Congenital Pseudarthrosis Of Tibia Research Articles

Guided Growth to Treat Anterolateral Tibial Bowing Associated with Congenital Pseudarthrosis of the Tibia.

Anterolateral tibial bowing associated with congenital tibial pseudarthrosis occurs often in patients with neurofibromatosis type 1 and results from the inability of the fractured bone to unite, leading to persistent nonunion, abnormal bone growth, and further bowing of the tibia. Current surgical and nonsurgical approaches demonstrate persistent nonunion or refracture, often resulting in amputation. This report describes the management of 3 patients with anterolateral tibial bowing and NF1 who underwent distal tibia-guided growth. The patients had an average age of 1.6 years at initial operation, with a total of 3 to 4 surgeries over an average of 2.1 years. The latest follow-up on all patients is included, at a mean of 5.1 years after the initial operation. All 3 patients experienced substantial functional improvement and improved alignment of the mechanical axis of the tibia. One patient has experienced refracture. Our study indicates that guided growth can serve as an additional surgical option to improve ALTB and potentially reduce the risk of fracture and pseudarthrosis by restoring normal mechanical alignment. Level-IV, Case Series.

Treatment of Congenital Pseudarthrosis Tibia by Ilizarov Principle

Treatment of Congenital Pseudarthrosis Tibia by Ilizarov Principle

Comparison of two different intramedullary rods combined with Ilizarov external fixation and wrapped autologous iliac bone grafting for the treatment of congenital tibial pseudarthrosis in children

Objective: To compare the initial clinical efficacy of extensible intramedullary rod fixation and Williams intramedullary rod fixation combined with Ilizarov external fixation and wrapped autologous iliac bone grafting in the treatment of congenital tibial pseudarthrosis in children. Methods: A retrospective analysis was conducted on the clinical data of 60 children with Crawford Ⅳtype congenital pseudarthrosis of the tibia treated with combined surgery at the Orthopedics Department of Hunan Children's Hospital from January 2013 to December 2020.According to different internal fixation methods,patients were divided into the extensible intramedullary rod group (30 cases) and the Williams intramedullary rod group (30 cases). There were 12 males and 18 females in the extendable intramedullary rod group, aged (33.6±6.3) months (range: 18 to 44 months), while there were 10 males and 20 females in the Williams intramedullary rod group, aged (47.8±8.6) months (range: 36 to 66 months). The anteroposterior and lateral views of tibia and fibula and the full length anteroposterior film of both lower limbs were examined to compare the clinical treatment effects of the two groups at 1-,3-,6-,9-, and 12-month after surgery. Independent sample t-test, χ2 test or Fisher exact test was used for inter group comparison. Results: Both groups of children underwent surgery successfully, with postoperative follow-up time greater than 2 years. The extensible intramedullary rod group was followed up for (49.5±6.4) months, while the Williams intramedullary rod group was followed up for (53.7±10.5) months. The initial bone healing time between the broken ends of the tibial pseudarthrosis was (5.1±0.8) months in the extensible intramedullary rod group and (5.0±0.6) months in the Williams intramedullary rod group. There was no statistically significant difference between the two groups (t=0.584, P=0.562). The initial postoperative bone healing rate of the extensible intramedullary rod group was 93.3% (28/30), while that of the Williams intramedullary rod group was 96.7% (29/30). There was no statistically significant difference between the groups (χ2=0.351 P=0.554).The postoperative fracture rate of the extensible intramedullary rod group was 20.0% (6/30), while that of the Williams intramedullary rod group was 16.7% (5/30);Six cases (20.0%) in the extensible intramedullary rod group had unequal limb lengths in both lower limbs after surgery, with a limb length difference of (2.5±1.4)cm (range: 1.5 to 5.2 cm). Eight cases (26.7%) in the Williams intramedullary rod group had a limb length difference of (2.8±1.4)cm (range: 1.8 to 6.0 cm);After surgery, there were 4 (13.3%) cases of proximal tibial valgus deformity in the extensible intramedullary rod group, with an valgus angle range of (12.5±4.9)° (range: 7 °to 18°), and 3 (10.0%) cases in the Williams intramedullary rod group, with an valgus angle of (15.0±6.0)° (range: 9°to 21°). There were 2 (6.7%) cases of ankle valgus deformity in the extensible intramedullary rod group, with an valgus angle of (11.5±4.9)° (range: 8 °to 15°), and 4 (13.3%) cases in the Williams intramedullary rod group, with an valgus angle of (14.8±6.2)° (range: 6 °to 20°). The postoperative activities of the knee and ankle joints in the extensible intramedullary rod group were normal and unrestricted, with 4 cases of extensible intramedullary rod displacement.In the Williams intramedullary rod group, there were 30 cases of postoperative ankle joint stiffness and no displacement of the fixation position of the intramedullary rod.There was no statistically significant difference in postoperative complications between the two groups of children (all P>0.05). Conclusions: The use of both extensible intramedullary rods and Williams intramedullary rods in the combined surgery for congenital tibial pseudarthrosis in children can achieve effective internal fixation results. The initial postoperative bone healing rate is high, and there is no difference in the incidence of postoperative complications between groups. Both internal fixation methods have their own advantages and disadvantages, and suitable internal fixation methods can be selected based on the characteristics of the patient.

