Ilizarov bone transport as a treatment of congenital pseudarthrosis of the tibia: a long-term follow-up study

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.

Preventing of nonunion in congenital pseudarthrosis of the tibia cases of Crawford Type I and II through the use of allograft bypass and a brace: Midterm findings

Background

Congenital pseudarthrosis of the tibia is a limb deformity, which can be distressing for the affected patients and the pediatric orthopedic surgeons involved. We hypothesized that the modified McFarland procedure would avoid fractures and even have a corrective effect on the affected tibia in congenital pseudarthrosis of the tibia patients. Toward this end, we evaluated the midterm results of treating congenital pseudarthrosis of the tibia patients of Crawford Type I and II with allograft bypass combined with long-term bracing.

Methods

This study retrospectively evaluated 7 patients with congenital pseudarthrosis of the tibia who were treated with allograft bypass combined with long-term bracing between 2009 and 2018. The median follow-up was 7.0 years (range 3.8-10.0 years). The medical records and radiographs were reviewed for demographic data, clinical characteristics, outcomes, and complications.

Results

At the time of the last follow-up, all allografts revealed complete consolidation in the patients' tibiae at both ends. All patients presented no functional restriction of the lower limbs and no amputation or non-union has occurred. Most of the obvious deformities of the tibia diaphysis or ankle joint were corrected. Two complications occurred that required successful revision surgery.

Conclusion

In this series of seven congenital pseudarthrosis of the tibia patients, the allograft bypass technique showed satisfactory midterm results and validated our hypothesis. For congenital pseudarthrosis of the tibia patients of Crawford Type I and II, this procedure combined with long-term bracing, which involves the affected leg only, can delay or possibly prevent fractures, decrease tibial malalignment, and preserve leg length.

Level of evidence

level IV.

Association between preoperative concurrent fibular pseudarthrosis and risk of postoperative ankle valgus in patients with congenital pseudarthrosis of the tibia

BACKGROUND

This study evaluated the correlation of preoperative concurrent fibular pseudarthrosis with the risk of ankle valgus deformity in patients with congenital pseudarthrosis of the tibia (CPT) who underwent successful surgical treatment.

METHOD

The children with CPT who were treated at our institution between 1 January 2013 and 31 December 2020 were retrospectively reviewed. The independent variable was preoperative concurrent fibular pseudarthrosis, and the dependent variable was postoperative ankle valgus. Multivariable logistic regression analysis was performed after adjusting for variables that might affect the risk of ankle valgus. Subgroup analyses with stratified multivariable logistic regression models were used to assess this association.

RESULTS

Of the 319 children who underwent successful surgical treatment, 140 (43.89%) developed ankle valgus deformity. Moreover, 104 (50.24%) of 207 patients with preoperative concurrent fibular pseudarthrosis developed an ankle valgus deformity compared with 36 (32.14%) of 112 patients without preoperative concurrent fibular pseudarthrosis (p=0.002). After adjusting for sex, body mass index, fracture age, age of patient undergoing surgery, surgery method, type 1 neurofibromatosis (NF-1), limb-length discrepancy (LLD), CPT location and fibular cystic change, patients with concurrent fibular pseudarthrosis presented a higher risk of ankle valgus than those without concurrent fibular pseudarthrosis (OR 2.326, 95% CI 1.345 to 4.022). This risk further increased with CPT location at the distal one-third of the tibia (OR 2.195, 95% CI 1.154 to 4.175), age <3 years of patient undergoing surgery (OR 2.485, 95% CI 1.188 to 5.200), LLD <2 cm (OR 2.478, 95% CI 1.225 to 5.015) and occurrence of NF-1 disorder (OR 2.836, 95% CI 1.517 to 5.303).

CONCLUSION

Our results indicate that patients with CPT and preoperative concurrent fibular pseudarthrosis have a significantly increased risk of ankle valgus compared with those without preoperative concurrent fibular pseudarthrosis, particularly in those with CPT location at the distal third, age <3 years at surgery, LLD <2 cm and NF-1 disorder.

