Mechanical solutions to salvage failed distraction osteogenesis in large bone defect management. Int Orthop. 2019;43:1051-1059. [PMID: 29934717 DOI: 10.1007/s00264-018-4032-6]

Knowledge mapping and research trends of distraction osteogenesis in oral and maxillofacial surgery

BACKGROUND

Distraction osteogenesis (DO) has found extensive use in oral and maxillofacial surgery for correcting maxillofacial deformities due to its numerous advantages. However, comprehensive scientific and visual analyses of this field on a global scale are rare. Therefore, this study aims to provide a summary of the global trends and current status of DO in oral and maxillofacial surgery.

METHOD

Publications concerning DO in oral and maxillofacial surgery were comprehensively searched and selected from the Web of Science Core Collection(WOSCC) database. We evaluated the annual contributions from institutions, journals, countries, and authors using bibliometric analysis software.

RESULTS

A total of 541 publications were included in this study. The USA played a predominant role in this field, leading in both publication volume and international collaboration. Harvard University and the University of Hong Kong secured the top position in total publications, while the University of Texas System topped the list in total citations within this field. The Journal of Oral and Maxillofacial Surgery emerged as the primary contributing journal, and Cheung LX emerged as the primary contributing author in the field of distraction osteogenesis (DO) in oral and maxillofacial surgery. Keywords such as 'orthognathic surgery,' 'reconstruction,' and 'osteogenesis' are anticipated to be prominent topics in future research.

CONCLUSION

Between 1995 and 2023, there has been rapid growth in the total number of publications within the field of distraction osteogenesis (DO) in oral and maxillofacial surgery. The USA stands out as the predominant country in this field. Surgeries, orthognathic surgery, and osteogenesis have emerged as prominent topics. The findings of our study offer valuable insights for scholars seeking to identify research hotspots and chart the developmental direction of DO in oral and maxillofacial surgery.

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 0.5 mm/day for 10 days, following a latency period of 5 days. 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 6 weeks 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 6 weeks 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 4 weeks 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.

Limb salvage and functional recovery in infected nonunion of the distal tibia treated with the Ilizarov techniques

Introduction

Treatment of infected nonunion of the distal juxta-articular tibia is a challenge due to a short distal fragment, deformity, thin soft-tissue envelope, and active infection. There is still no consensus on the approach that is able to maximally salvage the limb and ankle function.

Material and methods

Infected juxta-articular nonunion of the distal tibia was managed with two Ilizarov techniques, monofocal compression (MC) used in 12 patients and bifocal compression-distraction (BCD) in 6 patients. The choice of the technique depended on the size of the postresection defect, ≥3 cm or ≤3 cm, respectively. The tactics of functional approach were careful debridement, insertion of wires in the distal fragment so that they do not penetrate the ankle joint, stable fixation, and temporary bridging of the ankle and forefoot. MSCT was used along with regular radiography to assess the union and regeneration. Ankle functions were evaluated with AOFAS ankle-hindfoot score system.

Results

Bone consolidation, infection arrest and ankle function improvement were achieved in all patients. External fixation continued 221.7 ± 15.1 days for MC and 235 ± 25.8 days for BCD. Complications were wound divergence, wire-tract infection, premature consolidation of the fibula, and hypoplastic regeneration in one case. The mean functional AOFAS score after treatment was 90.7 ± 2.5 points in MC and 89.7 ± 1.3 in BCD patients. Residual limb discrepancy after MC ranged 0-4 cm. Bone shortening was compensated in BCD patients.

Conclusion

Limb-salvage and functional approach to the treatment of infected nonunion of the juxta-articular distal tibia with the Ilizarov techniques achieves good outcomes. It provides bone infection arrest, consolidation, defect compensation and significantly improves the ankle joint function.

Rat bone marrow mesenchymal stem cells induced by rrPDGF-BB promotes bone regeneration during distraction osteogenesis