Outcomes of Four in One Osteosynthesis in the treatment of Congenital Tibial Pseudarthrosis: A Systematic Review

Background CPT has a natural history of recalcitrant nonunion, bone atrophy, progressive LLD and deformity, and persistent refracture even after surgical union. Aim of the Work The aim of treatment for CPT is to achieve and sustain union. Methodology Studies were considered eligible if the authors described the surgical procedure of tibial pseudarthrosis, patient‘s clinical and/or functional outcomes were reported, any complications intraoperatively and post-operatively were reported, the full- text articles were available, and the articles were written in English. The MED-LINE database, PubMed, science direct, Cochrane Register of Controlled Trails (The Cochrane Library), and Google Scholar were searched upon using the following keyword: congenital tibial pseudarthrosis, CPT, tibiofibular fusion, tibiofibular osteosynthesis, four in one osteosynthesis, tibia and fibula one mass fusion, Paley x method, and cross union. Results The cumulative data extracted provided 96 patients in 6 papers of which 60% were male and the other 40 % were females. The mean age was around 4.1 Years ranging from the first year till nearly eleven years old and the mean follow up was around 4.1 Years. The percentage of patient with neurofibromatosis type 1 was 53.13 % and 41.1 % had previous surgical intervention. All studies have mentioned that cross sectional area of healing mass increased and the relative crosssectional area was large in comparison to proximal shaft or proximal metaphysis. Unfortunately, no single method of assessing the cross-sectional area and relative cross-sectional area were used by different authors. Conclusion According to the findings of our research, cross sectional area is the most important factor in preventing refracture. New technology and therapeutics will emerge as new pharmacologic therapeutics and a deeper understanding of this disease emerge. Meanwhile, the best current combination treatment for CPT is hamartoma resection, periosteal grafting, bone grafting, Cross union, internal rodding, external fixation, tibiofibular Cross union, BMP, and bisphosphonate.

Long term follow-up evaluation of combined surgery for congenital tibial pseudarthrosis in children