Analysis of risk factors affecting union and refracture after combined surgery for congenital pseudarthrosis of the tibia: a retrospective study of 255 cases

Background

Congenital pseudarthrosis of the tibia (CPT) is a rare disease occurring in children. The aim of this study is to identify the factors affecting bone union and re-fracture after surgery for CPT and to provide reliable evidence for clinics.

Methods

We collected the detailed information of 255 cases with Crawford IV CPT treated by combined surgery in our hospital from 2013 to 2020. Basic characteristics were recorded. Univariate variance and logistic regression analysis were used to compare the correlations between factors and outcomes.

Results

92.5% of patients achieved primary union, 7.5% of patients had non-union and 13.3% of patients had re-fracture. Logistic regression analysis showed that age at index surgery (Coef. = 0.171, 95%CI 0.015–0.327, P = 0.032), and CPT location (Coef. = − 1.337, 95%CI − 2.218–0.456, P = 0.003) had statistical differences, while no factors had significant correlation with re-fracture. Furthermore, ROC curve showed that the optimal age threshold for first surgery was 2.37 years old.

Conclusions

For patients with Crawford IV CPT treated by combined surgery, the younger the age at index surgery and the closer the CPT location to the distal end, the easier to achieve bone union.

Combination of the Ilizarov Method and Intramedullary Fixation for the Treatment of Congenital Pseudarthrosis of the Tibia in Children: A Retrospective Observational Study

Purpose

Congenital pseudoarthrosis of the tibia (CPT) is a rare disease in children, and its treatment remains a challenge for orthopedic surgeons. The purpose of this study was to evaluate treatment outcomes of patients with CPT treated by using the Ilizarov method combined with intramedullary fixation.

Method

Eighteen patients evaluated retrospectively from January 2009 to January 2020 were treated using the Ilizarov method combined with intramedullary fixation. Demographic data, clinical characteristics, and complications were all recorded and investigated during the period of follow-up. Ankle function was evaluated by the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores at the last follow-up.

Result

The average follow-up was 39.2 months (25–85 months) for all 18 patients. The mean age was 6.2 years (3.5–11.2 years). Fourteen (77.8%) patients had a primary bone union at the site of pseudarthrosis, while four obtained union after secondary surgical intervention. The mean duration of the Ilizarov method was 8.1 months (4.2–13.5 months). Eight (44.4%) patients had a pin-tract infection during treatment. Four (22.2%) patients had proximal tibial valgus with a mean angle of 12.1° (5–25°), while seven (38.9%) patients had ankle valgus deformities with a mean of 10.3° (5–20°). Eleven (61.1%) patients had an average 1.4 cm of limb length discrepancy (LLD) (0.6–3.1 cm) postoperatively. Five (27.8%) patients had refracture and recovered after a secondary surgery. At the last follow-up, the average postoperative AOFAS score was 72 (55–84).

Conclusion

The Ilizarov method combined with intramedullary fixation is an effective method for the treatment of CPT, which can facilitate bony union and help to prevent refracture. Management of fibular pseudarthrosis is associated with functional outcomes. It is necessary to follow up until skeletal maturity and evaluate long-term clinical outcomes.

Exosome-Laden Hydrogels: A Novel Cell-free Strategy for In-situ Bone Tissue Regeneration

In-situ bone tissue regeneration, which harnesses cell external microenvironment and their regenerative potential to induce cell functions and bone reconstruction through some special properties of biomaterials, has been deeply developed. In which, hydrogel was widely applied due to its 3D network structure with high water absorption and mimicking native extracellular matrix (ECM). Additionally, exosomes can participate in a variety of physiological processes such as cell differentiation, angiogenesis and tissue repair. Therefore, a novel cell-free tissue engineering (TE) using exosome-laden hydrogels has been explored and developed for bone regeneration in recent years. However, related reviews in this field are limited. Therefore, we elaborated on the shortcomings of traditional bone tissue engineering, the challenges of exosome delivery and emphasized the advantages of exosome-laden hydrogels for in-situ bone tissue regeneration. The encapsulation strategies of hydrogel and exosomes are listed, and the research progress and prospects of bioactive hydrogel composite system for continuous delivery of exosomes for in-situ bone repair are also discussed in this review.

