Is Using a Ring External Fixator in the Treatment of Congenital Pseudarthrosis of the Tibia Associated With Better Results or Using a Locking Plate?

BACKGROUND

Congenital pseudarthrosis of the tibia (CPT) is a rare disease. CPT is often unilateral and occurs between the middle and distal third of the tibia. Concurrent involvement of the fibula is present in more than half of cases. histologic studies indicate the presence of fibrous hamartoma tissue and a sick periosteum, which leads to recalcitrant bone fracture and, eventually, pseudoarthrosis. Although there are various surgical techniques, we intend to compare the 2 methods of external fixation versus internal plating.

METHODS

Demographic data were collected from 26 patients with frank pseudoarthrosis. After exclusion criteria, patients were compared in groups A (12 patients) and B (11 patients). Resection of hamartoma and sclerotic bone, intramedullary rodding and autologous bone, and periosteal grafting were performed for all patients. In group A, we used a ring external fixator for compression and rotational stability, but in group B, a locking plate was used for these purposes.

RESULTS

Plating takes less time to use during surgery. In group A, the primary bony union was obtained in 67% of patients, while in group B, 82% of patients had a primary union. Meanwhile, the average time till the final union in group A was 6 months, while in group B, this time was 3.5 months. Positive union mass was obtained in 58% of the patients in group A and 82% of group B. In addition, plating prevented ankle valgus deformity in group B.

CONCLUSIONS

Permanent intramedullary rodding is a surgical requirement for correction of deformity and refracture prevention, but additional stability can be achieved with the use of a ring external fixator or internal plate. Cross union and positive union mass are 2 important factors in the treatment of pseudoarthrosis; these results are achieved to a greater extent and in a shorter period of time using the plate.

LEVEL OF EVIDENCE

level IV - case series.

Osteogenic organoid for bone regeneration: Healing of bone defect in congenital pseudoarthrosis of the tibia

BACKGROUND

Congenital pseudoarthrosis of the tibia (CPT) is an uncommon disease associated with failure to achieve bone union and recurrent fractures. There is evidence showing that CPT is associated with decreased osteogenesis. Based on the capacity of mesenchymal stromal cells (MSCs) to induce osteogenesis, we develop an osteogenic organoid (OstO) constituted by these cells, and other components of the bone niche, for inducing bone formation in a child diagnosed with CPT.

AIM

To evaluate the capacity of an OstO to induce bone formation in a patient with CPT.

METHODS

The OstO was fabricated with allogeneic bone marrow MSCs from a healthy donor, collagen microbeads (CM) and PRP clot. The CM and PRP function as extracellular matrix and scaffolds for MSC. The OstO was placed at the site of non-union. Internal and external fixation was placed in the tibia. Radiological evaluation was performed after MSCs transplantation.

RESULTS

After 4 months of MSCs transplantation, radiographic imaging showed evidence of osteogenesis at the site of CPT lesion. The tibia showed bone consolidation and complete healing of the non-union CPT lesion after 6 months. Functional improvement was observed after 1 year of MSC transplantation.

CONCLUSIONS

The OstO is a bone-like niche which promote osteogenesis in patients with failure in bone formation, such as CPT. To our knowledge, these results provide the first evidence showing CPT healing induced by an OstO constituted by allogeneic MSCs. Future studies incorporating a larger number of patients may confirm these results.

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.

[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.

Congenital Pseudarthrosis of the Tibia: Long-term Outcome of Treatment With Intramedullary Vascularized Fibular Graft Combined With Ilizarov Distraction

BACKGROUND

Late presenting cases of congenital pseudarthrosis of the tibia, are further complicated with severe shortening. Limb length discrepancy (LLD) cannot be corrected by vascularized fibular grafting and the use of Ilizarov distraction is associated with a high rate of complications. The aim of this study was to report the long-term follow-up of a combined technique previously published under the name "telescoping vascularized fibular graft".

MATERIALS AND METHODS

Eleven patients operated at an average age of 10.2±3.2 years were reviewed. All cases were Crawford type IV affected by neurofibromatosis 1. Nine patients had an average of 4.3 previous operations. Preoperative LLD averaged 7.9±2.5 cm.

RESULTS

Follow-up averaged 10±5.4 years. Seven cases (63.6%) reached skeletal maturity before final follow-up. Primary union was achieved in all cases after an average of 7.2±1.3 months. Full weightbearing was possible after an average of 10.6±2.2 months. Recurrent stress fractures occurred in 9 cases (81.8%) and healed with casting in 6 cases and required internal fixation in 3 cases. Eight cases (72.8%) developed tibial shaft deformities, mainly procurvatum that required corrective osteotomy in 2 cases. Final LLD averaged 2.7±1.3 cm. Complete tibialization of the graft was achieved after an average of 17.0 ± 3.6 months. Valgus deformity of the ipsilateral ankle averaged 12.4 degrees±7.5.

CONCLUSION

The presented technique avoids osteotomy of the diseased bone and allows simultaneous treatment of the pseudarthrosis and correction of shortening. Compared with conventional bone transport, it requires shorter time of frame application and therefore better patient tolerability because there is no waiting for consolidation of the regenerate. The dis-impaction of the doweled fibula occurs proximally, allowing the less active site located at the distal aspect of the pseudarthrosis to heal without displacement. A shortcoming of the presented technique is the more propensity for axial deviation and refractures that seldom require surgery.

LEVEL OF EVIDENCE

Level-IV.

The incidence of congenital pseudarthrosis of the clavicle and review of the literature

The aim of this study was to identify the hitherto unknown incidence of congenital pseudarthrosis of the clavicle (CPC), based on a cohort of continuous livebirths born in our hospital, to review the literature and investigate if there is evidence supporting the published association between left-sided CPC and dextrocardia. From our electronic medical record and radiology databases, we identified all live births and patients with the diagnosis of CPC born from 2000 to 2016. We reviewed the imaging which included one or both clavicles to search for unrecorded CPC cases and reviewed all retrievable CPC publications listed in PubMed and publications quoted within these publications going back to 1910. We identified 87 407 livebirths of which 41 800 had radiological studies done, 14 885 showing one or both clavicles. We found five cases of CPC, two from the electronic database and three from our imaging review, giving an incidence of 1 of 17 481 livebirths. We identified 138 publications reporting paediatric and adult CPC cases and 12 review articles, including 429 patients (187 female; 159 male; 83 unknown) with 456 CPCs and a minimum of 24 additional patients from case reports for which we could not retrieve details. Two publications reported one case of left-sided CPC with dextrocardia, either not showing left/right marking or only showing the CPC with the aortic knob on the same side. We report the first CPC incidence of 0.0057%, provide the by far most inclusive CPC epidemiology based on 429 patients and could not find reliable proof that there has ever been a patient with left-sided CPC which was associated with dextrocardia.

