesis. As indicated by improved radiological and histological features, ZN27 induced active angiogenesis within the distraction area and accelerated bone regeneration in a rat DO model. Conclusion: Our results show that ZN27 targets FAK-ERK1/2 signaling to stimulate both angiogenesis and osteogenesis, and ZN27 accelerates bone regeneration in DO, suggesting the therapeutic potential of ZN27 for repairing large bone defects in the mechanobiological environment during DO.

Early posterior vault distraction osteogenesis changes the syndromic craniosynostosis treatment paradigm: long-term outcomes of a 23-year cohort study.

BACKGROUND: Early surgical management of syndromic craniosynostosis varies widely between centers, with patients typically undergoing multiple intracranial procedures through childhood. This study evaluates the long-term impact of early posterior vault distraction osteogenesis (PVDO) versus conventional treatment paradigms on the number and timing of subsequent craniofacial procedures. METHODS: We retrospectively analyzed the longitudinal operative patterns of patients with syndromic craniosynostosis treated from 2000 to 2023 with greater than five years of follow-up. Outcomes of patients who underwent early PVDO and conventional vault reconstruction were compared. RESULTS: Fifty-five patients met the inclusion criteria (30 PVDO and 25 conventional). Age at initial vault surgery was similar between the PVDO and conventional cohorts (7.6 vs. 8.8 months), as were baseline craniometrics (p > 0.05). Multiple fronto-orbital advancement (FOA) procedures were performed in only 1/30 (3%) PVDO-treated patient versus 12/25 (48%) conventionally-treated patients (p < 0.001). Twelve (40%) PVDO-treated patients did not undergo FOA at all. Among patients with Apert and Crouzon syndromes, fewer PVDO-treated patients required FOA prior to midface surgery (33% vs. 92%, p = 0.004) or repeat FOA (6% vs. 50%, p = 0.005) compared to conventionally-treated patients. Among patients with Muenke and Saethre-Chotzen syndromes, a similar proportion of patients required FOA in the PVDO and conventional cohorts (91% vs. 100%, p = 0.353), though no PVDO-treated patients required repeat FOA (0% vs. 44%, p = 0.018). CONCLUSIONS: Early PVDO is associated with a reduction in the high burden of both FOA and, critically, revisionary frontal procedures which are commonly seen in conventionally-treated patients with syndromic craniosynostosis.

Apert syndrome: neurosurgical outcomes and complications following posterior vault distraction osteogenesis.

PURPOSE: Posterior vault distraction osteogenesis (PVDO) has been utilized during the past 15 years to treat a variety of clinical features commonly presented by patients with Apert syndrome. The objective of this study is to determine the efficacy of PVDO in addressing both elevated intracranial pressure (ICP) and ectopia of the cerebellar tonsils (ECT) in young Apert patients. In addition, we aimed to determine the prevalence of hydrocephalus in Apert syndrome patients who underwent PVDO. METHODS: A retrospective study was made with a cohort of 40 consecutive patients with syndromic craniosynostosis (SC), previously diagnosed with Apert syndrome, who underwent PVDO between 2012 and 2022, and thereafter received at least 1 year of follow-up care. Demographic data and diagnosis, along with surgical and outcome data, were verified using medical records, clinical photographs, radiologic examination, and interviews with the parents of all cohort patients. RESULTS: The average patient age when PVDO was performed was 12.91 ± 10 months. The average posterior advancement distance achieved per patient was 22.68 ± 5.26 mm. The average hospital stay per patient was 3.56 ± 2.44 days. The average absolute and relative blood transfusion volumes were 98.47 ml and 17.63 ml/kg, respectively. Although five patients (14%) presented ECT preoperatively, this condition was completely resolved by PVDO in three of these five patients. One of the three patients whose ECT had completely resolved presented syringomyelia postoperatively, requiring subsequent extra dural foramen magnum decompression. All of the remaining four patients were asymptomatic for ECT for at least 1 year of follow-up, and none of these four patients required any additional treatments to address ECT. Two patients presented hydrocephalus requiring ventriculoperitoneal shunt placement. CONCLUSIONS: This study demonstrates that PVDO both reduces diagnosed elevated ICP symptoms and is partially effective in treating ECT in Apert syndrome patients. Hydrocephalus in Apert syndrome is an uncommon feature. The effectiveness of PVDO in addressing hydrocephalus is uncertain.