Objective: To explore the long-term effect of combined surgery for the treatment of congenital tibial pseudarthrosis in children. Methods: The clinical data of 44 children with congenital tibial pseudarthrosis who underwent combined surgery (tibial pseudarthrosis tissue resection, intramedullary rod fixation, Ilizarov external fixator fixation, wrapped autologous iliac bone graft) from August 2007 to October 2011 at the Department of Pediatric Orthopedics, Hunan Children's Hospital were collected retrospectively. There were 33 males and 11 females. The age at the time of surgery was (3.7±2.2)years (range:0.6 to 12.4 years), including 25 cases under 3 years old and 19 cases above 3 years old.Among them, 37 cases were complicated with neurofibromatosis type 1.The operation status, postoperative complications and follow-up results were recorded. Results: The follow-up time after surgery was (10.9±0.7)years (range:10 to 11 years).Thirty-nine out of 44 patients (88.6%) achieved initial healing of tibial pseudarthrosis, with an average healing time of (4.3±1.1)months (range:3 to 10months).In the last follow-up, 36 cases (81.8%) had unequal tibial length, 20 cases (45.4%) had refractures, 18 cases (40.9%) had ankle valgus, 9 cases (20.4%) had proximal tibial valgus, and 11 cases (25.0%) had high arched feet.Nine cases (20.4%) developed distal tibial epiphyseal plate bridging.17 cases (38.6%) had abnormal tibial mechanical axis.Seven cases (15.9%) developed needle infection, and one case (2.3%) developed tibial osteomyelitis. 21 patients (47.7%) had excessive growth of the affected femur.Five patients (11.3%) had ankle stiffness, and 34 patients (77.2%) had intramedullary rod displacement that was not in the center of the tibial medullary cavity.Among them, 8 cases (18.1%) protruded the tibial bone cortex and underwent intramedullary rod removal.18 children have reached skeletal maturity, while 26 children have not been followed up until skeletal maturity. Conclusion: Combined surgery for the treatment of congenital pseudarthrosis of the tibia in children has a high initial healing rate, but complications such as unequal tibia length, refracture, and ankle valgus occur during long-term follow-up, requiring multiple surgical treatments.

Clinical study of a new type of telescopic rod for the treatment of congenital pseudarthrosis of the tibia in children.

The purpose of this study was to investigate the initial efficacy of a new telescopic rod in the treatment of congenital pseudarthrosis of tibia (CPT) in children. A new type of telescopic rod for children was designed and its clinical results were evaluated. There were nine cases of CPT on the right and six cases on the left; there were six females and nine males. The average age at operation was 35.5 months. There were 12 cases with neurofibromatosis type 1 and 4 cases with proximal tibial dysplasia. The initial healing of tibial pseudarthrosis, proximal tibial valgus deformity, tibial length, ankle valgus, ankle function, and intramedullary rod displacement were evaluated during follow-up. All 15 cases were followed up for an average of 18.2 months, 14 cases achieved initial healing, with an average healing time of 4.3 months. Ten cases had unequal lengths of the tibia, with an average of 0.9 cm. Proximal tibial valgus occurred in seven cases and ankle valgus occurred in one child. The average range of motion of the ankle joint was 23° and the average plantar flexion was 42°. The average extension of the new telescopic rod was 1.6 cm. The displacement of the telescopic rod occurred in seven cases, there was no epiphyseal plate tethering and re-fracture. The new children's telescopic rod has a reasonable design and can extend with the growth of tibia. There are no complications of epiphyseal plate tethering and re-fracture. It provides a new choice of intramedullary fixation for the treatment of CPT.

New insights into pathogenesis of congenital pseudarthrosis of tibia in children using periosteum proteomics analysis.