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

RATIONALE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Combination Treatment by Cross-Union of the Tibia and Fibula, Autogenic Iliac Bone Grafting, Reliable Fixation and Bone Morphogenetic Proteins for the Treatment of Refractory Congenital Pseudarthrosis of the Tibia

BACKGROUND

The treatment of congenital pseudarthrosis of the tibia (CPT) remains a challenge because of the difficulties of achieving and maintaining bone union, as well as complications of joint deformity and limb-length discrepancy. The purpose of this study was to evaluate the efficacy of cross-union of the tibia and fibula in achieving union and preventing refracture for patients with refractory CPT as a complementary approach to improve upon conventional surgical treatments.

METHODS

A retrospective study including patients with refractory CPT who attended our department between June 2014 and August 2020. Eighteen CPT patients, who had sustained refracture that required cast immobilization or secondary surgery, and were managed by pseudarthrosis resection, cross-union of the tibia and fibula, bone morphogenetic protein-2 and autogenous iliac bone grafting, were included. Clinical outcomes of the bone union rate and the frequency of refracture after performing cross-union of the tibia and fibula were assessed during the follow-up period.

RESULTS

The mean follow-up period was 4.3 years (range: 1.5 to 6.25 y). The mean age of the patients at surgery was 5.4 years (range: 2.6 to 10 y), and all 18 (100%) of the 18 patients had final healing at the site of pseudarthrosis. The average time spent to achieve radiologic bone union of the pseudarthrosis after operation was 2.96 months (range: 2.2 to 4.1 mo). Two (11.1%) patients had an average 2.5 cm limb-length discrepancy, none (0%) sustained refracture which needed cast immobilization or secondary surgery. Patients were all pain-free and move actively.

CONCLUSIONS

Cross-union of the tibia and fibula is a promising complementary procedure for treating refractory CPT patients.

LEVEL OF EVIDENCE

Level IV-case series.

Does An Osteotomy Performed in Congenital Pseudarthrosis of the Tibia Heal?

BACKGROUND

Shortening and deformity of the tibia commonly occur during the treatment of congenital pseudarthrosis of the tibia (CPT). The role of osteotomies in lengthening and deformity correction remains controversial in CPT. This study evaluates the approach to and outcome after osteotomy performed in CPT.

METHODS

We performed an IRB approved retrospective review of consecutive patients with CPT treated at our institution from 2010 through 2019. Patients who underwent osteotomies were included in this study.

RESULTS

Nine patients (10 osteotomies-5 proximal metaphyseal and 5 diaphyseal) with a median age at osteotomy of 8.9 years (range: 4 to 21 y) were included. Six patients had neurofibromatosis-1, 1 had cleidocranial dysplasia, and 2 patients had idiopathic CPT. Four osteotomies were performed for deformity correction, 3 osteotomies to allow intramedullary instrumentation, and 3 osteotomies for lengthening. Five osteotomies were preceded by zolendronate treatment before surgery. Nine were fixed with a rod supplemented with external fixation (7) or locking plates (2). One osteotomy was stabilized with locked intramedullary nailing alone. Four osteotomies were supplemented with autologous bone graft, and bone morphogenic protein-2 was utilized in 3 osteotomies. Median time to healing was 222.5 days (range: 124 to 323 d). One osteotomy (locked intramedullary nailing) required grafting at 5.5 months and then healed uneventfully. Median healing index for patients undergoing lengthening was 57.9 days/cm (range: 35 to 81 d/cm). All 3 osteotomies performed for lengthening required a second osteotomy for preconsolidation at a mean of 34 days. Other complications included compartment syndrome requiring fasciotomy (n=2), tibial osteomyelitis (n=1), and fracture distal to cross-union (n=1).

CONCLUSIONS

Contrary to much of the established practice, osteotomies may be safely performed in CPT for various indications. All osteotomies healed with only 1 osteotomy requiring secondary bone grafting. Although time to healing of the osteotomy was generally prolonged, this study suggests, somewhat surprisingly, that preconsolidation can occur frequently in lengthening procedures.

LEVEL OF EVIDENCE

Level IV-case series.

Congenital pseudarthrosis of the clavicle: a systematic review

PURPOSE

There is no consensus on the type of surgical treatment of congenital pseudarthrosis of the clavicle due to its rarity. The purpose of this study is to provide evidence in favor of a surgical technique and to explore factors correlated with bone consolidation.

METHODS

Systematic review of the literature and an analysis of the data for each subject, including all available subjects from the published series and clinical cases since 1990. Fisher's exact tests or T-tests were used to evaluate the effect of independent variables (age at surgery and type of treatment) on bone healing.

RESULTS

The literature search provides 305 articles; 30 were selected, reporting 191 patients and 194 clavicles. One hundred and fifty-one clavicles were operated on at a mean age of nine years and four months (from 8 months to 21 years). Thirteen clavicles (8, 6%) had not consolidated at the last follow-up. Concerning the type of fixation, the rate of healing was similar for plates and pins (p = 0.27). The rate of consolidation was higher with autograft than with allograft, xenograft, or no graft (p = 0.00001), and was 100% for vascularized graft. The mean age at surgery was higher for patients who healed at the last follow-up (118 vs. 61 months, p = 0.001).

CONCLUSION

In the event of surgical indication for congenital pseudarthrosis of the clavicle, it is recommended to perform autograft and stable fixation (level 4) after seven years old (level 4).