Monitoring of Home Respiratory Polygraphy During Mandibular Distraction Osteogenesis Succeeded by LeFort I Osteotomy in Adult Patients With Obstructive Sleep Apnea.

BACKGROUND: Bilateral internal ramus distraction (BIRD) is now part of select protocols for treating obstructive sleep apnea (OSA). Introducing a home monitoring protocol offers a valuable alternative to overnight laboratory polysomnography (PSG). PURPOSE: The purpose of this study was to evaluate and compare OSA parameters obtained via home respiratory polygraphy (HRP) and hospital PSG in a cohort of patients undergoing mandibular distraction for OSA management. STUDY DESIGN, SETTING, SAMPLE: Hospital Universitario La Princesa (Madrid) researchers conducted a prospective cohort study with patients diagnosed with moderate (apnea-hypopnea index (AHI) = 15 to 30) to severe (AHI>30) OSA undergoing BIRD followed by LeFort maxillary osteotomy. Exclusion criteria were as follows: severe systemic diseases, central apneas, smoking, poor dental hygiene, or prior OSA interventions. PREDICTOR VARIABLE: The predictor variable was PSG and HRP techniques. MAIN OUTCOME VARIABLES: The main outcome variable comprises a collection of OSA parameters, including the AHI, oxygen desaturation index (ODI), and time spent below 90% oxygen saturation (T90). These data were measured both before and after distraction, as well as after 6 mm, 9 mm, and 12 mm of mandibular distraction. COVARIATES: The covariates were age, sex, cardiovascular risk parameters, and the Epworth sleepiness scale. ANALYSES: Pearson's correlation analyzed AHI, ODI, and T90 values from PSG and HRP. Wilcoxon Signed Rank-Sum Test compared 2 distraction stages, and the Friedman Test evaluated 3 stages (P < .05). Multiple regression analysis assessed if covariates were independent risk factors for postoperative persistent OSA. RESULTS: The study included 32 patients (25% with moderate and 75% with severe OSA). Final AHI was 10.9 ± 8.9 (events/hour) with HRP, compared to 15.2 ± 13.4 with PSG (r = 0.7, P < .05). ODI was 9.0 ± 8.1 (des/h) with HRP and 8.7 ± 9.5 with PSG (r = 0.85, P < .05). T90 was 1.6 ± 2.2 with HRP and 1.3 ± 3.0 with PSG (r = 0.6, P < .05). Based on HRP data, AHI improved from D1 (34.0 ± 19.5) to D2 (20.8 ± 14.1) and D3 (12.5 ± 10.4) (P < .05). ODI decreased from D1 (26.1 ± 19.0) to D2 (16.0 ± 12.6) and D3 (9.4 ± 8.8) (P < .05). T90 reduced from D1 (8.2 ± 12.6) to D2 (4.1 ± 5.2) and D3 (1.9 ± 2.8) (P < .05). Multiple regression analysis of comorbidities produced nonsignificant results. CONCLUSION AND RELEVANCE: Monitoring BIRD through HRP has demonstrated efficacy in yielding results that align with PSG.

Bone Volume Analysis and Associated Influencing Factors in Mandibular Distraction Osteogenesis: A Retrospective Analysis.