The exact etiology and pathogenesis of congenital pseudarthrosis of tibia (CPT) are not clear. Quantitative proteomics analysis plays a vital role in disease pathology research. Tandem mass tag (TMT)-based proteomics techniques were employed to identify and analyze the differentially expressed proteins (DEP) in the tibia periosteum tissues of CPT patients. The samples were divided into three groups: CPT with NF1 group, CPT without NF1 group (non-NF1-CPT), and control group (patients with open tibial fracture). A fold change ≥1.5 or ≤0.66 and P-value <0.05 were used as the thresholds to screen DEPs. Subsequently, bioinformatics resources such as online tools DAVID and String were used to generate gene ontology (GO) annotation, KEGG pathways enrichment, and protein-protein interaction (PPI) network for these DEPs. The results show that a total of 347 proteins were differentially expressed in NF1-CPT groups, 212 of which were upregulated and 135 were downregulated. There were more DEPs in non-NF1-CPT groups; we identified 467 DEPs, including 281 upregulated and 186 downregulated. Among them, NF1-CPT groups and non-NF1-CPT groups shared 231 DEPs, and the remaining 230 DEPs showed the same expression trend in the two disease groups, with 117 upregulated and 113 downregulated. In particular, 116 proteins were altered only in NF1-CPT groups (94 were upregulated and 22 were downregulated), whereas 236 proteins were altered only in non-NF1-CPT groups (164 were upregulated and 72 were downregulated). Finally, compared with non-NF1-CPT groups, 47 proteins changed 1.5-fold and P-value < 0.05 in NF1-CPT groups. To sum up, we found that common DEPS in periosteum of NF1-CPT and non-NF1-CPT groups are mainly involved in cell matrix assembly, cell adhesion, AKT-PI3K signal pathway activation, and vascular agglutination, which indicate that these are the pathological characteristics of CPT. The osteogenic ability is weak, the osteoclastic ability is strong, the vascular lumen is narrow, the invasive growth and the proliferation of fibroblasts are enhanced in CPT patients.

Analysis of related factors of behavioral problems in children with congenital pseudarthrosis of tibia.

SUMMARYOBJECTIVE:This study aimed to investigate the factors associated with behavioral problems in children with congenital pseudarthrosis of the tibia.METHODS:Random sampling is utilized to obtain a sample of 90 patients. The behavioral problems of the patients are detected by Achenbach Children's Behavior Scale. Parental emotional problems are investigated by the Self-Rating Depression Scale and Self-Rating Anxiety Scale.RESULTS:The results demonstrate that the detection rate of behavioral problems in children with congenital pseudarthrosis of the tibia is 53.3% (48/90). Among these behavioral problems, an abnormal rate is higher in the four dimensions: thinking, violation of discipline, social interaction, and aggression. The anxiety and depression scores of caregivers are statistically higher in the abnormal group than in the normal group. The results of the multivariate analysis show that the anxiety degree of the parents had a significant impact on the behavior of the children.CONCLUSIONS:Children with congenital pseudarthrosis of the tibia are facing the issues of high rates of behavioral problems. Parents of children with congenital pseudarthrosis of the tibia had higher levels of anxiety and depression than parents of normal children. The anxiety and depressive state of mind of parents or caregivers had a significant impact on the behavior of children with congenital pseudarthrosis of the tibia.

Efficacy Comparison of 3 Kinds of Distal Tibial Hemiepiphyseal Implants in the Treatment of Postoperative Ankle Valgus of Congenital Pseudarthrosis of the Tibia.

Congenital pseudarthrosis of the tibia (CPT) is a complex and serious disease in orthopaedics which often requires multiple operations for treatment. Postoperative ankle valgus deformity is easily seen after the operation of CPT. The aim of this study is to retrospectively evaluate the effectiveness of three different implants for treating postoperative ankle valgus after CPT. A total of 41 patients with postoperative ankle valgus after CPT from December 2010 to July 2019 were selected. Of these 41 patients, 23 patients were treated with "U"-shaped staple, 10 patients were treated with hollow screw and 8 patients were treated with cortical bone screw. The evaluation index was tibiotalar angle. The general data, preoperative, postoperative, and final follow-up imaging data were recorded, and the deformity correction rate and complications were compared. All the patients were performed with postoperative follow-up visit for at least 12 months (31 mo on average). In the "U"-shaped staple group, the preoperative tibiotalar angle was 74.8±4.8 degrees, the tibiotalar angle was 85.8±4.5 degrees when the internal fixation was removed; in the hollow screw group, the average preoperative tibiotalar angle was 72.2±6.1 degrees, the average tibiotalar angle was 88.4±5.1 degrees when the internal fixation was removed; in the cortical bone screw group, the average preoperative tibiotalar angle was 75.1±4.2 degrees, the average tibiotalar angle was 88.4±5.1 degrees when the internal fixation was removed. The correction rate of the "U"-shaped staple group was 0.71 degrees/month, with that of in the hollow screw group and cortical bone screw group being 0.64 degrees/month and 0.61 degrees/month, respectively. There was no significant difference in the correction rate between the 3 groups. One case of internal fixation complication was reported in the hollow screw group; 2 cases of missing correction effect were reported, 1 in cortical bone screw group and 1 in hollow screw group; and 2 cases showing symptom of wound pain were reported in the "U"-shaped staple group. Ankle valgus is a common postoperative complication of congenital tibial pseudarthrosis. Temporary hemiepiphysiodesis with "U"-shaped staple or screws is an effective treatment for postoperative ankle valgus deformity of CPT in children. Level IV-retrospective study.