Background: In the clinical treatment of large bone defects, distraction osteogenesis can be used. However, some patients may suffer from poor bone regeneration, or even delayed healing or non-union. Problems with the aggregation and proliferation of primary osteoblasts, or problems with the differentiation of primary osteoblasts will lead to poor bone regeneration. Therefore, supplementing exogenous primary osteoblasts and growth factors when using distraction osteogenesis may be a treatment plan with great potential. Methods: Bone marrow mesenchymal stem cells (BMSCs) were extracted from rats and cultured. Subsequently, Recombinant Rat Platelet-derived Growth Factor BB (rrPDGF-BB) was used to induce bone marrow mesenchymal stem cells. At the same time, male adult rats were selected to make the right femoral distraction osteogenesis model. During the mineralization period, phosphate buffer salt solution (control group), non-induction bone marrow mesenchymal stem cells (group 1) and recombinant rat platelet-derived growth factor BB intervened bone marrow mesenchymal stem cells (group 2) were injected into the distraction areas of each group. Then, the experimental results were evaluated with imaging and histology. Statistical analysis of the data showed that the difference was statistically significant if p < 0.05. Results: After intervention with recombinant rat platelet-derived growth factor BB on bone marrow mesenchymal stem cells, the cell morphology changed into a thin strip. After the cells were injected in the mineralization period, the samples showed that the callus in group 2 had greater hardness and the color close to the normal bone tissue; X-ray examination showed that there were more new callus in the distraction space of group 2; Micro-CT examination showed that there were more new bone tissues in group 2; Micro-CT data at week eight showed that the tissue volume, bone volume, percent bone volume, bone trabecular thickness, bone trabecular number and bone mineral density in group 2 were the largest, and the bone trabecular separation in group 2 was the smallest. There was a statistical difference between the groups (p < 0.05); HE staining confirmed that group 2 formed more blood vessels and chondrocytes earlier than the control group. At 8 weeks, the bone marrow cavity of group 2 was obvious, and some of them had been fused. Conclusion: The study confirmed that injecting bone marrow mesenchymal stem cellsBB into the distraction space of rats can promote the formation of new bone in the distraction area and promote the healing of distraction osteogenesis.

Mesenchymal Stem Cells–Hydrogel Microspheres System for Bone Regeneration in Calvarial Defects

The repair of large bone defects in clinic is a challenge and urgently needs to be solved. Tissue engineering is a promising therapeutic strategy for bone defect repair. In this study, hydrogel microspheres (HMs) were fabricated to act as carriers for bone marrow mesenchymal stem cells (BMSCs) to adhere and proliferate. The HMs were produced by a microfluidic system based on light-induced gelatin of gelatin methacrylate (GelMA). The HMs were demonstrated to be biocompatible and non-cytotoxic to stem cells. More importantly, the HMs promoted the osteogenic differentiation of stem cells. In vivo, the ability of bone regeneration was studied by way of implanting a BMSC/HM system in the cranial defect of rats for 8 weeks. The results confirmed that the BMSC/HM system can induce superior bone regeneration compared with both the HMs alone group and the untreated control group. This study provides a simple and effective research idea for bone defect repair, and the subsequent optimization study of HMs will provide a carrier material with application prospects for tissue engineering in the future.

Efficacy comparison of trifocal bone transport using unilateral external fixator for femoral and tibial bone defects caused by infection

BACKGROUND

This study aimed to evaluate the clinical and functional outcomes of patients with femoral and tibial critical-sized bone defect (CSBD) treated by trifocal bone transport using the Ilizarov method.

METHODS

From March 2011 and January 2017, clinical and radiographic data of patients with CSBD (> 6 cm) caused by infection were documented and analyzed. Patients were divided into the femur group (n = 18) and tibia groups (n = 21) according to the location of bone transport. The bone and functional outcomes were evaluated according to the Association for the Study and Application of the Method of the Ilizarov (ASAMI) criterion, and postoperative complications were evaluated by Paley classification.

RESULTS

A total of 39 patients were managed by the trifocal bone transport for the femur (n = 18) or tibia (n = 21) bone defects with a mean follow-up time of 26.1 months (range 17-34 months). Eighteen femurs and 21 tibias with a mean distraction regenerate length (DRL) of 8.3 cm (range 6-13 cm) and 7.5 cm (range 6-11 cm) respectively. Infection was eradicated in all patients, and the total bone union was received in all cases (100%). Statistical difference of bone grade (excellent/good/fair/poor, 3/11/3/1 vs 2/13/4/2, P < 0.05), and function grade (excellent/good/fair/poor, 3/14/1/0 vs 4/13/3/1, P < 0.05) were respectively observed between the femur group and tibia group. The excellent and good rate of bone (femur vs tibia, 77.8% vs 71.4%), and function grade (femur vs tibia, 94.4% vs 80.9%) was higher in the femur group than the tibia. The rate of complication in the femur group was lower than in the tibia (femur vs tibia, 94.4% vs 76.2%). One femur and five tibias were performed additional surgery for delayed union and axial deviation.

CONCLUSIONS

The trifocal bone transport using the unilateral external fixator was a practical method in the management of CSBD in the lower extremity. The BUT and EFI of the femur group were shorter than the tibia. Although the complications noted were more frequent on the femur, these were mostly minor.