BACKGROUND: Distraction osteogenesis is a progressively popular technique for maxillofacial bone reconstruction, but there is a notable gap in the analysis of bone volume within the distraction segment and the exploration of associated influencing factors. PURPOSE: The purpose of this study was to quantitatively analyze the new bone volume and the distraction gap volume in the three-dimensional (3D) model and explore the influencing factors associated with the percentage of the new bone volume to the distraction gap volume. STUDY DESIGN, SETTING, SAMPLE: This retrospective study included patients who underwent maxillofacial distraction osteogenesis treatment at the West China Hospital of Stomatology between 2014 and 2022, utilizing the mandibular distractor (Cebei, Ningbo, China). Exclusion criteria encompassed individuals with incomplete clinical or radiographical records as well as those who loss to follow-up. PREDICTOR VARIABLE: The predictor variables were age, sex, diagnosis, consolidation period duration, distraction modality, osteotomy area, distraction gap volume, and proximal bone segment volume. MAIN OUTCOME VARIABLE(S): The outcome variable was osteogenic effect which defined as the percentage of the new bone volume to the distraction gap volume in the 3D model. COVARIATES: Not applicable. ANALYSES: T-tests were used to describe categorical variables, and Pearson correlation analysis was used to describe continuous variables. Linear regression was employed to assess the predictiveness of variables for osteogenic effect. Data are described as mean ± standard deviation; statistical significance was established at a P value < .05. RESULTS: The study sample contained 35 patients(11 males and 24 females) with a mean age of 21.17 ± 11.82 years (range: 5 to 47 years) were included. The mean osteogenic effect of all samples was 78.89 ± 24.70%. Multiple linear regression models confirmed that the osteogenic effect was significantly influenced by the distraction gap volume (P = .003), proximal bone segment volume (P = .009), osteotomy area (P = .034), diagnosis (P = .004), and distraction modality (P = .021). CONCLUSION AND RELEVANCE: The percentage of new bone mass to simulated volume based on 3D model measurement can serve as an effective quantitative indicator for evaluating the osteogenic effect; our study demonstrates that distraction gap volume, proximal bone segment volume, osteotomy area, diagnosis, and distraction modality can statistically significantly influence the osteogenic effect.

Mandibular Distraction in Patients With Pierre Robin Sequence: A Multisurgeon Experience.

OBJECTIVE: Mandibular distraction osteogenesis (MDO) is rapidly becoming a standard of care for management of patients with severe Pierre Robin sequence. The tongue is brought forward to alleviate airway obstruction. This study will look at an institutional, multisurgeon experience with MDO over 10 years. DESIGN: A retrospective chart review was conducted. SETTING: All patients who underwent MDO at the authors' institution from 2012 to 2022 were included. Three craniofacial surgeons performed all interventions. PATIENTS: Demographics, preoperative and postoperative respiratory and feeding status, and distraction data were collected for 27 patients meeting inclusion criteria. MAIN OUTCOME MEASURES: Primary outcomes were avoidance of a gastrostomy tube, avoidance of a tracheostomy, discharge from hospital on room air, and complications. A significance value of 0.05 was utilized. RESULTS: The average age at MDO was 135 days, mean activation phase was 13.6 days, mean distraction length was 14.9 mm, and mean consolidation phase was 64.2 days. A longer activation phase was associated with discharge with a gastrostomy tube and a shorter activation phase was associated with discharge on full oral feeds. The ability to discharge on room air was associated with a shorter latency phase, shorter activation phase, and decreased distance of distraction. CONCLUSIONS: The goal of MDO is to achieve full oral feeds with no respiratory support. Several different latency periods were used in this study, and a short latency period was demonstrated to be safe.

Posterior Vault Distraction in the Acute Setting.

ABSTRACT: Posterior vault distraction osteogenesis (PVDO) has been shown to resolve acute intracranial hypertension (AIH) while carrying an acceptable perioperative morbidity profile. PVDO has been associated with symptomatic improvement and fewer surgeries in those requiring ventriculoperitoneal shunts. The authors' experience using PVDO as an acute intervention is presented, demonstrating its safety and efficacy for management of AIH. Four cases of children with craniosynostosis that underwent PVDO in the acute setting are outlined. All patients presented with papilledema and symptoms of AIH. One patient with slit ventricle syndrome (SVS) presented with a nonfunctioning shunt following multiple shunt revisions. No intraoperative complications during distractor placement or removal were reported. Distraction protocol for all patients began on postoperative day 1 at 1-2 mm per day, resulting in an average total distraction of 30.25 mm. For the 3 cases with no shunt, the average length of stay was 7 days. As part of the planned treatment course, the patient with SVS required externalization of the shunt during distraction followed by early distractor removal and planned shunt replacement. One case of surgical site infection (in an immunocompromised patient) required premature distractor removal during the consolidation period. Computed tomography (CT) in all patients indicated increased intracranial volume following distraction, and symptomatic improvement was reported. Six-month follow-up showed resolution of papilledema in all patients. The authors' experience using PVDO in the acute setting is reported, alongside a review of current literature, in order to provide supporting evidence for the efficacy of PVDO as a tool for resolving AIH.