Surgical treatment options for congenital pseudarthrosis of tibia in children: cross-union versus other options: a systematic review.

The systematic review aimed to provide a comprehensive update on various surgical treatment options for congenital pseudarthrosis of tibia (CPT) in children and the outcome achieved in terms of union, union time and complications of non-union and refracture. A literature search was performed in PubMed (including Medline) database for broad keywords: 'Congenital pseudarthrosis of tibia and children'. Studies selected included full-text articles on surgical treatments of CPT following: intra-medullary rod (IMR)/Ilizarov/combined IMR with Ilizarov/vascularized fibular graft (VFG) and cross-union. Out of 719 studies, 57(1227 CPT patients/1235 tibias) were included for review. Cross-union group had 100% union rate with no non-unions, least refracture rate (22.5%) and minimal time to primary union (4.5 months). For IMR, Ilizarov, combined IMR with Ilizarov and VFG, the respective results were as follows: primary union rates - 67.7, 84.2, 83.7 and 65.3%; final union - 76.5, 81.5, 92.4 and 87.1%; primary union time - 12.6, 9.3, 5.3 and 9.5 months; non-union rates - 17.0, 13.6, 6.0 and 7.9%; refracture rates - 48.1, 47.7, 33.7 and 34.6%. The success probability was lowest for IMR (35.2%), 44% for Ilizarov, 55.5% for combined IMR with Ilizarov, 42.7% for VFG and highest 77.5% for cross-union group. Outcomes of the more recent cross-union technique fare better than other surgical methods. However, studies on cross-union are few and longer follow-up is lacking. Combined IMR with Ilizarov and VFG have better results compared to IMR or Ilizarov alone.

Free Vascularized Fibular Graft for Congenital Pseudarthrosis Tibia: A Case Series

Introduction: Congenital pseudarthrosis tibia (CPT) probably one of the most difficult to treat among all diseases in the children. There are several surgical approaches that have been used to treat CPT including on-lay graft, double on-lay grafts, pedicle grafts, osteotomy, bypass graft and intramedullary rods. Prognosis of CPT has changed considerably with the use of Free Vascularized Fibular Graft (FVFG). Despite these advances, several operations are often necessary to obtain union of CPT and the risk of amputation is never entirely eliminated Case presentation: We presented 2 case with CPT. The first case is a 4 year old girl with CPT-Associated Neurofibromatosis, patient was brought to orthopedic polyclinic complaining bend on her right leg since she was born, the parent also complained her child has abnormality when walking since she was 14 months old. The second case is a 3 year old girl with CPT complaining bend on her right leg, abnormalities and pain when walking since she was aged 1 years 11 months. We performed free vascularized fibular graft for both of the patient. Result: The results in our cases showed bone union in 14 weeks, 16 weeks and 18 weeks respectively. The optimal of technique options should be adapted to the type of pseudarthrosis and especially to the extent of the bone defects. good results can be found with intramedullary nailing with a bone graft or the Ilizarov technique Conclusion: The optimal of technique options should be adapted to the type of pseudarthrosis and especially to the extent of the bone defects Keywords: Congenital pseudarthrosis tibia, Free vascularized fibular graft, case series.