Evaluation of complications associated with bifocal bone transport as treatment for either proximal, intermediate or distal femoral defects caused by infection: outcome analysis of 76 patients

Background

The purpose of this study was to evaluate the outcomes of bifocal bone transport in the treatment of femoral bone defects caused by infections.

Methods

Clinical and radiographic data of patients with infected femoral nonunion treated by the bifocal bone transport at our hospital were analyzed retrospectively, from January 2008 to December 2019. Depending on the location of bone defects, the patients were divided into three groups (proximal, intermediate, and distal). The Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria was applied to assess the bone and functional outcomes. Postoperative complications of three groups were documented and compared.

Results

Seventy-six cases of infected femoral bone defects (31 cases of proximal, 19 cases of intermediate, and 26 cases of distal) were managed by bifocal bone transport successfully with a mean follow-up time of 30.8 months (range, 23 to 41 months). There were 58 men (76.3%) and 18 women (23.6%), with a mean age of 38.8 years (range, 23 to 60 years). The bone union was received in 76 cases with a mean of 6.9 months (range, 5 to 8 months). Pin tract infection was observed in twenty-nine cases (38.1%), 7 cases (9.2%) of muscle contractures, 3 cases (7.9%) of joint stiffness, 13 cases (17.1%) of axial deviation, 2 cases (2.6%) of delayed union, one case (1.3%) of nonunion, and none (0%) of transport gap re-fracture. One patient (1.3%) was scheduled for knee arthroplasty when bone transport treatment ended.

Conclusions

Bone transport using an external rail fixator was a practical method to treat the femoral bone defects, since the satisfactory rate of bone union and limb function recovery. Complications of distal femoral bone transport were more severe than the proximal and intermedia, but the rate of complication was the least of the three groups. Soft-tissue-related complications were more likely to occur in the intermediate bone transport.

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research (dedicated to 100th birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed “limb lengthening and reconstruction surgery”. Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal’s rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.

Management of segmental bone defects of the upper limb: a scoping review with data synthesis to inform decision making

PURPOSE

Injuries to the long bones of the upper limb resulting in bone defects are rare but potentially devastating. Literature on the management of these injuries is limited to case reports and small case series. The aim of this study was to collate the most recent published work on the management of upper limb bone defects to assist with evidence based management when confronted with these cases.

METHODS

Following a preliminary search that confirmed the paucity of literature and lack of comparative trials, a scoping review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) was conducted. A literature search of major electronic databases was conducted to identify journal articles relating to the management of upper limb long bone defects published between 2010 and 2020.

RESULTS

A total of 46 publications reporting on the management of 341 patients were reviewed. Structural autograft, bone transport, one-bone forearm and the induced membrane technique were employed in an almost equal number of cases. The implemented strategies showed similar outcomes but different indications and complication profiles were observed.

CONCLUSION

Contemporary techniques for the management of post-traumatic upper limb bone defects all produce good results. Specific advantages, disadvantages and complications for each modality should be considered when deciding on which management strategy to employ for each specific patient, anatomical location, and defect size.

Treatment of diaphyseal forearm defects caused by infection using Ilizarov segmental bone transport technique

Background

The Ilizarov segmental bone transport technique can be applied in the reconstruction of the bone defects with less invasive fashion and more versatility compared to other methods, while most studies were focused on the lower extremity. The purpose of this study was to evaluate the effectiveness of the Ilizarov segmental bone transport technique in the treatment of diaphyseal forearm bone defects caused by infection.

Methods

This study included 12 patients with diaphyseal forearm bone defects caused by infection, who underwent bone transport procedures using the monolateral external fixator at our institution from January 2010 to January 2018, including 10 males and 2 females with a mean age of 39 years (range 23–57 years). Patient’s demographic data and clinical outcomes at least two years follow-up after removing the external fixator were collected and retrospectively analyzed. The functional results were evaluated by the questionnaire of Disability of Arm, Shoulder and Hand (DASH) and the modified Mayo wrist score (MWS) at the final follow-up.

Results

There were 10 radii and 2 ulnae bone transport procedures collected. The average defect size was 5.1 cm (4-6.5 cm). All patients were successfully followed up with a mean period of 28.2 months (24 to 36 months) and achieved infection-free union. There was no recurrence of infection observed. The mean external fixation time was 232.6 days (182 to 276 days), and the mean external fixation index was 46.3 days/cm (40.9 to 61.8 days/cm). The mean DASH score was 30.6(18 to 49) preoperative, while 13.8 (5 to 26) at the final follow-up. The average modified MWS improved from 68.8 (55 to 80) pre-operatively to 83.8 (65 to 90) at the final follow-up. All the differences between the preoperative and final scores were statistically significant (p < 0.05). Almost all the patients achieved satisfactory clinical outcomes and were able to perform activities of daily living.