Reconstruction of Bony Defects With Motorized Intramedullary Nails After Tumor Resection.

Motorized intramedullary lengthening nails allow for transport of a bone segment for limb lengthening, deformity correction, healing of nonunion, and intercalary distraction osteogenesis. Resection of tumors involving the bone can result in substantial defects that require reconstruction. Use of these nails allows for a biologic reconstruction with the incorporation of allograft or by distraction osteogenesis. Limb lengthening after an internal hemipelvectomy where the hip joint is resected can be performed to improve gait, decrease pain, and prevent the need for a custom shoe or shoe lift. Using these nails in compression aids the incorporation of intercalary allografts and prevents stress shielding and stress risers within the graft when compared with plating. It also allows for a subsequent lengthening of the limb using the same implant. Plate-assisted bone segment transport or the use of a bone transport nail allows for a true biologic reconstruction of an intercalary defect using distraction osteogenesis. These implants provide the orthopaedic oncologist with more options for reconstruction and the potential to improve the function and outcomes of their patients.

Innovative Hip Distraction Approaches for Total Hip Arthroplasty in Crowe IV Developmental Dysplasia or Similar High-Riding Patients.

BACKGROUND: Total hip arthroplasty (THA) for dislocated hips (Crowe IV dysplasia) presents unique challenges. Conventional approaches involve subtrochanteric osteotomies, but are complex with additional fixation and potentially lead to limb length discrepancies, nerve palsies, and other complications. An alternative strategy is a staged approach, where the femoral head (or remnant) is gradually lowered (distraction technique) to align with the true acetabulum over a period of time, followed by a second-stage anatomically acetabular-positioned THA. External fixation distraction and telescoping internal lengthening devices have been utilized to achieve preoperative alignment. We evaluated these techniques, including the types, time, and amount of distraction needed, as well as outcomes and complication rates. METHODS: In this retrospective case series, 14 patients (9 women, 5 men), who had a mean age of 32 years (range, 16 to 67), underwent staged surgical interventions using hip distraction using external fixators or internal lengthening devices for hip dysplasia and other pathologies (Perthes disease, osteonecrosis) in preparation for a second-stage anatomically placed THA. The mean follow-up duration for external-fixation patients was 10 years (range, 6.5 to 13.4). RESULTS: Staged treatment involved external fixators (n = 8) or internal lengthening devices (n = 6) with a device placement mean of 48 days (range, 42 to 71). The amount of distraction ranged from 6 to 12 cm. There were 2 patients who required uncomplicated revision of the internal lengthening devices, and another patient had a temporary peroneal nerve palsy. There was 1 patient who underwent an acetabular revision at 7 years. CONCLUSIONS: We focused on a challenging patient cohort that emphasizes the efficacy of staged interventions in managing Crowe Type IV dysplasia and similar cases. Favorable outcomes were found with the immediate transition to THA after device removal that effectively addressed soft-tissue contractures and femoral migration. Despite the need for further validation via larger, prospective studies, this innovative approach may pave the way toward optimizing this strategy for these difficult hip pathologies.

Jaw Thrust: A Simple Predictor of Success in Mandibular Distraction Osteogenesis.