Effect of lengthening speed on the quality of callus and complications in patients with congenital pseudarthrosis of tibia.

This study aims to evaluate the effect of lengthening speed on the quality of callus and complications during distraction osteogenesis and describe an optimal lengthening speed in patients with congenital pseudarthrosis of tibia (CPT). Twenty-seven patients with CPT with a minimum follow-up of 36 months who underwent limb lengthening surgery between 1997 and 2016 with external fixator only were included in this study. All patients underwent lengthening procedures after achieving complete bone union in this study. Regenerate quality is evaluated according to the Li classification on the X-ray taken onemonth after the end of the distraction period. Complications were noted in post-operative follow-up period. Receiver operator characteristics (ROC) curve analysis was performed to obtain optimal lengthening speed for these patients. The mean age at the time of surgery was 5.74 years. The mean lengthening speed was 0.596 mm/day. Follow-up period of 136.14 months with a mean lengthening period of 92.4 days. Mean amount of lengthening was 5.44 cm for patients with CPT. Total rate of callus with good morphological quality was calculated as 66%. According to ROC analysis, optimal cut-off values of lengthening speed for the obtaining good morphological quality callus was 0.564 mm/day for tibial lengthening in CPT. There was a significantly positive correlation between complication rate and lengthening speed for each group. We recommend a mean lengthening rate of 0.56mm/day for the lengthening procedures with external fixator in patients with CPT who had complete bone union at the area of pseudarthrosis.

Serum-derived exosomes from neurofibromatosis type 1 congenital tibial pseudarthrosis impaired bone by promoting osteoclastogenesis and inhibiting osteogenesis.

Treatment of congenital pseudarthrosis of the tibia (CPT) still is full of challenges in pediatric orthopedist. Serum-derived exosomes (SDEs) have been proven to be participated in bone remodeling. However, the molecular changes in SDEs of CPT children and their pathologies have not been elucidated. In this study, SDEs were isolated and purified from CPT patients (CPT-SDEs) associated with neurofibromatosis type 1 (NF1) and normal children (Norm-SDEs). Then we obtained the proteomics profile of SDEs by combining liquid chromatography-tandem mass spectrometry (LC-MS/MS) and tandem mass tag label-based quantitation. In vitro, the efficacy of SDEs on osteoblastic differentiation of MC3T3-E1 cells and osteoclastogenesis ability of RAW264.7 cells were evaluated by quantitative real-time PCR (qRT-PCR) and cytochemical staining. In vivo, we used micro-CT to assess cortical bone mass and trabecular microstructures to reflect the influence of SDEs on bone remodeling after injection into the tail vein of rats. Based on proteomics analysis, 410 differentially expressed proteins, including 289 downregulated proteins and 121 upregulated proteins, were identified in the CPT-SDEs. These proteins have multiple biological functions associated with cellular metabolic processes, catalytic activity, and protein binding, which are important for cell differentiation and proliferation. In vitro, CPT-SDEs decreased the osteogenic differentiation of MC3T3-E1 cells and promoted the osteoclastogenesis of RAW264.7 cells. Injection of CPT-SDEs into the tail vein for two months resulted in bone loss in rats, as indicated by the decrease in trabecular and cortical bone mass. Our findings demonstrated the differences in proteins in SDEs between normal and CPT children with NF1. These differentially expressed proteins in CPT-SDEs contributed to deteriorating trabecular bone microstructures by inhibiting bone formation and stimulating bone resorption.

Are Some Randomized Clinical Trials Impossible?