EXPERIMENTAL STUDY OF BONE DENSITY IN PATIENTS WITH CONGENITAL PSEUDOARTHROSIS OF THE TIBIA BEFORE AND AFTER SURGERY

OBJECTIVE

The aim: Determine the changes in bone density that occur in the cortical layer of the tibia in patients with CPT after surgical treatment due to radiography data.

PATIENTS AND METHODS

Materials and methods: The study was performed on X-rays of the tibia of three patients with CPT, aged 5 to 7 years. X-rays were taken before surgery and 1 year after surgery. The optical density of the cortical layer of both tibia bones was determined, for which they were conditionally divided into 7 zones.

RESULTS

Results: In all patients with CPT before treatment, there is significant decrease in the optical density of cortical bone tissue of the damaged tibia compared with contralateral. One year after surgery, there was an increase in the optical density of the cortical layer of both tibia of the studied patients. The increase in the density of the nonoperated tibia can be attributed to the active growth of patients. On the operated limb, the increase in the density of the cortical layer became statistically significant in all studied areas, which can be attributed not only to the growth of patients, but also to the possibility of active loading of the operated limb.

CONCLUSION

Conclusions: In all patients with CPT before treatment, a statistically significant decrease in the density of cortical bone tissue of the damaged tibia was observed. As a result of the treatment there is an approximation of the bone density of the operated limb to the indicators of intact contralateral bone.

Congenital pseudarthrosis of the forearm as a single manifestation of neurofibromatosis type 1 at birth: A case report

Congenital pseudoarthrosis of the forearm is an extremely rare condition. It is most commonly associated with neurofibromatosis type I (NF1). Patients with NF1-associated pseudoarthrosis have complex medical management and often require surgical intervention due to higher failure rates of union. In this case report, we present a unique case of a newborn baby with congenital pseudoarthrosis of both the radius and ulna that was manifested at birth and shortly thereafter, was diagnosed with NF type 1.

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.

Effectiveness of bone marrow aspirate concentrate (BMAC) as adjuvant therapy in the surgical treatment of congenital pseudoarthrosis of the tibia: a retrospective comparative study

Congenital pseudoarthrosis of the tibia (CPT) is a rare disease characterised by the onset of bone anomalies or fractures, leading to deformities in paediatric patients. The aetiology of this pathology is unknown. The main theories include the presence of hamartomatous tissue related to Neurofibromatosis type 1, vascularisation deficit of the periosteum and alterations in the numbers and functions of the osteoblasts and osteoclasts in loco. Surgical treatment generally requires multiple operations during the patient's childhood and adolescence. The best outcomes seem to occur when using intramedullary nailing, vascularised fibular transplant and external fixation with the Ilizarov technique. The purpose of this paper is to evaluate the effectiveness of in-situ injections of Bone Marrow Aspirate Concentrate (BMAC) as an adjuvant therapy for congenital pseudoarthrosis of the tibia in patients treated with external fixation and that of radiographic healing over time compared to external fixation treatment alone. We performed a retrospective review of clinical and radiographic records of patients affected by CPT and treated in the Paediatric Orthopaedics and Traumatology Department of the Gaetano Pini Orthopaedic Institute with in-situ injections of bone marrow aspirate concentrate (BMAC) on the pseudoarthrosis site, in addition to pseudoarthrosis site excision and application of circular external fixator frame in compression (Group A). The time needed to reach the radiological consolidation of the resection site was recorded and compared to that needed for patients treated with only pseudoarthrosis site excision and application of circular external fixator frame in compression (Group B). There is a statistically relevant improvement of healing time in patients affected by congenital pseudoarthrosis of the tibia treated with external fixation and bone marrow aspirate concentrate compared to patients affected by the same pathology treated with external fixation only. Injection of MSC in the pseudoarthrosis site after focus removal in combination with circular external fixation achieves faster bone healing compared with external fixation only, and the lower refracture percentage may be associated with the better quality and structure of the new bone. However, it would be desirable to have a longer followup to determine if the results of the BMC as adjuvant therapy will hold up over time.

Congenital pseudarthrosis of the tibia: Results of circular external fixation treatment with intramedullary rodding and periosteal grafting technique

OBJECTIVE

This study investigated the clinical and functional results of treating congenital pseudarthrosis of the tibia (CPT) using the combined techniques of hamartoma resection, periosteal grafting, circular external fixator application, and intramedullary rodding.

METHODS

The clinical and radiological data of 17 patients (mean age at the treatment time: 7.6 months (range: 4.6-9.7 months) with CPT, treated by a single surgeon between 1997 and 2017, were retrospectively analyzed. All data regarding surgical interventions, complications, deformity analysis parameters, limb length discrepancy (LLD), ankle joint range of motion, and residual deformities were reviewed. All the patients were followed up at least two years after the last surgical intervention. The mean follow-up time was 8.5 years (range: 2.2 to 15.7 years).

RESULTS

Union was achieved with the index treatment in 15 of the 17 cases (88.2%). The mean age of the patients at the last follow-up visit was 14.2 years (range: 7.6 to 22.1). The mean LLD was 2.1 cm. Nine patients had radiological ankle valgus at the last follow-up. In the entire series, eight patients did not display any complications, four cases reported minor complications, and five cases were complicated by refractures.

CONCLUSION

Circular external fixator application combined with periosteal grafting is a superior method of CPT treatment. This method provides a healthy biological healing environment while correcting the mechanical problems. The combination of periosteal and cancellous bone grafts with intramedullary rods and an external fixator addresses issues that complicate obtaining and maintaining a union during the CPT treatment.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.

Induced membrane technique for clavicle reconstruction in paediatric patients: Report of four cases

BACKGROUND

Clavicular reconstruction in paediatric patients is a rarely performed procedure that often raises complex technical challenges and produces unreliable outcomes. The induced membrane technique is an innovative two-stage procedure involving cement spacer placement into the defect to induce the development of a membrane, followed by the implantation of a cortical-cancellous bone graft. The primary objective of this study was to assess the medium- and long-term clinical and radiographic outcomes of clavicular reconstruction using the induced membrane technique in children and to highlight the advantages and drawbacks of this technique. The secondary objectives were to evaluate the fixation and the outcomes according to age and to the underlying diagnosis.