BACKGROUND: The hypoplastic mandible in the congenital condition Pierre Robin sequence (PRS) displaces the base of the tongue posteriorly, which results in upper airway obstruction (UAO) that can potentially be corrected with mandibular distraction osteogenesis (MDO). Jaw thrust (JT) is routinely performed during evaluation of the airway; similar to MDO, it projects the mandible and tongue anteriorly to open the airway. The authors demonstrate that JT can be used as a criterion to predict successful MDO outcomes in infants with PRS. METHODS: The study was a single-center, retrospective chart review of infants diagnosed with PRS between 2016 and 2023. Data regarding their demographics, comorbid diagnoses, JT success, airway anomalies, laryngeal grade of view, apnea-hypopnea index, and perioperative course were statistically analyzed. RESULTS: Of the 16 patients included in the study, 11 had successful relief of their airway obstruction with JT and proceeded with MDO. The unsuccessful JT group had significantly greater proportions of females, birth prematurity, gastrostomies, tracheostomies, and longer hospital stays. In the successful JT group, both the mean laryngeal grade of view ( P =0.029) and mean apnea-hypopnea index ( P =0.025) improved significantly post-MDO. Post-MDO tracheostomy was also avoided in all but 1 patient who was not previously tracheostomized. CONCLUSIONS: There is no widely accepted algorithm to guide craniofacial surgeons on the optimal intervention for relieving UAO in infants with PRS. In our institutional experience, patients whose preoperative JT relieved UAO also successfully relieved UAO with MDO. In patients with PRS, JT may be a useful criterion for selecting appropriate candidates for MDO.

Mandibular Distraction Osteogenesis in Children and Adolescents: A Clinical and Radiographic Research Using Cone-Beam Computed Tomography.

AIM: The aim of this cross-sectional study was to evaluate, via cone-beam computed tomography, the long-term postoperative outcome in children treated with mandibular distraction osteogenesis. MATERIALS AND METHODS: All young patients treated with mandibular distraction osteogenesis (MDO), during a 16-year period, at the University Department of Oral and Maxillofacial Surgery of a Pediatric Hospital, were recalled, and various clinical and radiographic parameters were recorded. RESULTS: Eleven patients were included: 5 with hemifacial microsomia (HFM) and 6 with mandibular micrognathia. In all cases, MDO had been successful in regular follow-up and decannulation, soon after MDO, was achieved in all tracheostomy cases. The long-term result in cases of HFM was found stable, functionally and esthetically accepted, although less satisfactory than in regular follow-up; in micrognathia patients, relapse of different degrees was registered in 4 of 6 cases, without any need for tracheostomy though. Detailed and accurate information was obtained by cone-beam computed tomography (CBCT). The shape of the regenerated bone was irregular in HFM cases and relatively normal in the micrognathia cases. Quality of the regenerated bone was normal in all patients. The irregular shape registered in HFM cases did not compromise a safe orthognathic operation. CONCLUSIONS: Distraction osteogenesis remains an early treatment choice in cases of mandibular deformities. Long-term findings showed that there is a degree of relapse with growth, which was more obvious in mandibular micrognathia cases. Computed tomography contributes to detailed evaluation of changes at the distraction site.

Evaluation of simultaneous bilateral femoral distraction osteogenesis with antegrade intramedullary lengthening nails in achondroplasia with rhizomelic short stature: a retrospective study of 15 patients with a minimum follow-up of 2 years.

BACKGROUND AND PURPOSE: Bilateral femoral distraction osteogenesis in patients with achondroplasia is insufficiently reported. We aimed to perform the first study that exclusively analyzed simultaneous bilateral femoral distraction osteogenesis with motorized intramedullary lengthening nails via an antegrade approach in patients with achondroplasia focused on reliability, accuracy, precision, and the evolving complications. PATIENTS AND METHODS: In this retrospective singlecenter study we analyzed patients with achondroplasia who underwent simultaneous bilateral femoral lengthening with antegrade intramedullary lengthening nails between October 2014 and April 2019. 15 patients (30 femoral segments) of median age 14 years (interquartile range [IQR] 12-15) were available for analysis. The median follow-up was 29 months (IQR 27-37) after nail implantation. RESULTS: The median distraction length per segment was 49 mm (IQR 47-51) with a median distraction index of 1.0 mm/day (IQR 0.9-1.0), and a median consolidation index of 20 days/cm (IQR 17-23). Reliability of the lengthening nails was 97% and their calculated accuracy and precision were 96% and 95%, respectively. The most common complication was temporary restriction of knee range of motion during distraction in 10 of 30 of the lengthened segments. 1 patient was treated with 2 unplanned additional surgeries due to premature consolidation. CONCLUSION: The method is reliable and accurate with few complications.

Simultaneous correction of leg length discrepancy and angular deformity of the distal femur with retrograde Precice nails: a retrospective analysis of 45 patients.