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.

Orthopaedic manifestations of neurofibromatosis type 1: A case report

Neurofibromatosis type 1 (NF1) or von Recklinghausen disease is one of the most common autosomal dominant genetic diseases. It is characterized by ‘café-au-lait’ spots and multiple tumors starting from the central and peripheric nervous system. The diagnosis is determined on two out of seven criteria: i) A total of 6 or more light brown spots larger than 5 mm in diameter (pre-puberty) or 15 mm in diameter (post-puberty); ii) a total of 2 or more neurofibromas or one plexiform neurofibroma; iii) axillary or inguinal freckling; iv) optic glioma; v) a total of 2 or more Lisch nodules; vi) bone abnormalities: tibia pseudarthrosis or dysplasia of the sphenoid wing; and vii) a relative of first degree having an NF1 diagnosis. A total of ~50% of patients have significant musculoskeletal manifestation, with scoliosis and congenital pseudarthrosis of tibia most common. Management of the orthopaedic manifestations of NF1 is often difficult. Due to NF1 influencing multiple organ systems, patients are likely to benefit most from a multidisciplinary treatment strategy.

Piezoelectric hybrid scaffolds mineralized with calcium carbonate for tissue engineering: Analysis of local enzyme and small-molecule drug delivery, cell response and antibacterial performance

As the next generation of materials for bone reconstruction, we propose a multifunctional bioactive platform based on biodegradable piezoelectric polyhydroxybutyrate (PHB) fibrous scaffolds for tissue engineering with drug delivery capabilities. To use the entire surface area for local drug delivery, the scaffold surface was uniformly biomineralized with biocompatible calcium carbonate (CaCO₃) microparticles in a vaterite-calcite polymorph mixture. CaCO₃-coated PHB scaffolds demonstrated a similar elastic modulus compared to that of pristine one. However, reduced tensile strength and failure strain of 31% and 67% were observed, respectively. The biomimetic immobilization of enzyme alkaline phosphatase (ALP) and glycopeptide antibiotic vancomycin (VCM) preserved the CaCO₃-mineralized PHB scaffold morphology and resulted in partial recrystallization of vaterite to calcite. In comparison to pristine scaffolds, the loading efficiency of CaCO₃-mineralized PHB scaffolds was 4.6 and 3.5 times higher for VCM and ALP, respectively. Despite the increased number of cells incubated with ALP-immobilized scaffolds (up to 61% for non-mineralized and up to 36% for mineralized), the CaCO₃-mineralized PHB scaffolds showed cell adhesion; those containing both VCM and ALP molecules had the highest cell density. Importantly, no toxicity for pre-osteoblastic cells was detected, even in the VCM-immobilized scaffolds. In contrast with antibiotic-free scaffolds, the VCM-immobilized ones had a pronounced antibacterial effect against gram-positive bacteria Staphylococcus aureus. Thus, piezoelectric hybrid PHB scaffolds modified with CaCO₃ layers and immobilized VCM/ALP are promising materials in bone tissue engineering.

Reconstructive Approaches in Surgical Management of Congenital Pseudarthrosis of the Tibia