HYPOTHESIS

Clavicular reconstruction using the induced membrane technique produces good outcomes in paediatric patients.

PATIENTS AND METHODS

The induced membrane technique was used for clavicular reconstruction in 4 children with a mean age of 9.7 years (range, 7.4-12.3 years). The diagnosis was congenital pseudarthrosis of the clavicle in 3 patients and aneurysmal bone cyst in 1 patient. Shoulder pain and mobility were assessed at last follow-up. Radiological bone healing was evaluated using the total radiographic union score (RUS, range, 0-10). Complications and number of procedures per patient were recorded.

RESULTS

Mean follow-up was 3.9 years (range, 1-8.4 years). None of the patients had pain or motion range limitation. After 6 months, the clavicle was healed with a RUS of 10 in all patients. The mean number of surgical procedures per patient was 3.75 (range, 3-5). Two patients required revision surgery for distal pin migration and another for a subcutaneous abscess under the pin.

DISCUSSION

When used for clavicular reconstruction, the induced membrane technique is effective and associated with a low complication rate. The induced membrane technique therefore deserves to be viewed as an alternative to other methods.

LEVEL OF EVIDENCE

IV, retrospective observational study.

Treat the congenital pseudarthrosis of the Tibia with Ilizarov technology: Case report

RATIONALE

According to previously published studies, treating pediatric patients with congenital pseudarthrosis of the tibia (CPT) is challenging. More effective methods are needed to treat this patient population.

PATIENT CONCERNS

A 7-year-old girl with congenital pseudarthrosis of the distal tibia, previously misdiagnosed as a fracture, underwent plate fixation. Unfortunately, the steel plate broke after 3 months, which led to ankle angle deformity.

DIAGNOSES

Congenital pseudarthrosis of the tibia.

INTERVENTION

Treat the congenital pseudarthrosis of the tibia with Ilizarov technology.

OUTCOMES

lower limb force recovery, bone union, and lower-limb-length equalization were achieved. Congenital pseudarthrosis of the tibia were cured.

LESSONS

The Ilizarov technique is a safe, effective, and practical treatment option for patients with CPT.

Wrapping grafting for congenital pseudarthrosis of the tibia: A preliminary report

OBJECTIVE

Treatment of congenital pseudarthrosis of the tibia (CPT) remains a challenge. The autogenic iliac bone graft is important consistent of treatment for CPT. The purpose of this study was to investigate the role of wrapping autogenic iliac bone graft in improvement of the curing opportunities of CPT.

METHODS

We combined Ilizarov fixator with intramedullary rodding of the tibia and wrapping autogenic iliac bone graft for treatment 51 cases of CPT between 2007 and 2010. The mean age is 3.2 years at index operation, of which 31 patients (61%) were below 3 years old. According to Crawford classification, 5 tibia had type-II morphology; 3, type-III; 43, type-IV.

RESULTS

In the postoperative follow-up of 3.5 months (range from 3 to 4.5 months), all cases were found that the bone graft sites of pseudarthrosis of the tibia showed a significant augmentation and spindle-shaped expansion as obvious change. All cases of this series have been followed-up, average followed-up time were 1.6 years (range from 7 to 3.1 years), of which 19 cases were more than 2 years. The average time of removed the Ilizarov ring fixator was 3.5 months (range from 3 to 4.5 months). According to Johnston Clinical evaluation system, 26 cases had grade I, 21 cases, grade II, 4 cases, grade III. Following the Ohnishi X-ray evaluation criteria, union of pseudarthrosis of the tibia were 42 cases, delayed union 5 cases, nonunion 4 cases.

CONCLUSION

Autogenic iliac bone graft is able to offer the activity of osteoblasts and osteogenesis induced by bone morphogenetic protein (BMP) and glycoprotein, meanwhile enclosing bone graft could help keep cancellous bone fragments in close contact around pseudarthrosis of the tibia, allowing the formation of high concentration of glycoprotein and BMP induced by chemical factors because of established the sealing environment in location, all of which could enhance the healing of pseudarthrosis of the tibia.

Bone morphogenetic protein-2 for the treatment of congenital pseudarthrosis of the tibia or persistent tibial nonunion in children and adolescents: A retrospective study with a minimum 2-year follow-up

There is a lack of studies reporting on rhBMP-2 application in pediatric orthopaedics, although few reports demonstrated promising results of the use of rhBMP-2 in children, especially for spine fusion and for the treatment of congenital pseudarthrosis of the tibia. The objectives of this study were (1) to examine clinical and radiographic healing after rhBMP-2 application for the treatment of congenital pseudarthrosis of the tibia (CPT) or persistent tibial nonunion in children and adolescents, and (2) to investigate the safety of rhBMP-2 use in these cases. Therefore we reviewed the medical records of ten patients with a mean age of 8.6 years (2.3-21) with CPT (n = 7) or persistent tibial nonunion for at least six months (n = 3) who had been treated with rhBMP-2. Nine of ten patients had union at final follow-up, after a mean of 72.9 months (25-127). In the CPT group, primary healing of the pseudarthrosis occurred in six of seven patients at a mean of 5.2 months (3-12). Repeat rhBMP-2 application was performed in three patients; two patients had one additional application each, and one patient had three additional applications. Complications that may be attributed to the use of rhBMP-2 were seen in two of fifteen applications, including a compartmemt syndrome and a hematoma. In this retrospective case series rhBMP-2 has been used successfully to treat CPT or persistent tibial nonunion in pediatric patients. However, prospective randomized controlled trials are warranted to investigate the long-term efficacy and safety of rhBMP-2 use in these cases.

[A man with remarkable clavicles]

A 26-year-old male complained of painful clavicles. His medical history included multiple fractures of both clavicles, all treated conservatively. Conventional radiographs revealed a typical shape of both clavicles, suggesting non-union. His extraordinary medical history and non-union of both clavicles led to the diagnosis: 'congenital pseudarthrosis of both clavicles'.