BACKGROUND AND PURPOSE: Magnetically controlled motorized intramedullary lengthening nails (ILNs) can be employed for simultaneous correction of angular deformities of the distal femur and leg length discrepancy. This spares typical complications of external fixators but requires precise preoperative planning and exact intraoperative execution. To date, its results are insufficiently reported. We aimed to elucidate the following questions: (i) Is acute angular deformity correction and gradual femoral lengthening via a retrograde ILN a reliable and precise treatment option? (ii) What are the most common complications of treatment? METHODS: Acute angular deformity correction and subsequent gradual lengthening of the distal femur with retrograde ILN was retrospectively analyzed in 45 patients (median patient age: 15 years, interquartile range [IQR] 13-19 and median follow-up: 40 months, IQR 31-50). Outcome parameters were accuracy, precision, reliability, bone healing, and complications of treatment. RESULTS: The median distraction was 46 mm (IQR 29-49), median distraction and consolidation index 0.9 mm/day (IQR 0.7-1.0) and 29 days/cm (IQR 24-43), respectively. The median preoperative mechanical axis deviation (MAD) was 30 mm (IQR 23-39) in the varus cohort and -25 mm (IQR -29 to -15) in the valgus cohort and reduced to a mean of 8 mm (standard deviation [SD] 8) and -3 (SD 10), respectively. Accuracy, precision, and reliability of lengthening were 94%, 95% and 96%, respectively. Accuracy and precision of deformity correction were 92% and 89%, respectively. In total, 40/45 of patients achieved distraction with a difference of less than 1 cm from the initial plan and a postoperative MAD ranging from -10 mm to +15 mm. In 13/45 patients unplanned additional surgeries were conducted to achieve treatment goal with nonunion being the most frequent (4/45) and knee subluxation (3/45) the most severe complication. CONCLUSION: Acute deformity correction and subsequent lengthening of the distal femur with retrograde ILN is a reliable and accurate treatment achieving treatment goal in 89% but unplanned additional surgeries in 29% of patients should be anticipated.

Novel GNAI3 mutation in a Chinese family with auriculocondylar syndrome and treatment of severe dentofacial deformities: a 5-year follow-up case report.

BACKGROUND: Auriculocondylar syndrome (ARCND) is an extremely rare autosomal dominant or recessive condition that typically manifests as question mark ears (QMEs), mandibular condyle hypoplasia, and micrognathia. Severe dental and maxillofacial malformations present considerable challenges in patients' lives and clinical treatment. Currently, only a few ARCND cases have been reported worldwide, but most of them are related to genetic mutations, clinical symptoms, and ear correction; there are few reports concerning the treatment of dentofacial deformities. CASE PRESENTATION: Here, we report a rare case of ARCND in a Chinese family. A novel insertional mutation in the guanine nucleotide-binding protein alpha-inhibiting activity polypeptide 3 (GNAI3) was identified in the patient and their brother using whole-exome sequencing. After a multidisciplinary consultation and examination, sequential orthodontic treatment and craniofacial surgery, including distraction osteogenesis and orthognathic surgery, were performed using three-dimensional (3D) digital technology to treat the patient's dentofacial deformity. A good prognosis was achieved at the 5-year follow-up, and the patient returned to normal life. CONCLUSIONS: ARCND is a monogenic and rare condition that can be diagnosed based on its clinical triad of core features. Molecular diagnosis plays a crucial role in the diagnosis of patients with inconspicuous clinical features. We present a novel insertion variation in GNAI3, which was identified in exon 2 of chromosome 110116384 in a Chinese family. Sequential therapy with preoperative orthodontic treatment combined with distraction osteogenesis and orthognathic surgery guided by 3D digital technology may be a practical and effective method for treating ARCND.

Skeletal expansion via craniofacial distraction osteogenesis technique in syndromic craniosynostosis: impact on ophthalmic parameters.