Treatment of congenital pseudarthrosis of the tibia remains a major challenge in pediatric orthopedics. Ideal timing and preference of surgical procedures are discussed controversially. A variety of reconstructive treatment strategies have been described in literature, but so far none has proven its superiority. The aim of treatment is to obtain long-term bone union, to prevent refracture, and to correct angular deformities and leg length discrepancies. This study retrospectively evaluates the outcome of different reconstructive strategies. Sixty-nine patients were identified who presented to our outpatient department between 1997 and 2019. Twenty-six of these patients underwent reconstructive surgical treatment and were included in this study. The study cohort was divided into three groups. Excision of the pseudarthrosis was performed in all patients in Group A and B, and in two patients of Group C. Group A (six/26 patients) received subsequent bone transport through external fixation maintaining original length. In Group B (15/26 patients), patients underwent either previous, simultaneous, or subsequent extrafocal lengthening through external fixation to reconstitute length. In Group C (five/26 patients), internal fixation with intramedullary nails was applied. Radiological and clinical evaluation was performed to assess bone union and complication rates. Results varied considerably between the study groups. Overall, the primary bone fusion rate was 69.2%. There were four refractures, all occurring in Group B. The long-term bone union rate without refracture was 53.8%. The overall complication rate was 53.8% and 23.1% showed persistent pseudarthrosis. Two secondary amputations were performed due to failed bone fusion. In conclusion, excision of the pseudarthrosis and extrafocal lengthening achieves a satisfying bone union rate and limb reconstruction, while bone transport does not offer significant advantages but shows higher complication rates. Intramedullary stabilization should be applied to maintain bone union, but shows lower bone union rates when used as a stand-alone treatment regimen. Regardless of the primary bone fusion rates, the probability of long-term bone union remains unpredictable.

Distal Tibial Guided Growth for Anterolateral Bowing of the Tibia: Fracture May Be Prevented

BACKGROUND

Congenital pseudarthrosis of the tibia is a rare and challenging pediatric condition. The pre-fracture state, called congenital tibial dysplasia or anterolateral bowing of the tibia, presents a high fracture risk due to underlying bowing and dysplasia. After fracture, there is a substantial risk of nonunion. Any union achieved may be complicated by refracture, deformity, leg-length discrepancy, stiffness, pain, and dysfunction. We present the results of using distal tibial growth modulation to improve tibial alignment and to decrease fracture risk in this condition. To our knowledge, this is the first report of isolated distal tibial growth modulation as the primary surgical treatment for this condition.

METHODS

This is a retrospective study of 10 patients with congenital tibial dysplasia who presented prior to pseudarthrosis and underwent distal tibial growth modulation as a primary treatment. The medical records and radiographs were reviewed for age at the times of diagnosis and treatment, fracture, secondary procedures, complications, residual deformity, cystic changes, and leg-length discrepancy.

RESULTS

Ten patients had a mean follow-up (and standard deviation) of 5.1 ± 1.9 years. No patient sustained a tibial fracture, and no patient developed a tibial pseudarthrosis after guided growth was initiated. The mean age at the initiation of growth modulation was 2.6 ± 1.3 years. Six patients required a plate exchange. The mean residual tibial diaphyseal angular deformity at the most recent follow-up was 4.3° ± 3.2° of varus and 8.4° ± 5.8° in the sagittal plane. Only 1 patient had a clinically important leg-length discrepancy, with the affected leg being longer.

CONCLUSIONS

In this series of 10 patients with congenital tibial dysplasia, distal tibial growth modulation delayed or possibly prevented fracture, decreased tibial malalignment, improved radiographic appearance of bone quality, and preserved leg length. No patient developed tibial fracture or pseudarthrosis after the initiation of guided growth treatment. Although early results are promising, follow-up to maturity is required to define the exact role of this simple outpatient procedure in congenital tibial dysplasia.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Delivery of Extracellular Vesicles Loaded in Biomaterial Scaffolds for Bone Regeneration

Extracellular vesicles (EVs) are heterogeneous nanoparticles actively released by cells that comprise highly conserved and efficient systems of intercellular communication. In recent years, numerous studies have proven that EVs play an important role in the field of bone tissue engineering (BTE) due to several advantages, such as good biosafety, stability and efficient delivery. However, the application of EVs therapies in bone regeneration has not been widely used. One of the major challenges for the application of EVs is the lack of sufficient scaffolds to load and control the release of EVs. Thus, in this review, we describe the most advanced current strategies for delivering EVs with various biomaterials for the use in bone regeneration, the role of EVs in bone regeneration, the distribution of EVs mediated by biomaterials and common methods of promoting EVs delivery efficacy with a focus on biomaterial properties.