TREATMENT OF CONGENITAL PSEUDARTHROSIS OF THE TIBIA

The work is based on an analysis of treatment results of 47 patients with congenital pseudarthrosis of the tibia. The Ilizarov technique of unfree osteoplasty was applied on these patients. The authors considered an application of combined variants of exterior and external osteosynthesis as very perspective in rehabilitation of the patients with congenital pseudarthrosis.

Isolation and Characterization of Multipotential Mesenchymal Stromal Cells from Congenital Pseudoarthrosis of the Tibia: Case Report

Congenital pseudoarthrosis of the tibia (CPT) is an uncommon disease whose etiology and pathogenesis is unknown. Several evidences suggest that decreased osteogenic capacities, impaired local vascularization, and microenvironment alterations may play a role in the pathogenesis of CPT. Additionally, it is not clear if the pathogenesis of this disease is related to the absence of cells with osteogenic capacity of differentiation. In this work, a two-year-old patient diagnosed with CPT underwent an orthopedic surgery to promote bone union in a pseudoarthrosis lesion. Tissue from CPT lesion was excised, and histological evaluation and tissue culture were performed. Histologic analysis of the soft CPT lesion showed the presence of highly cellular fibrous tissue, vascularization, and abundant extracellular matrix. Fusiform cells of mesenchymal appearance were observed but osteoblasts, osteoclasts, chondrocytes, and adipose cells were not found. There was no evidence of osteogenesis. CPT tissue cultured as explants showed, after one month of culture, evidence of osteogenesis, chondrogenesis, and adipogenesis. Cells isolated from explants of CPT tissue showed a fibroblast-like morphology and expressed the mesenchymal stromal cell (MSC) markers: CD105, CD73, and CD90 (CPT-MSC). Functional analysis showed that CPT-MSC differentiate, in vitro, into osteogenic, chondrogenic, and adipocytic cells. CPT-MSC expressed osteocalcin and agrecan. CPT-MSC produced collagen in the presence of ascorbic acid. MSC from BM of normal individuals were used as control. In summary, our results indicate that CPT tissue contains MSC with osteogenic capacity of differentiation. It is possible that CPT microenvironment may contribute to impair the osteogenic capacity of differentiation of CPT-MSC.

[Utility of morphogenetic protein for the treatment of congenital pseudoarthrosis of the tibia]

OBJECTIVE

To report the ability of bone morphogenetic protein to achieve bone healing in patients with congenital pseudoarthrosis of the tibia.

PATIENTS AND METHODS

Three patients with a diagnosis of congenital pseudoarthrosis of the tibia were followed-up for six months. Bone healing and functional capacity of the limb were observed.

RESULTS

Bone healing occurred in all cases at a mean of three and half months of treatment.

CONCLUSIONS

Morphogenetic protein is useful as an adjuvant to achieve bone regeneration and healing in patients with congenital pseudoarthrosis of the tibia.

Use of vascularised free fibula in limb reconstruction (for non-malignant defects)

The case series was conducted at the Department of Plastic Surgery, Combined Military Hospital, Rawalpindi, from June 2009 to May 2011, and comprised 19 patients in whom free fibula flap was performed for upper and lower limb reconstruction, using SPSS 16. Results showed that flap survival was 100%. One (5.2%) flap was re-explored for venous congestion and was salvaged. One (5.2%) patient of congenital pseudoarthrosis of tibia had a fracture of the fibula and was treated with external fixation. Average follow up was 8 months. Mean union time and full weight-bearing was 6.5 +/- 1.34 months (range 3-8 months) and 9 months, respectively. No recurrence of pseudoathrosis was observed until the last follow up, with only a 1.5 cm length discrepancy in one patient. The results proved that a microvascular free fibular flap heals rapidly, causes early functional recovery and it can be raised as an osteocutaneous flap.

Free vascularized fibular transfer with langenskiöld procedure for the treatment of congenital pseudarthrosis of the forearm

Congenital pseudarthrosis of the radius or ulna is a rare entity. It is associated with neurofibromatosis, but occurs much less commonly than congenital pseudarthrosis of the tibia. Pseudarthrosis of the forearm can lead to pain, deformity, and limited forearm rotation. Nonsurgical management leads to poor results, as do surgical treatments such as open reduction internal fixation and conventional bone grafting. The transfer of a free vascularized fibula to the forearm pseudarthrosis has been more successful, and it is our preferred method of treatment for children with this condition. Because the transfer is often performed in young children, there is the potential for valgus deformity at the ankle after the fibula is removed. We describe here our technique for the transfer, including the technique for distal tibiofibular fusion (Langenskiöld procedure) after removal of the fibular graft. In addition, we present the results of 5 patients who have undergone this combination of procedures for pseudarthrosis of the forearm at our institution.

First successful case of non-invasive in-utero treatment of twin reversed arterial perfusion sequence by high-intensity focused ultrasound

High-intensity focused ultrasound (HIFU) has excellent potential as a non-invasive therapeutic tool in various fields of medicine. We present a case of twin reversed arterial perfusion sequence, in which non-invasive blood flow occlusion in the acardiac fetus was successfully achieved by means of HIFU exposure from outside the maternal abdomen. HIFU was applied to blood vessels of the acardiac fetus at the point at which the umbilical cord entered the body in a series of four procedures at 3-day intervals starting at 13 weeks' gestation, and in a final procedure with higher power at 17 weeks. The HIFU intensity was set at approximately 2300 W/cm(2) for the initial series of procedures and at 4600 W/cm(2) for the final procedure, with exposure periods of 10 s. As color Doppler examination revealed absence of blood flow to the acardiac fetus after the second round of HIFU exposure, we concluded that complete occlusion of target vessels had been achieved. Delivery was by Cesarean section at 37 weeks' gestation. A male neonate (the pump fetus) was born weighing 1903 g with Apgar scores of 8 and 9 at 1 and 5 min, respectively. At the time of writing, the baby was healthy and growing normally, with the exception of congenital pseudarthrosis.