BACKGROUND: This study aims to compare the changes in ophthalmic parameters among syndromic craniosynostosis patients who underwent craniofacial skeletal expansion procedures via distraction osteogenesis (DO). METHOD: A retrospective study was conducted involving syndromic craniosynostosis patients who underwent surgical expansion via the DO technique from the year 2012 to March 2022. Changes in six parameters which consist of visual acuity, refractive error, optic disc health, intraocular pressure, degree of proptosis and orbital volume were measured objectively pre and post-surgery. For categorical parameters, the Chi-square cross-tab test was done. Paired sample T-test was used for normally distributed variables. Wilcoxon signed-rank test was used for non-normally distributed data. RESULTS: Visual impairment was present in 21.4% of eyes before surgery and increased to 28.5% post-surgery. Three patients had changes of refractive error post-surgery with one developed hypermetropia, another developed anisometropia and the last had improvement to no refractive error. Two patients had optic disc swelling which was resolved post-surgery. Intraocular pressure changes were inconsistent post-surgery. All patients achieved a significant reduction in the degree of proptosis post-surgery. Orbital volume calculation using computed tomography (CT) scans shows a significant increase in volume post-surgery for all patients. CONCLUSION: Our study shows a significant increase in orbital volume post-surgery with a reduction in the degree of proptosis. Optic disc and nerve health improved after the surgery. Changes in terms of visual acuity, refractive error and IOP were inconsistent after the surgical intervention.

Determination of mandibular distraction osteogenesis most suitable parameters. An experimental study.

BACKGROUND: Distraction osteogenesis is a process of induced bone generation. Various protocols have been described for the management of the latency period, distraction speed and consolidation period, with greater or lesser success. OBJECTIVE: To better understand the process of mandibular distraction and establish the determining factors and their optimal times. MATERIAL AND METHODS: Twenty-seven dogs were studied, which had 54 distractors placed and that underwent unidirectional, bilateral mandibular distraction osteogenesis. The distraction processes were applied using six variants, two for each factor: latency period, distraction period and distraction speed. The changes were examined by means of bone biopsies and X-rays of the area at 0, 7, 14, 21, 45 and 55 days of the process. RESULTS: The most efficient osteogenic distraction parameters were a latency period of five days, a consolidation period of six weeks, distraction speed of 1 mm/day for distances of less than 20 mm, and 3 mm/day for longer distances. CONCLUSIONS: The sequential histological study allowed to observe the appearance of cellular elements (osteocytes, osteoclasts, osteoid matrix, trabeculate, etc.) and their participation in granulation tissue, newly-formed bone and compact mature bone.

ANTECEDENTES: Respecto a la distracción osteogénica (generación ósea inducida), con mayor o menor éxito han sido descritos diversos protocolos para el manejo del período de latencia, velocidad de distracción y período de consolidación. ­. OBJETIVO: Entender mejor el proceso de la distracción mandibular y establecer los factores determinantes y sus tiempos óptimos. MATERIAL Y MÉTODOS: Se estudiaron 27 perros sometidos a distracción osteogénica unidireccional, bilateral de la mandíbula. Los procesos de distracción se aplicaron con seis variantes, dos por cada factor (período de latencia, período de distracción y velocidad de distracción). Se estudiaron los cambios mediante biopsias del hueso y radiografías de la zona a los 0, 7, 14, 21, 45 y 55 días del proceso. RESULTADOS: Los parámetros de distracción osteogénica más eficientes fueron período de latencia de cinco días, período de consolidación de seis semanas, 1 mm diario de velocidad de distracción para distancias menores a 20 mm y 3 mm diarios para distancias mayores. CONCLUSIONES: El estudio histológico secuencial permitió observar la aparición de los elementos celulares (osteocitos, osteoclastos, matriz osteoide, trabeculado, etcétera) y su participación en el tejido de granulación, el hueso neoformado y el hueso maduro compacto.

Metatarsal lengthening by distraction osteogenesis for brachymetatarsia in paediatric patients: is it safe and effective?