What's New in Pediatric Limb Lengthening and Deformity Correction?

Over the past 5 years, published literature regarding treatment of pediatric limb deformity and limb length discrepancy demonstrates much interest in better understanding, categorizing and treating these challenging problems. Many studies explore expanding and refining indications for traditional treatment methods like guided growth techniques. Other studies have evaluated the results of new techniques such as lengthening via mechanized intramedullary nails. Additionally, series comparing older and newer techniques such as lengthening with external devices versus mechanized nails are becoming increasingly available.

Combined technique with hydroxyapatite coated intramedullary nails in treatment of anterolateral bowing of congenital pseudarthrosis of tibia

Purpose

The goal of this study is to evaluate the treatment outcomes of anterolateral bowing and residual deformities of distal tibia in patients with CPT using circular external fixation and hydroxyapatite coated flexible intramedullary nailing without excision of affected part of tibia.

Patients and methods

Six patients (4 boys and 2 girls, mean age 12.4 ± 4.1 years) were included in the study. Mean follow-up is 2.1 years. In 4 patients with early onset of disease initial surgical treatment (at age of 5-8 years) was dysplastic zone or pseudarthrosis resection with proximal metaphyseal osteotomy for bone transport. Children with unbroken bowed tibia (2 cases of type II according to Crawford classification) had no previous surgery. Neurofibromatosis type I was diagnosed in 4 cases. Surgical technique for residual deformity correction consisted of percutaneous osteotomy, application of circular external frame and composite hydroxyapatite-coated intramedullary nailing.

Results

Mean external fixation time was 95.3 ± 17.5 days. All patients never get fractured after frame removal. At the present time, they are considered to be healed, in 2.1 years, in average, without fractures or deformity recurrence. Mean lower limb length discrepancy varied from 2 to 10 mm at the latest follow-up control. After realignment procedure, patients didn't require additional surgery but one. Intramedullary nails were removed in two years after deformity correction for individual reason.

Conclusion

Correction of anterolateral bowing or residual deformity in children with CPT is indicated. Association of external fixation with intramedullary nailing/rodding left in situ after frame removal ensure stability and accuracy of deformity correction. Biological methods of stimulation of bone formation in dysplastic zone are obligatory to ensure bone union. Intramedullary nailing with composite hydroxyapatite-coated surface provides mechanical and biological advantages in patients with CPT.

Physeal and Subphyseal Distraction Osteogenesis in Atrophic-type Congenital Pseudarthrosis of the Tibia: Efficacy and Safety

PURPOSE

To examine the efficacy, safety, and clinical outcomes of distraction osteogenesis through the physis (PDO) or through subphyseal osteotomy (SPDO) in patients with atrophic-type congenital pseudarthrosis of tibia with proximal tibial dysplasia.

METHODS

To validate the efficacy and safety of PDO and SPDO, radiographic and clinical parameters were compared between 5 patients who underwent proximal tibial metaphyseal or metadiaphyseal lengthening as a control (group 1) and 7 patients who underwent PDO or SPDO (group 2). Postoperative complication was also compared between the groups.

RESULTS

A significant difference in terms of healing index (group 1, 83.3±24.7 d/cm; group 2, 35.0±11.1 d/cm; P=0.001) and percentage increase (11.0%±3.7% vs. 23.1%±10.5%, P=0.034) was observed between the 2 groups. According to the Paley classification, group 1 included 1 "problems" case and 3 "obstacles" cases, whereas group 2 included 2 "problems" cases and 1 "obstacles" case. According to the Lascombes classification, group 1 included 2 grade IIIb cases and 3 grade IV cases, whereas group 2 included 6 grade I cases and 1 grade IIa case. Severe complications were significantly higher in group 1 compared with the group 2 (P=0.007).

CONCLUSIONS

This study demonstrated that PDO or SPDO can be effectively and safely performed for tibial lengthening in atrophic-type congenital pseudarthrosis of tibia patients with proximal tibial dysplasia.