Vascularized bone grafts for the management of skeletal defects in orthopaedic trauma and reconstructive surgery

Bone loss from trauma, neoplasia, reconstructive surgery and congenital defects remains a major health problem. The long-term clinical goal is to reconstruct bony tissue in an anatomically functional three-dimensional morphology. In the extremities, bone grafts are used for the treatment of non-unions and necrotic lesions, for skeletal structural support and for the reconstruction of defects resulting from trauma, tumor excision, osteomyelitis, congenital pseudarthrosis, or radiation necrosis. In all cases their use is successful provided that the host bed has adequate vascularization. In cases of decreased blood supply, a vascularized bone graft should be applied. The intrinsic blood supply of the vascularized bone grafts leads to higher success rates and to acceleration of the repair process in the reconstruction of defects and necrotic lesions of the skeleton.

Is double inactivation of the Nf1 gene responsible for the development of congenital pseudarthrosis of the tibia associated with NF1?

The pathogenic mechanism responsible for congenital pseudarthrosis of the tibia (CPT) is not well understood although the possibility of double inactivation of the neurofibromatosis type 1 (Nf1) gene has been suggested. In the present study, loss of heterozygosity was investigated in fibrous hamartoma tissues harvested from 16 patients with CPT associated with NF1 using four genetic markers that span the Nf1 gene. Based on the assumption that a single cell with double inactivation of Nf1 would undergo clonal growth and cause fibrous hamartoma, we investigated clonality in fibrous hamartoma tissues by analyzing X-chromosome inactivation patterns in 11 female patients. Loss of Nf1 heterozygosity in fibrous hamartoma tissues was observed at one or two genetic markers in 4 out of the 16 patients tested. In clonality assays, 3 of 11 patients showed a clonal growth pattern, 5 a non-clonal pattern, and 3 were non-informative. These findings support that double inactivation of the Nf1 gene and subsequent clonal growth could be a pathogenic feature of the fibrous hamartoma tissue at least in some of the CPT but might not be essential requirements of CPT development.

[Early reconstruction of congenital pseudoarthrosis of the tibia with free vascularized fibular grafts]

Congenital pseudoarthrosis of the tibia (CPT) is an uncommon disease presenting a tibial nonunion since birth and frequently associated to neurofibromatosis type 1. Surgical management by wide excision of the pseudoarthrosis and sustitution of the defect with vascularized bone in an early stage has proven to be the most effective technique in terms of bone consolidation. We present a clinical case of a 22-month-old patient with CPT treated successfully by reconstruction with a free vascularized fibula graft with an excellent functional result.

Advantages of intramedullar fixation in treatment of congenital tibial pseudoarthrosis--a case report

This report describes a case of a 29-year old patient with congenital pseudoarthrosis of the distal tibia previously treated unsuccessfully by a conventional surgical method. Tibial congenital pseudoarthrosis is a rare disease characterized by segmental osseous weakness resulting in deformation of the bone and spontaneous fractures which progresses to a tibial nonunion. In our case we used intramedullary stabilization with bone grafting and six month after operation congenital pseudarthrosis of the tibia healed.

Biological basis for the use of autologous bone marrow stromal cells in the treatment of congenital pseudarthrosis of the tibia

The study was designed to establish the biological basis for the use of autologous bone-marrow stromal cells (MSC) in order to improve the curing opportunities of congenital pseudarthrosis of the tibia (CPT). The investigation was planned by taking into account that the pathophysiology of bone healing mainly depends on the osteogenic potential of the resident cells, although several factors play a crucial role in restoring the normal bone structure. Bone marrow samples were collected from the lesion site (P) and the iliac crest (IC) of 7 patients affected by CPT and type 1 neurofibromatosis (NF1+) and 6 patients affected by CPT without NF1 (NF1-). Four patients without CPT served as control group. Biochemical, functional and molecular assays showed that the ability to generate bone-forming cells was higher in IC-MSC than in P-MSC, but lower in CPT patients than in control group. We evaluated whether host factors, such as autologous serum and the microenvironment surrounding the pseudarthrosis lesion, could impair the osteogenic differentiation of IC-MSC. Autologous serum was less effective than FBS in promoting the IC-MSC differentiation, but the damage was more evident in NF1- than in NF1+ patients. Additionally, the supernatant of osteoblast cultures obtained from bone fragments close to the lesion site favoured the differentiation of IC-MSC in NF1- patients. In summary, our results suggest that MSC transplantation could be a promising strategy for the therapy of CPT. Further studies are warranted to confirm the clinical effectiveness in comparison to standard surgical treatment.

Congenital pseudarthrosis of the tibia: an atypical proximal location

Proximal location of congenital pseudarthrosis of the tibia (CPT) is uncommon, and its management challenging, risking to end in amputation. We here report a case of proximal CPT managed in a limb-sparing perspective and followed up until the end of growth. A 17-year-old girl presented with type-1 neurofibromatosis and proximal CPT. Initial X-ray showed severe pseudarthrosis of the tibia with bone atrophy, 12-cm shortening and femorotibial and femoropatellar dislocation. Inter-tibiofibular graft and fibular tibialization were performed. At end of follow-up (age 33 years), fusion had been obtained. For orthoprosthetic and cosmetic reasons, a Boyd amputation of the tarsus was performed when the patient was 22 years of age. The functional result was very good, with 0-100 degrees knee mobility. CPT, when proximal, completely disorganizes the knee joint, which is otherwise usually unaffected by this pathology. To achieve a good result, a limb-sparing treatment should combine correction of the tibial axis and of the dislocation of the knee, fibula osteosynthesis and bone graft.

LEVEL OF EVIDENCE

Level IV retrospective

Congenital pseudarthrosis of neurofibromatosis type 1: impaired osteoblast differentiation and function and altered NF1 gene expression

Three patients with neurofibromatosis 1 (NF1) were operated for congenital pseudarthrosis (PA) of the tibia. Three non-NF1 patients served as reference. Both NF1 mRNA and protein were detected in the PAs and in rows of osteoblasts and numerous osteoclasts next to the NF1-related PA arguing against inactivation of both NF1 alleles in the resident cells. Analyses on mesenchymal stem cells (MSCs) cultured from the red bone marrow of 1) next to PA of the affected NF1 tibiae, 2) the non-affected NF1 iliac crest of the same patients, and from 3) non-NF1 bone marrow demonstrated that the potential to form bone in vitro was the lowest in cells from the affected NF1-tibiae. The latter cells also displayed reduced levels of NF1 mRNA and protein, and upregulated phosphorylated p44/42 MAPK levels, consistent with an upregulated Ras-pathway. An exhaustive NF1 gene analysis detected constitutional mutation in each case, but no second hits or loss of heterozygosity were found. However, one patient displayed a mutation resulting in two potential active splice sites ultimately affecting exon 6. Interestingly, only one of the respective transcripts was detected in cells from the iliac crest, but two novel transcripts were detected in MSCs cultured from site next to PA. This finding may identify a novel mechanism how a single NF1 gene mutation may exert distinct effects on separate anatomical locations. The molecular pathogenesis of NF1-related PA apparently may not be entirely explained by second mutations or loss of heterozygosity of the NF1 gene.