PURPOSE: The primary aim is to assess the efficacy of the surgical callus distraction technique of the metatarsus in paediatric patients. Secondary objectives are to assess complications and treatment duration. We have also described the details of our surgical technique. MATERIALS AND METHODS: A case series review of paediatric patients who had metatarsal lengthening at our unit between 2014 and 2022. Patient demographics, duration of time in frame, complications and metatarsal length achieved were recorded. The AOFAS Midfoot and the MOXFQ were taken pre-operatively and at final follow-up. RESULTS: Sixteen metatarsals in 8 patients (14 feet) underwent lengthening between 2014 and 2022 using the MiniRail OrthoFix 100 (Orthofix Medical Inc, Lewisville, TX, USA). The mean age was 13.3 (12-17) years. The average duration between surgery and implant removal was 5.2 months. According to Paley's classification, there was one obstacle encountered in a patient who required a revision of their osteotomy and one problem in another patient who had an infected metatarsophalangeal joint stabilising k-wire treated with oral antibiotics. The Mean AOFAS Midfoot score improved from 53.10 to 86.40 (p < 0.0001) and the Mean MOXFQ improved from 32.5000 to 12.1250 (p < 0.05); these were statistically significant. CONCLUSION: Gradual metatarsal lengthening using the MiniRail external fixator is a safe and effective method to treat brachymetatarsia in paediatric patients. This preliminary report describes and supports metatarsal lengthening in appropriate patients. Holistic care in terms of a pre-operative assessment, psychological support and preparation for the extended rehabilitation period are vital.

[The use of magnetic therapy in the treatment of children with lower micrognathia using compression-distraction osteosynthesis]. / Primenenie magnitoterapii pri lechenii detei s nizhnei mikrognatiei metodom kompressionno-distraktsionnogo osteosinteza.

PURPOSE: To study the effect of magnetic therapy on the formation of distraction regenerate of the lower jaw in patients with lower micrognathia. MATERIALS AND METHODS: The study comprised 159 patients with inferior micrognathia of congenital and acquired etiology. The patients were divided into 2 groups. The main group consisted of 112 patients who received magnetic therapy: 55 patients with congenital micrognathia and 57 patients with acquired micrognathia. The control group included 47 patients who did not undergo magnetic therapy: 20 patients with congenital micrognathia and 27 patients with acquired micrognathia. Magnetic therapy was performed daily starting from day 1 or 2 after surgery. Ultrasound monitoring began on the 7th day of distraction and was carried out every 3-4 days, which made it possible to assess the dynamics of the formation of the distraction regenerate. RESULTS: Ultrasound examination on the 7th day of distraction revealed that in the main group the number of distraction regenerates of the normotrophic type was 36.5%, hypotrophic type 18%, hypertrophic type 54.5%. In the control group, the corresponding rates were 53%, 31% and 22%. CONCLUSION: Magnetic therapy induces osteogenesis and accelerates the maturation of the distraction regenerate. This makes it possible to accelerate the pace of distraction without reducing the quality of the regenerate.

The Role of Distraction Osteogenesis in Limb Salvage for Tumors.

Modern technology and advances in medicine have facilitated increasing rates of limb salvage in the treatment of sarcomas. Orthopedic oncologists have a wide array of reconstruction options for limb salvage, ranging from allografts to endoprosthesis reconstruction. Limb lengthening is another option available to an orthopedic oncologist faced with bony defects and limb length discrepancies following resection. This review provides a brief history of limb lengthening, the principles of distraction osteogenesis, and current applications in orthopedic oncology. Considering the complications and challenges associated with the lengthening process, appropriate patient selection and thorough patient counseling is key to optimizing outcomes.

Novel patient-specific helical maxillary distractor: an in vitro feasibility study.

At present, stock linear distractors are used for internal maxillary distraction osteogenesis. However, the authors' research group has demonstrated, through an in silico analysis, that linear distraction leads to bone deformities and malocclusion, whereas helical distraction can yield ideal outcomes. A system for designing and manufacturing custom helical distractors has recently been developed, and the feasibility of these appliances now needs to be assessed. This study was, therefore, conducted to gain an initial insight into their feasibility. The study had two goals. First, it aimed to demonstrate, in an in vitro model, that the novel system of custom helical distraction can produce appropriate clinical outcomes. The second aim was to compare the performance of custom helical distractors with that of stock devices and hybrid devices (i.e., linear appliances that feature patient-specific footplates). Interpreting the results as trends, this study showed that the system of custom helical distraction resulted in in vitro outcomes that were superior to those obtained with stock and hybrid devices.