LEVEL OF EVIDENCE

Level III.

Management of Congenital Pseudoarthrosis of the Tibia and Fibula

PURPOSE OF REVIEW

Congenital pseudoarthrosis of the tibia and fibula are rare conditions that share common treatment strategies. The purpose of this review is to provide an overview of the recent developments in treatments for both conditions.

RECENT FINDINGS

Recent literature has focused on the use of BMP and on gait analysis as a tool for measuring long-term functional outcomes. Recent study has indicated rhBMP-2 may shorten the time to initial healing of pseudoarthroses, but not guarantee bony union. Children with initial fractures before the age of four have been shown to have long-term gait outcomes that may be ultimately comparable to children with prostheses. Both congenital pseudoarthrosis of the tibia and fibula are challenging conditions to treat, which require comprehensive approaches to account for both the biological and mechanical components of the conditions.

Congenital Pseudarthrosis of the Tibia: Results, at Skeletal Maturity, of the Charnley-Williams Procedure

Background

This study assessed the outcomes, at skeletal maturity, for 34 patients in whom congenital pseudarthrosis of the tibia (CPT) had been treated with intramedullary (IM) rod fixation.

Methods

The results in skeletally mature patients in whom type-4 CPT had been treated with an IM rod at an average of 11.9 years earlier were reviewed. The rod procedures varied according to whether both the tibia and the fibula were resected and both bones (type A) or just the tibia (type B) were fixed with an IM rod or whether only the tibia was resected and the fibula received no surgery (type C). Outcome grading ranged from unequivocal union with brace-free function (grade 1) to a functional limb with residual angulation or cortical defects (grade 2) to a severely impaired extremity with insufficient union or refracture (grade 3).

Results

Thirty-four patients were evaluated at a mean age of 16.9 years, a mean of 11.9 years after their initial surgical procedure. Seventeen patients had a grade-1 result; 11 patients, grade 2; and 6, grade 3. Thus, 82% (28) of the 34 patients had a functional extremity at maturity. All patients with a final grade-3 outcome eventually requested amputation. The final outcomes were not affected by the age at the initial fracture or surgery, the presence of neurofibromatosis-1, or cross-ankle fixation. A total of 58 IM rod procedures were performed in the 34 patients. Twenty-four (73%) of the 33 type-A procedures produced grade-1 or 2 outcomes, as did 14 (88%) of the 16 type-B procedures. Of the 9 type-C procedures, none produced a grade-1 result and 4 produced a grade-2 outcome. The results of types A and B combined were superior to those of type-C procedures (p = 0.03). Refracture occurred in 13 of 33 patients with initial stability/union after rod fixation, with 3 of those fractures remaining ununited at the latest follow-up. A dystrophic fibula had no effect on the eventual achievement of a grade-1 or 2 outcome.

Conclusions

This review, in which all patients had reached skeletal maturity, documents functional (grade-1 or 2) outcomes in 82% of cases of IM rod fixation for CPT. This finding was almost identical to the result in our earlier report and confirms the long-term value of permanent IM rod fixation in maintaining union and function in patients with CPT. Procedures not addressing the fibula produced inferior results. Although 13 patients had a refracture following initial union, only 3 of these fractures failed to heal with additional treatment.

Level of Evidence

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Neurofibromatosis type 1-related pseudarthrosis: Beyond the pseudarthrosis site

Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder affecting approximately 1 in 2,000 newborns. Up to 5% of NF1 patients suffer from pseudarthrosis of a long bone (NF1-PA). Current treatments are often unsatisfactory, potentially leading to amputation. To gain more insight into the pathogenesis we cultured cells from PA tissue and normal-appearing periosteum of the affected bone for NF1 mutation analysis. PA cells were available from 13 individuals with NF1. Biallelic NF1 inactivation was identified in all investigated PA cells obtained during the first surgery. Three of five cases sampled during a later intervention showed biallelic NF1 inactivation. Also, in three individuals, we examined periosteum-derived cells from normal-appearing periosteum proximal and distal to the PA. We identified the same biallelic NF1 inactivation in the periosteal cells outside the PA region. These results indicate that NF1 inactivation is required but not sufficient for the development of NF1-PA. We observed that late-onset NF1-PA occurs and is not always preceded by congenital bowing. Furthermore, the failure to identify biallelic inactivation in two of five later interventions and one reintervention with a known somatic mutation indicates that NF1-PA can persist after the removal of most NF1 negative cells.

