Vascularized free fibular bone graft in the management of congenital tibial pseudarthrosis

Comparison of limb reconstruction with vascularized fibula flap versus induced membrane technique in 54 pediatric cases over 16 years

BACKGROUND

Children's bone loss of limbs represents a significant challenge for surgeons, especially given that children are growing individuals. In the pediatric population, we compared bone reconstruction using vascularized fibula flaps with the induced membrane technique. The primary purpose of this study was to evaluate the delay and quality of consolidation.

METHODS

Data from patients who underwent limb reconstruction using either the fibula flap or the induced membrane were retrospectively collected from files across two centers. Perioperative and long-term complications were documented, along with functional and aesthetic outcome.

RESULTS

Between 2004 and 2020, 31 children underwent limb reconstruction using a fibula flap, and 13 patients were treated using the induced membrane technique. The etiologies included 76% tumors, 20% congenital pseudarthroses, and 3.7% infections. The median size of the bone resection was 12.5 cm (range: 1.8 to 31 cm). The median time to consolidation after free fibula flap transfer was 10 months (range: 2 to 55 months) versus 7.5 months (range: 1 to 64 months) for the Masquelet technique (p = 0.54). Limb length inequality occurred in 52% of fibula cases and 39% of the induced membrane cases (p = 0.55).

CONCLUSIONS

Both of free fibula flap and the induced membrane technique are effective options for bone reconstructing long bones in children. These techniques yield good functional outcomes and have comparable consolidation times.

Pseudoarthrosis of the Femur Secondary to Tuberculosis: A Rare and First Report

Tuberculosis poses a major health problem worldwide, and more so in developing countries. Tuberculosis will exist for as long as there are facets of malnutrition, poor sanitation, overcrowding, and immunocompromised populations. We report a rare case of pseudoarthrosis of the femur secondary to tuberculosis. A five-year-old female child presented with swelling, discharging sinuses, and abnormal mobility in the right lower one-third of the thigh secondary to trauma seven months ago. Incision, drainage, and debridement were done, and the obtained pus showed no growth. The sample turned out to be acid-fast bacilli-positive. The patient was on anti-tubercular drugs for six months and had a protective plaster cast for about six weeks, following which knee mobilization was started. During knee mobilization, the patient underwent a forced manipulation of the lower end of the femur, and the radiograph revealed a pathological fracture for which one-and-a-half hip-spica was applied. Further radiographs revealed an un-united fracture after three months despite hip spica application, and a pseudoarthrosis of the right distal femur developed, for which non-vascularized fibular strut grafting for pseudoarthrosis of the distal third of the femur was performed and stabilized with two 2.5 mm-long K-wires supplemented with hip spica for six months. The patient was followed up regularly, and subsequent radiographs showed fibular uptake and resolution of pseudoarthrosis of the femur at the eighth-month follow-up. The patient showed complete resolution of pseudoarthrosis and an excellent functional outcome by the end of the two-year follow-up.

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.

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.

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.

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.

Biocompatibility of single-walled carbon nanotube composites for bone regeneration

OBJECTIVES

The purpose of this study was to evaluate in vivo biocompatibility of novel single-walled carbon nanotubes (SWCNT)/poly(lactic-co-glycolic acid) (PLAGA) composites for applications in bone and tissue regeneration.

METHODS

A total of 60 Sprague-Dawley rats (125 g to 149 g) were implanted subcutaneously with SWCNT/PLAGA composites (10 mg SWCNT and 1gm PLAGA 12 mm diameter two-dimensional disks), and at two, four, eight and 12 weeks post-implantation were compared with control (Sham) and PLAGA (five rats per group/point in time). Rats were observed for signs of morbidity, overt toxicity, weight gain and food consumption, while haematology, urinalysis and histopathology were completed when the animals were killed.

RESULTS

No mortality and clinical signs were observed. All groups showed consistent weight gain, and the rate of gain for each group was similar. All groups exhibited a similar pattern for food consumption. No difference in urinalysis, haematology, and absolute and relative organ weight was observed. A mild to moderate increase in the summary toxicity (sumtox) score was observed for PLAGA and SWCNT/PLAGA implanted animals, whereas the control animals did not show any response. Both PLAGA and SWCNT/PLAGA showed a significantly higher sumtox score compared with the control group at all time intervals. However, there was no significant difference between PLAGA and SWCNT/PLAGA groups.

CONCLUSIONS

Our results demonstrate that SWCNT/PLAGA composites exhibited in vivo biocompatibility similar to the Food and Drug Administration approved biocompatible polymer, PLAGA, over a period of 12 weeks. These results showed potential of SWCNT/PLAGA composites for bone regeneration as the low percentage of SWCNT did not elicit a localised or general overt toxicity. Following the 12-week exposure, the material was considered to have an acceptable biocompatibility to warrant further long-term and more invasive in vivo studies. Cite this article: Bone Joint Res 2015;4:70-7.