Vascularized free fibular graft in the treatment of congenital pseudarthrosis of tibia

Aim of the study was to evaluate the results of the patients with "congenital pseudartrosis of tibia" treated by vascularized fibular graft transferred from the contralateral calf.

MATERIAL AND METHODS

The cohort consist of four patients (2 boys and 2 girls) aged 5.75 y (range 4-8 years) in the time of the transfer of vascularized fibular graft from the contralateral calf into the resected tibia suffered from pseudarthrosis Crawford type II, III and IV. Patients were operated on between 1999-2007.

RESULTS

A total graft union was achieved in three patients in one-year follow-up period. In one girl, treatment failed due to infection and was treated later with intramedullar Rush nail fixation and additional spongioplasty with an unsatisfactory result.

CONCLUSION

Authors believe that after an accurate preoperative planning in cooperation with the microsurgeon, the treatment of congenital pseudarthrosis of the tibia by vascullarized fibular graft should be considered as a very effective, accurate and relatively safe method (Tab. 2, Fig. 4, Ref. 7). Full Text (Free, PDF) www.bmj.sk.

Congenital osteofibrous dysplasia of the tibia, associated with pseudoarthrosis of the ipsilateral fibula

We describe an otherwise normal male neonate who presented shortly after birth with rare congenital osteofibrous dysplasia of the right tibia associated with pseudoarthrosis of the ipsilateral fibula. The lesion was curetted, and the defect was packed with a fibular bone graft from the other leg. Histopathological examination was typical for osteofibrous dysplasia. The ipsilateral fibular pseudoarthrosis was observed with no active intervention. Seven years follow-up showed good functional recovery without recurrence of the lesion. The case is a new presentation of congenital osteofibrous dysplasia, and is presented to draw attention to this rare condition that must be considered in the differential diagnosis of congenital lesions of the tibia.

Congenital pseudoarthrosis of the clavicle: is operative treatment necessary? A report of four cases and literature review

Congenital pseudoarthrosis of the clavicle (CPC) is not a common condition. The exact number of cases reported in literature is fewer than two hundred. We present four well-documented cases of true congenital pseudoarthrosis of the clavicle, including two cases of familial occurrence. None of the patients in this study were treated surgically. Evaluation of upper extremity function was done with use of the Constant-Murley method. In spite of clavicle pseudoarthrosis the score results were similar to the unaffected shoulder. Although vertical elevation of the upper ribs or cervical ribs has been suggested as a cause of congenital clavicle lesions, radiological examination failed to reveal such pathology in any of the patients described here. Clavicle pseudoarthrosis is generally regarded as a benign condition. The majority of patients who underwent surgery because of cosmetic or functional heal well and proceed with a normal, unrestricted life. However, for those patients who are not bothered by the cosmetic appearance of their CPC and are asymptomatic in that they are not functionally limited, non-surgical treatment is a viable option.

Congenital unilateral pseudarthrosis of the olecranon

Congenital pseudarthrosis of the olecranon is a rare condition. Three isolated cases with bilateral presentation, different treatment modalities and variable outcome were reported in the orthopaedic literature. In this presented case a pseudarthrosis of the right olecranon in a 13-year-old boy was treated by pseudarthrosis resection, bone graft interposition and tension band osteosynthesis. Hardware removal was performed nine months after the initial procedure. At 6-year follow-up at the end of growth, the patient has no pain and a free range of motion of his dominant right elbow. This (to our knowledge) first case of unilateral pseudarthrosis of the olecranon had an excellent clinical result with stable fixation and support of bone healing by a bone graft interposition.

Surgical treatment of congenital pseudarthrosis of the clavicle: a report on 17 cases

Congenital pseudarthrosis of the clavicle (CPC) is a rare malformation of uncertain aetiopathogenesis, usually unilateral. Physical examination reveals swelling over the midportion of the clavicle, often asymptomatic; the diagnosis is confirmed by radiology. Treatment is controversial: for many authors the surgical indications are the presence of symptoms, functional impairment or cosmetic deformities. We present a retrospective analysis of 17 children with CPC treated in our institutions: 9 were treated with plate (P) and 8 with Kirschner wire (KW) fixation; a bone graft was used in 12 cases only. Five patients (4 P and 1 KW) needed a second surgical procedure. The surgical treatment led to a very good result in 7 cases, good in 4 cases, fair in 3 cases and poor in 3 other cases. We recommend early treatment of all patients with CPC with resection of the pseudarthrosis, autologous iliac bone grafting and internal fixation with Kirschner wires.

[Congenital pseudoarthrosis of the clavicle in a boy with Prader-Willi's syndrome]

The authors present the case of a boy with congenital pseudoarthrosis of the right clavicle who met all clinical and auxologic criteria of Prader-Willi's syndrome. Poor cooperation due to mental retardation was the reason for the primary conservative treatment. During this, deformity of the middle clavicle progressed, but without development of subjective complaints and functional deficit. At his 16 years, this cosmetic defect became unacceptable for his parents and, later than it is usually recommended, resection of pseudoarthrosis with plate osteosynthesis and autologous spongioplasty was indicated. The sufficient skeletal maturation and size of both fragments allowed us to perform stable osteosynthesis with the use of a contoured reconstruction plate, without the risk of insufficient osteosynthesis or clavicle fracture after the removal of osteosynthetic material.