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.

Current treatment of congenital pseudarthrosis of the tibia: a systematic review and meta-analysis

To compare the current treatments for congenital pseudarthrosis of tibia, a total of 33 studies were reviewed. Vascularized fibular graft with external fixation or combined fixation had the fastest time till initial union (P<0.05). Bone morphogenetic protein had no advantage in terms of initial union, time till union, and refracture rates. This meta-analysis supports that fixation methods with corticocancellous bone autograft utilizing the combined technique of Ilizarov external fixation and intramedullary rod stabilization ensure a statistically significant reduction in the number of refractures compared with standalone fixation methods and would be the preferred method for preventing long-term complications in patients with congenital pseudarthrosis of tibia.

Bone regeneration strategies: Engineered scaffolds, bioactive molecules and stem cells current stage and future perspectives

Bone fractures are the most common traumatic injuries in humans. The repair of bone fractures is a regenerative process that recapitulates many of the biological events of embryonic skeletal development. Most of the time it leads to successful healing and the recovery of the damaged bone. Unfortunately, about 5-10% of fractures will lead to delayed healing or non-union, more so in the case of co-morbidities such as diabetes. In this article, we review the different strategies to heal bone defects using synthetic bone graft substitutes, biologically active substances and stem cells. The majority of currently available reviews focus on strategies that are still at the early stages of development and use mostly in vitro experiments with cell lines or stem cells. Here, we focus on what is already implemented in the clinics, what is currently in clinical trials, and what has been tested in animal models. Treatment approaches can be classified in three major categories: i) synthetic bone graft substitutes (BGS) whose architecture and surface can be optimized; ii) BGS combined with bioactive molecules such as growth factors, peptides or small molecules targeting bone precursor cells, bone formation and metabolism; iii) cell-based strategies with progenitor cells combined or not with active molecules that can be injected or seeded on BGS for improved delivery. We review the major types of adult stromal cells (bone marrow, adipose and periosteum derived) that have been used and compare their properties. Finally, we discuss the remaining challenges that need to be addressed to significantly improve the healing of bone defects.

Managing large bone defects in children: a systematic review of the 'induced membrane technique'

Thirty years after its description by Masquelet in 1986, this is the first systematic review aiming to critically evaluate the 'induced membrane technique' effectiveness in achieving bone union in children. Only six papers fulfilled our inclusion criteria (54 patients). The relatively small number of reported cases did not allow a formal meta-analysis. The tibia was the most involved bone. Most frequent aetiologies were congenital pseudoarthrosis and tumour resections. Although effective in achieving bone healing in ∼91% of the patients (bone defects ≤24 cm long), the induced membrane technique was associated with a high rate of complications (54% of patients).

LEVEL OF EVIDENCE

IV.

Anterolateral Bowing of Congenital Pseudoarthrosis of Tibia Treated by Percutaneous Osteotomy and Gradual Correction Using Taylor Spatial Frame, then Late Insertion of a Fussier-Duval Nail: A Case Report

Patient: Male, 12

Final Diagnosis: Congenital pseudoarthrosis of tibia

Symptoms: Limp • deformity

Medication: —

Clinical Procedure: Percutaneous osteotomy and gradual correction

Specialty: Orthopedics and Traumatology

Masquelet technique versus Ilizarov bone transport for reconstruction of lower extremity bone defects following posttraumatic osteomyelitis

OBJECTIVE

This study was to compare the effectiveness of Masquelet technique versus Ilizarov bone transport in the treatment of lower extremity bone defects following posttraumatic osteomyelitis.