Congenital tibial pseudarthrosis is a rare condition seen in neurofibromatosis type 1 (NF1), and treatment is complex. A randomized, placebo-controlled trial of bone morphogenetic protein (rhBMP-2; INFUSE bone graft) at time of tibial surgery was developed by the Neurofibromatosis Clinical Trials Consortium. Patients were randomized to receive rhBMP-2 that would, or would not, be added to the standard surgical procedure consisting of resection of pseudarthrosis tissue, insertion of a rigid intramedullary rod, and placement of autogenous iliac crest bone graft. Despite involvement of 16 centers with wide experience with NF1 orthopaedic management, only 5 patients (of 54 required) were able to be enrolled in the study during a 3-year time period. Because of the inability to recruit sufficient patients, this study was closed in June 2019, with plans to terminate. The obstacles that were encountered during the study are summarized. The authors question whether a randomized, placebo-controlled trial of a rare pediatric orthopaedic condition is possible to accomplish. Recommendations are provided to guide future studies of orthopaedic manifestations of NF1.Level of Evidence: Level V.

Résultats du traitement par la technique de la membrane induite des échecs du traitement chirurgical des pseudarthroses congénitales du tibia

BackgroundAlthough a remarkable success in the treatment of congenital pseudarthrosis tibia (CPT) had been achieved, failure rate is still high and the likelihood of amputation is still considerable. The current study evaluates the outcome of induced membrane technique in the treatment of failed previously operated patients of congenital pseudarthrosis of the tibia. We hypothesized that induced membrane technique will improve union rates in CPT with failed previous multiple operations. Patients and methodsNineteen consecutive patients of failed previously operated CPT were prospectively included in the study. All patients were treated by induced membrane technique with autogenous free non-vascularized fibular strut graft augmented by autogenous iliac graft and fixed by intramedullary K-Wire as well as Ilizarov external fixator. ResultsThe mean interval between the 1st and 2nd stages of the procedure was 4.9 weeks. Sound union was achieved in all cases in a mean time of 25.3 weeks. The mean follow up period was 5.02 years (range, 2.4–6.5). No refracture was documented till last follow up. ConclusionInduced membrane technique had proved as a successful method in the treatment of failed previously operated CPT with a satisfactory outcome and low complication rates. Level of evidenceIV.

Outcome of Induced Membrane Technique in Treatment of failed previously operated Congenital Pseudarthrosis of the Tibia

BackgroundAlthough a remarkable success in the treatment of congenital pseudarthrosis tibia (CPT) had been achieved, failure rate is still high and the likelihood of amputation is still considerable. The current study evaluates the outcome of induced membrane technique in the treatment of failed previously operated patients of congenital pseudarthrosis of the tibia. We hypothesized that induced membrane technique will improve union rates in CPT with failed previous multiple operations. Patients and methodsNineteen consecutive patients of failed previously operated CPT were prospectively included in the study. All patients were treated by induced membrane technique with autogenous free non-vascularized fibular strut graft augmented by autogenous iliac graft and fixed by intramedullary K-Wire as well as Ilizarov external fixator. ResultsThe mean interval between the 1st and 2nd stages of the procedure was 4.9 weeks. Sound union was achieved in all cases in a mean time of 25.3 weeks. The mean follow up period was 5.02 years (range, 2.4-6.5). No refracture was documented till last follow up. ConclusionInduced membrane technique had proved as a successful method in the treatment of failed previously operated CPT with a satisfactory outcome and low complication rates. Level of evidenceIV.