Congenital pseudarthrosis of the tibia: the results of an evolving protocol of management

PURPOSE

This retrospective cohort study assesses the outcomes of a protocol of management, based on the recommendations of the European Paediatric Orthopaedic Society (EPOS) multi-centre study, for the management of congenital pseudarthrosis of the tibia.

METHODS

Utilising an incremental protocol of bracing, intramedullary rods and circular frame fixation with or without bone morphogenetic protein-2 (BMP-2), 11 patients had reached skeletal maturity or had follow up of 5 years from radiological union of the pseudarthrosis. Demographic data, deformity parameters before and after treatment, and functional outcome scores were recorded.

RESULTS

Ten of the 11 patients successfully healed and two sustained a refracture. All deformity parameters improved and a mean leg length discrepancy of 2.5 cm (range 0-7.5 cm) existed at the time of the last follow up. Some pseudarthroses healed with deformity correction and rod insertion alone. Six of the 11 patients had a confirmed diagnosis of neurofibromatosis and nine had sustained a fracture before 4 years of age. Refracture was associated with malalignment after healing.

CONCLUSION

This method of treatment provides a successful stepwise protocol for the management of this complex disorder, avoiding the use of aggressive limb reconstruction techniques at a young age in some cases. Level of evidenceCase series Level IV.

Approaches to treating NF1 tibial pseudarthrosis: consensus from the Children's Tumor Foundation NF1 Bone Abnormalities Consortium

BACKGROUND

Neurofibromatosis 1 (NF1) is an autosomal dominant disorder with various skeletal abnormalities occurring as part of a complex phenotype. Tibial dysplasia, which typically presents as anterolateral bowing of the leg with subsequent fracture and nonunion (pseudarthrosis), is a serious but infrequent osseous manifestation of NF1. Over the past several years, results from clinical and experimental studies have advanced our knowledge of the role of NF1 in bone. On the basis of current knowledge, we propose a number of concepts to consider as a theoretical approach to the optimal management of tibial pseudarthrosis.

METHODS

A literature review for both clinical treatment and preclinical models for tibial dysplasia in NF1 was performed. Concepts were discussed and developed by experts who participated in the Children's Tumor Foundation sponsored International Bone Abnormalities Consortium meeting in 2011.

RESULTS

Concepts for a theoretical approach to treating tibial pseudarthrosis include: bone fixation appropriate to achieve stability in any given case; debridement of the "fibrous pseudarthrosis tissue" between the bone segments associated with the pseudarthrosis; creating a healthy vascular bed for bone repair; promoting osteogenesis; controlling overactive bone resorption (catabolism); prevention of recurrence of the "fibrous pseudarthrosis tissue"; and achievement of long-term bone health to prevent recurrence.

CONCLUSIONS

Clinical trials are needed to assess effectiveness of the wide variation of surgical and pharmacologic approaches currently in practice for the treatment of tibial pseudarthrosis in NF1.

LEVEL OF EVIDENCE

Level V, expert opinion.

Experience with free fibula transfer with screw fixation as a primary modality of treatment for congenital pseudarthosis of tibia in children - Series of 26 cases

BACKGROUND

Congenital pseudarthrosis is one of the greatest challenges of paediatric orthopaedic practice. Treatment options and literature addressing this condition are numerous, reflecting the difficulty in management. We aimed to study the effectiveness of free fibula transfer as a primary modality of treatment in children with this condition in terms of achieving length, union, and normal axis of the involved leg.

MATERIALS AND METHODS

During the period of 2001 to 2010, 26 children with congenital pseudarthrosis of tibia between age group of 2-8 years were evaluated and were reconstructed using contra-lateral free fibula graft, and then patients were followed up for 5 years subsequently. Patients were examined and time of bony union, weight bearing ability and walking without support were noted. Any complication directly or indirectly related to surgery with any complication seen in the due course of follow up of 5 years was also taken care of.

RESULTS

In our experience with treatment of congenital pseudarthrosis over a span of 10 years with free fibula transfer, the results have been gratifying with no flap loss. All our patients had UNEVENTFUL post-op recovery. Only 2 patients out of 26 had non-union, for which cancellous bone grafting was done (7.6%). Most of the patients were ambulatory with support by 3-6 months and continued to walk without support after a span of 18-24 months. The incidence of stress fracture in our study over the follow-up period was 4 out of 26 pts (15.3%). None of them had any deformity in the donor leg.

CONCLUSION

When compared to other surgical modalities of treatment of the problem in question, vascularised free fibula transfer has emerged as a real saviour with good patient compliance and less complication rate in our study. It achieves the desired target with no residual deformities and near normal to normal gait with no stigma of bone removal from other leg.

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.