PATIENTS AND METHODS

We retrospectively reviewed 39 patients who had been treated at our department for lower extremity bone defects following posttraumatic osteomyelitis. They were 30 males and 9 females with a mean age of 39.18 (range, 12-63 years). The infected bone defects involved 26 tibias and 13 femurs. The mean length of the bone defects after radical debridement was 6.76cm (range, 2.7-15.7cm). Masquelet technique (MT, group A) was used in 20 patients and Ilizarov bone transport (IBT, group B) in 19 ones. The measurements were bone outcomes (union, deformity, infection and leg-length discrepancy) and functional outcomes (significant limping, joint contracture, soft tissue dystrophy, pain and inactivity).

RESULTS

The mean follow-up after removal of the apparatus was 25.26 months (range, 14-51 months). The mean finite fixator time was 10.15 months (range, 8-14 months) in group A versus 17.21 months (range, 11-24 months) in group B. The bone outcomes were similar between groups A and B [excellent (5 vs. 7), good (10 vs.9), fair (4 vs. 2) and poor (1 vs. 1)]; group A showed better functional outcomes than group B [excellent (8 vs. 3), good (9 vs. 6), fair (3 vs. 8) and poor (0 vs. 2)].

CONCLUSIONS

In the treatment of segmental lower extremity bone defects following posttraumatic osteomyelitis, both IBT and MT can lead to satisfactory bone results while MT had better functional results, especially in femoral cases. IBT should be preferred in cases of limb deformity and MT may be a better choice in cases of periarticular bone defects.

Relationship between postoperative complications and fibular integrity in congenital pseudarthrosis of the tibia in children

BACKGROUND

This study aimed to investigate the relationship between postoperative complications and fibular integrity in congenital pseudarthrosis of the tibia (CPT) in children.

METHODS

A retrospective study was performed in 59 patients with Crawford type IV CPT who were treated with combined surgical technique from 2007 to 2011. The patients were divided into two groups, the CPT with fibular pseudarthrosis (group A) and CPT with intact fibula groups (group B), on the basis of fibula status after the union of CPT. The incidence rates of refracture, ankle valgus, tibial valgus, and limb length discrepancy in the two groups were investigated.

RESULTS

In group A, 14 (36.8%) cases had refracture, 30 (78.9%) had ankle valgus; 27 (71%) exhibited tibial valgus with an average tibial valgus of 7° (6°-20°), and 24 (63.2%) had limb length discrepancy with an average limb length of 1.26 cm (0.6-4.4 cm). In group B, 2 (9.5%) cases had refracture, 11 (52.4%) had ankle valgus, 8 (42.9%) had tibial valgus with an average tibial valgus deformity of 2.9° (6°-13°), and 13 (61.9%) had limb length discrepancy with an average limb length of 1.48 cm (0.5-5 cm). Significant difference in refracture and ankle valgus was found between groups A and B (P<0.05).

CONCLUSIONS

After the union of CPT, patients with fibular pseudarthrosis showed higher incidence of refracture and ankle valgus than those with intact fibula. Attention should be paid to the presence of fibular pseudarthrosis when managing CPT.

Contribution of G.A. Ilizarov to bone reconstruction: historical achievements and state of the art

Methodological solutions of Prof. G.A. Ilizarov are the core stone of the contemporary bone lengthening and reconstruction surgery. They have been acknowledged in the orthopaedic world as one of the greatest contributions to treating bone pathologies. The Ilizarov method of transosseous compression–distraction osteosynthesis has been widely used for managing bone non-union and defects, bone infection, congenital and posttraumatic limb length discrepancies, hand and foot disorders. The optimal conditions for implementing distraction and compression osteogenesis were proven by numerous experimental studies that Prof. G.A. Ilizarov organized and supervised at a large orthopaedic research institute in Kurgan. The tension stress effect on regeneration and growth of tissues was thoroughly investigated with radiographic, histological and biochemical methods. The impact of the Ilizarov method on the progress of bone lengthening and reconstruction surgery could be called revolutionary.