English

English

Research progress of Masquelet technique in the treatment of bone defects

Bone defects are usually resulted from traumatic injuries, infections, and bone tumors. The treatments mainly include autologous bone graft, allograft bone graft, distraction osteogenesis, vascularized bone grafting and amputation. All of the procedures show their inherent limitations due to different operative indications and different surgical techniques. The emergence of Masquelet technique provides a simple, safe, and more cost-effective solution in treating bone defects. The present article reviews the relevant literatures and summarizes the progress of Masquelet technique in the treatment of bone defects. The technique mainly includes two-step process which involves the induction of the induced membrane prior to the introduction of graft material into induced membrane. The first stage involves radical debridement of all infected or necrotic tissue, fracture stabilization, and filling the segmental bone defect with a cement spacer, composed of polymethyl methacrylate (PMMA) cement. Based on the results of culture performed on the wound samples, the sensitive antibiotics are mixed with cement for the infected bone defect. The second stage of bone grafting is performed within 6-8 weeks after the primary surgery. A longitudinal incision is performed through the induced membrane. The cement spacer is removed carefully and autogenous cancellous bone graft is placed to fill the bone defect and to close the induced membrane. A large number of experimental studies and clinical observations show that the induced membrane is a highly vascularized biological membrane rich in vascular endothelial growth factor (VEGF), transforming growth factor-β1(TGF-β1), bone morphogenetic protein 2 (BMP-2) and other growth factors, which can promote bone regeneration and repair. Masquelet technique can effectively treat multiple parts of posttraumatic bone defects, infectious bone defects, bone defects after tumor resection, congenital tibial pseudarthrosis, and so on. Masquelet provide a choice to treat bone defect for maxillofacial. The complications of Masquelet technique include infection recurrence, bone graft absorption, nonunion and pseudarthrosis. This study is to summarize the recent development of Masquelet technique, and to provide theoretical guidance for the application of Masquelet technique.

Concentration of several osteotropic growth factors, markers of osteogenesis and biologically active molecules in the blood serum of patients with congenital pseudarthrosis of tibia during orthopaedic treatment with combined technologies

Congenital pseudarthrosis of tibia is a genetic, systemic pathology with impaired bone remodeling and unknown pathogenetic mechanisms. Orthopaedic treatment of the disease can fail in some cases. The process of bone remodeling is known to occur under control of local and systemic growth factors, and we sought to explore several osteotropic growth factors, markers of osteogenesis and biologically active molecules in the blood serum of patients with congenital pseudarthrosis of tibia. The study included 12 patients with congenital pseudarthrosis of tibia and anatomical shortening of 2.5±1.1 cm. The' age of patients ranged from 7 years to 18 years. Blood serum was used for enzyme immunoassay analysis. The own blood serum levels of 103 conditionally healthy individuals (of mean age of 13.0±0.27 years) were considered as the norm. Greater changes in the concentration were detected among vascular endothelial and transforming growth factors. The patients showed imbalance in serum TGF, low reparative potential of bone tissue due to osteoclast activation prevailing over differentiation of osteoblasts, progenitor and mesenchymal cells. Dynamics in serum concentration of IGF at the time of frame removal indicated to terminating osteoblast activation and collagen synthesis and concomitant active bone restructuring.

Does pamidronate enhance the osteogenesis in mesenchymal stem cells derived from fibrous hamartoma in congenital pseudarthrosis of the tibia?

Neurofibromatosis type 1 (NF1) is a commonly occurring genetic disorder in children. Mutation in the NF1 gene has its implication in poor osteoblastic capabilities. We hypothesised that pamidronate will enhance the osteoblastic potential of the mesenchymal stem cells (MSCs) derived from lipofibromatosis tissue of children with congenital pseudarthrosis tibia (CPT) associated with NF1. In this study, bone marrow MSCs (BM MSCs) and CPT MSCs were obtained from three patients undergoing salvage surgeries/bone grafting (healthy controls) and those undergoing excision of the hamartoma and corrective surgeries respectively. The effects of pamidronate (0, 10nM, 100nM and 1μM) on cell proliferation, toxicity and differentiation potential were assessed and the outcome was measured by staining and gene expression. Our outcome showed that CPT MSCs had more proliferation rate as compared to BM MSCs. All 3 doses of pamidronate did not cause any toxicity to the cells in both the groups. The CPT MSCs showed less differentiation with pamidronate compared to the healthy control MSCs. This was quantitated by staining and gene expression analysis. Therefore, supplementation with pamidronate alone will not aid in bone formation in patients diagnosed with CPT. An additional stimulus is required to enhance bone formation.