Treatment of congenital pseudarthrosis of the tibia with native bovine BMP: a case report

Bone morphogenetic proteins (BMP) have been shown to induce bone formation and union in long bone defects and nonunions. We report a case of congenital pseudarthrosis of the tibia treated with a composite implant consisting of a biocoral frame, collagen carrier, and native bovine BMP extract. A six-year-old boy had persisting congenital proximal tibial pseudarthrosis despite six prior operations. At surgery, the sclerotic surfaces of both fragments were excised, fixation was performed using Ilizarov's device, and the composite implant and an autograft were applied to the nonunion site. Three months after the operation, radiographs showed union, and at four months, the Ilizarov device was removed. Two years later, the proximal pseudarthrosis remained clinically and radiologically united. It is concluded that BMP may contribute to the healing of congenital tibial pseudarthrosis of the tibia.

Congenital pseudarthrosis of the tibia: analysis of the histology and the NF1 gene

BACKGROUND

Congenital pseudarthrosis of the tibia (CPT) is frequently, but not always, associated with neurofibromatosis type 1 (NF1). Double inactivation of the NF1 gene has been reported to be the pathogenesis of CPT in NF1 cases.

METHODS

We analyzed the loss of heterozygosity (LOH) of the NF1 gene in cases of CPT with NF1 to examine whether double inactivation was seen in the case. In addition to morphological analysis, immunoexpression of differentiation markers was examined.

RESULTS AND DISCUSSION

The tibia tapered with the zone phenomenon from mature to immature bone with osteoblastic rimming, resembling osteofibrous dysplasia. Osteosclerotic bowed bone with a small number of osteoclasts suggested dysfunction of bone remodeling. Fibrous tissue at the site of pseudarthrosis was associated with the periosteum and demonstrated myofibroblastic differentiation accompanied by massive cartilage formation, suggesting some misdirection during the differentiation of periosteum to myofibroblasts or chondrocytes. LOH of the NF1 gene locus was not seen in fibrous tissue. This result suggests that CPT is not accompanied by double inactivation in every NF1 case.

Congenital pseudoarthrosis associated with venous malformation

Congenital pseudoarthrosis is a pathologic entity that may be isolated, or may be associated with neurofibromatosis. We report the case of a 3-year-old female with congenital pseudoarthrosis involving the right tibia and fibula. Magnetic resonance imaging (MRI) and complementary magnetic resonance angiogram (MRA) revealed a lobulated mass with vivid enhancement, which led to the diagnosis of venous malformation. This is the first report of congenital pseudoarthrosis caused by the presence of a vascular malformation.

Congenital osteofibrous dysplasia associated with pseudoarthrosis of the tibia and fibula

The association between congenital pseudoarthrosis and osteofibrous dysplasia of the tibia and fibula is a rare entity that has been recently recognized. We report a male newborn who was found to have swelling and deformity of the left lower leg. Radiographs and magnetic resonance imaging showed an extensive destructive lesion of the tibial shaft, with dysplastic congenital pseudoarthrosis of the lower fibula. Histopathological examination confirmed the diagnosis of congenital pseudoarthrosis of the tibia and fibula with underlying osteofibrous dysplasia involving both bones. Immunohistochemical stains showed cytokeratin positivity.

Congenital pseudarthrosis of the clavicle: a case report

Congenital pseudarthrosis of the clavicle is a rare entity of unknown aetiology. Its pathogenesis is related to the embryology of the clavicle. We present a 6-year-old girl with congenital pseudarthrosis of the right clavicle. A prominence was noticed at birth between the middle and distal ends of the clavicle that increased in size when the right shoulder was actively mobilised. Radiographic examination revealed a hypertrophic pseudarthrosis of the clavicle. The pseudarthrosis was resected and the clavicular segments were fixed with an external fixator for 2 months until union. Clinical results were excellent at the 7-year follow-up: the right shoulder was pain-free and the appearance satisfactory. Surgical treatment of congenital pseudarthrosis of the clavicle in children using an external fixator provides a better cosmetic outcome with smaller postoperative scars and avoids a second surgical procedure to remove the implants.

Congenital pseudarthrosis of the ulna

We report a case of congenital pseudarthrosis of the ulna along with generalized neurofibromatosis (type I). The patient had a good clinical outcome after single-bone forearm reconstruction. In the setting of radial head dislocation following long-standing congenital pseudarthrosis of the ulna, single-bone forearm reconstruction is a viable option. It prevents the loss of hand function by the effective shortening of flexor tendons and spares movements of the humeroulnar and radiocarpal joints.

Successful Treatment of Congenital Pseudarthrosis of the Tibia with Long Segment Fibular Allografting in a Young Child

Congenital pseudarthrosis of the tibia (CPT) in young children with large bone defect after surgical resection can be difficult to reconstruct. Structural allograft may be a useful alternative in such cases but data are limited. We report a girl 1 year and 10 months of age with CPT successfully treated with en bloc resection of there current extensive pseudarthrosis, intramedullary rod placement, and long-segment intercalary allografting with supplemental autograft of the bony defect. At 6 years of follow-up, radiographs showed equal leg lengths, with good incorporation into the host bone. This method is technically simple and less time-consuming. It may be considered as an alternative method to the other more complicated procedures, such as microvascular fibula graft or the Ilizarov technique, in such a young child.

Isolated congenital pseudarthrosis of the fibula: clinical course and optimal treatment

The purposes of this study were to determine the clinical course of isolated congenital pseudarthrosis of the fibula (ICPF) and to establish optimal treatment guidelines for this disease. Thirteen fibulae in 12 patients with ICPF were followed for an average of 6.2 years. Twelve of the 13 fibulae were regarded to originally have had a pre-pseudarthrotic condition. Five fibulae remained intact during follow-up, but 8 developed pseudarthrosis. Two cases with established pseudarthrosis were observed for ankle alignment change without intervention, and in 4 cases successful fibular osteosynthesis maintained the ankle alignment. The remaining 2 adolescent cases presenting with ankle valgus were treated using the Ilizarov technique and distal tibiofibular synostosis. ICPF follows a unique clinical course, which should be taken into consideration along with fibular status, ankle alignment, and patient age when planning treatment.