Conclusions

Ilizarov segmental bone transport technique is an alternative and effective method for the treatment of diaphyseal forearm bone defects caused by infection, and this method acquired satisfactory clinical outcomes.

Interleukin-4-loaded hydrogel scaffold regulates macrophages polarization to promote bone mesenchymal stem cells osteogenic differentiation via TGF-β1/Smad pathway for repair of bone defect

Objective

Tissue engineering is a promising strategy for repair of large bone defect. However, the immune system reactions to biological scaffold are increasingly being recognized as a crucial factor influencing regeneration efficacy. In this study, a bone‐bioactive hydrogel bead loaded with interleukin‐4 (IL‐4) was used to regulate macrophages polarization and accelerate bone regeneration.

Methods

IL‐4‐loaded calcium‐enriched gellan gum (Ca‐GG + IL‐4) hydrogel beads were synthesised. And the effect on cell behaviour was detected. Furthermore, the effect of the Ca‐GG + IL‐4 hydrogel bead on macrophage polarization and the effect of macrophage polarization on bone mesenchymal stem cells (BMSCs) apoptosis and osteogenic differentiation were evaluated in vitro and in vivo.

Results

BMSCs were able to survive in the hydrogel regardless of whether IL‐4 was incorporated. Immunofluorescence staining and qPCR results revealed that Ca‐GG + IL‐4 hydrogel bead could promote M2 macrophage polarization and increase transforming growth factor (TGF)‐β1 expression level, which activates the TGF‐β1/Smad signalling pathway in BMSCs and promotes osteogenic differentiation. Moreover, immunohistochemical analysis demonstrated Ca‐GG + IL‐4 hydrogel bead could promote M2 macrophage polarization and reduce cell apoptosis in vivo. In addition, micro‐CT and immunohistochemical analysis at 12 weeks post‐surgery showed that Ca‐GG + IL‐4 hydrogel bead could achieve superior bone defect repair efficacy in vivo.

Conclusions

The Ca‐GG + IL‐4 hydrogel bead effectively promoted bone defect regeneration via regulating macrophage polarization, reducing cell apoptosis and promoting BMSCs osteogenesis through TGF‐β1/Smad pathway. Therefore, it is a promising strategy for repair of bone defect.

Role of the Ilizarov non-free bone plasty in the management of long bone defects and nonunion: Problems solved and unsolved

BACKGROUND

Ilizarov non-free bone plasty is a method of distraction osteogenesis using the Ilizarov apparatus for external fixation which originated in Russia and was disseminated across the world. It has been used in long bone defect and nonunion management along with free vascularized grafting and induced membrane technique. However, the shortcomings and problems of these methods still remain the issues which restrict their overall use.

AIM

To study the recent available literature on the role of Ilizarov non-free bone plasty in long bone defect and nonunion management, its problems and the solutions to these problems in order to achieve better treatment outcomes.

METHODS

Three databases (PubMed, Scopus, and Web of Science) were searched for literature sources on distraction osteogenesis, free vascularized grafting and induced membrane technique used in long bone defect and nonunion treatment within a five-year period (2015-2019). Full-text clinical articles in the English language were selected for analysis only if they contained treatment results, complications and described large patient samples (not less than ten cases for congenital, post-tumor resection cases or rare conditions, and more than 20 cases for the rest). Case reports were excluded.

RESULTS

Fifty full-text articles and reviews on distraction osteogenesis were chosen. Thirty-five clinical studies containing large series of patients treated with this method and problems with its outcome were analyzed. It was found that distraction osteogenesis techniques provide treatment for segmental bone defects and nonunion of the lower extremity in many clinical situations, especially in complex problems. The Ilizarov techniques treat the triad of problems simultaneously (bone loss, soft-tissue loss and infection). Management of tibial defects mostly utilizes the Ilizarov circular fixator. Monolateral fixators are preferable in the femur. The use of a ring fixator is recommended in patients with an infected tibial bone gap of more than 6 cm. High rates of successful treatment were reported by the authors that ranged from 77% to 100% and depended on the pathology and the type of Ilizarov technique used. Hybrid fixation and autogenous grafting are the most applicable solutions to avoid after-frame regenerate fracture or deformity and docking site nonunion.

CONCLUSION

The role of Ilizarov non-free bone plasty has not lost its significance in the treatment of segmental bone defects despite the shortcomings and treatment problems encountered.