Treatment of long bone defects and non-unions: from research to clinical practice

The treatment of long bone defects and non-unions is still a major clinical and socio-economical problem. In addition to the non-operative therapeutic options, such as the application of various forms of electricity, extracorporeal shock wave therapy and ultrasound therapy, which are still in clinical use, several operative treatment methods are available. No consensus guidelines are available and the treatments of such defects differ greatly. Therefore, clinicians and researchers are presently investigating ways to treat large bone defects based on tissue engineering approaches. Tissue engineering strategies for bone regeneration seem to be a promising option in regenerative medicine. Several in vitro and in vivo studies in small and large animal models have been conducted to establish the efficiency of various tissue engineering approaches. Neverthelsss, the literature still lacks controlled studies that compare the different clinical treatment strategies currently in use. However, based on the results obtained so far in diverse animal studies, bone tissue engineering approaches need further validation in more clinically relevant animal models and in clinical pilot studies for the translation of bone tissue engineering approaches into clinical practice.

Early resection of congenital pseudarthrosis of the tibia and successful reconstruction using the Masquelet technique

Congenital pseudarthrosis of the tibia remains one of the most difficult orthopaedic problems. We describe early excision and the use of the Masquelet technique to reconstruct the bone defect in a child aged 14 months. Consolidation sufficient for complete weight-bearing was achieved by seven weeks. After two and a half years, the child was asymptomatic with a fully reconstructed tibia and no leg-length discrepancy.

Recent updates of surgical techniques and applications of free vascularized fibular graft in extremity and trunk reconstruction

Successful free vascularized bone transfers have revolutionized the limb salvage and musculoskeletal reconstruction. The free vascularized fibula remains the mainstay in bone reconstruction combines the benefits of blood supply, biological potential, and callus formation with its unique biomechanical characteristics offering a supreme candidate for various dissolvable issues. Especially in conditions where there was lack of other applicable method and the free vascularized fibular graft was introduced as the only alternative. Extensive traumatic bone loss, tumor resection, femoral head osteonecrosis and congenital defects have been managed with exceptional results beyond expectations. The present manuscript updates several issues in application of free vascularized fibular graft in extremity and trunk reconstruction. It also highlights tips and pearls of surgical technique in some crucial steps of harvesting the vascularized fibular graft in order to offer a vascularized bone with safety and low donor site morbidity.

Vascularized fibula transfer for lower limb reconstruction

Massive bony defects of the lower extremity are usually the result of high-energy trauma, tumor resection, or severe sepsis. Vascularized fibular grafts are useful in the reconstruction of large skeletal defects, especially in cases of scarred and avascular recipient sites, or in patients with combined bone and soft-tissue defects. Microvascular free fibula transfer is considered the most suitable autograft for reconstruction of the middle tibia because of its long cylindrical straight shape, mechanical strength, predictable vascular pedicle, and hypertrophy potential. The ability to fold the free fibula into two segments or to combine it with massive allografts is a useful technique for reconstruction of massive bone defects of the femur or proximal tibia. It can also be transferred with skin, fascia, or muscle as a composite flap. Proximal epiphyseal fibula transfer has the potential for longitudinal growth and can be used in the hip joint remodeling procedures. Complications can be minimized by careful preoperative planning of the procedure, meticulous intraoperative microsurgical techniques, and strict postoperative rehabilitation protocols. This literature review highlights the different surgical techniques, indications, results, factors influencing the outcome, and major complications of free vascularized fibular graft for management of skeletal or composite defects of the lower limb.

Free vascularised fibular graft for reconstruction of defects of the lower limb after resection of tumour

We describe a retrospective review of 38 cases of reconstruction following resection of the metaphysiodiaphysis of the lower limb for malignant bone tumours using free vascularised fibular grafts. The mean follow-up was for 7.6 years (0.4 to 18.4). The mean Musculoskeletal Tumor Society score was 27.2 (20 to 30). The score was significantly higher when the graft was carried out in a one-stage procedure after resection of the tumour rather than in two stages. Bony union was achieved in 89% of the cases. The overall mean time to union was 1.7 years (0.2 to 10.3). Free vascularised fibular transfer is a major operation with frequent, but preventable, complications which allows salvage of the limb with satisfactory functional results.

Congenital pseudarthrosis of the radius treated with gradual distraction and free vascularized fibular graft: case report

Only 18 cases of congenital radial pseudarthrosis have been reported in the English literature; of these, 4 have been treated with free vascularized fibular graft. We present a case of a 9-year-old female patient with neurofibromatosis type 1 who underwent gradual distraction through the pseudarthrosis site and subsequent vascularized fibular grafting for isolated congenital pseudarthrosis of her left radius and concomitant longitudinal and angular deformity of the wrist joint. At the last follow-up, 10 years postoperatively, the patient has maintained bony union, with full wrist flexion-extension and forearm pronation-supination.