Pedicled vascularized fibular graft with Ilizarov external fixator for reconstructing a large bone defect of the tibia after tumor resection

Treatment of large bone defects in load-bearing bone: traditional and novel bone grafts

Large bone defects in load-bearing bone can result from tumor resection, osteomyelitis, trauma, and other factors. Although bone has the intrinsic potential to self-repair and regenerate, the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge. Traditionally, repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites, and autogenous bone grafting remains the "gold standard" treatment. However, the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone, donor-site morbidities, and the risk of rejection. In recent years, the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes. In addition to osteoconductivity and osteoinductivity, optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects, but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength. A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements. In this review, the use of traditional bone grafts in load-bearing bone defects, as well as their advantages and disadvantages, is summarized and reviewed. Furthermore, we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance, structural, and functional bionics to provide ideas and directions for future research.

Comparison of orthofix external fixator combined with vascularized fibula graft versus single segmental femoral lengthening for treating femoral defects ≥ 6 cm: a retrospective study

BACKGROUND

Bone lengthening and free vascularized fibula graft (FVFG) represent two prevalent modalities for bone defect repair. The objective of this study was to compare the efficacy disparities between FVFG and single - segmental bone lengthening (BL) when the Orthofix external fixator was utilized in the treatment process.

METHODS

The follow - up data of 72 patients with femoral defects, who received treatment from January 2009 to May 2019, were collected for retrospective analysis. Among them, 60 comparable patients were stratified into two groups: one group of 30 patients received free vascularized fibular graft in combination with Orthofix external fixation (FVFG group), and the other group of 30 patients underwent single - segmental bone lengthening using the Orthofix external fixator (BL group). The specific aspects evaluated encompassed operation time, intraoperative blood loss, postoperative Activities of Daily Living (ADL) score, assessment by the Association for the Study and Application of the Method of Ilizarov (ASAMI), limb length discrepancy (LLD), external fixation index, bone union status, and complications.

RESULTS

1.Surgical - related indicators: The mean operation time in the FVFG group ( 5.04 ± 1.22 h) was significantly longer than that in the BL group (1.58 ± 0.56 h, p<0.001). The intraoperative blood loss (450 ± 190.73 ml) in the FVFG group was substantially higher than that in the BL group (120 ± 46.23 ml, p<0.01). Although the duration of external fixator use in the FVFG group (16.9 ± 3.52 months) was marginally longer than that in the BL group (15.53 ± 2.09 months), this difference did not reach statistical significance (p=0.073). 2.Postoperative complications: According to the Paley classification system, no significant differences were observed between the two groups in terms of nail infection, nail loosening, limb edema, nonunion (including nonunion in the BL group and fibula nonunion in the FVFG group), and postoperative fractures. All complications were effectively managed through appropriate treatment strategies. 3.Functional evaluation: Based on the ASAMI criteria, the excellent - to - good rate of bone outcomes in the FVFG group was 80.0%, while the BL group demonstrated superior results (p = 0.028). The excellent - to - good rate of limb function in the FVFG group was 36.6%, and there was no significant difference between the two groups (p = 0.537).

CONCLUSION

For the treatment of femoral defects measuring ≥ 6 cm, single - segmental bone lengthening with the Orthofix external fixator exhibited advantages in terms of shorter operation time and reduced blood loss compared to FVFG combined with the Orthofix external fixator. Although other outcomes were comparable between the two groups, FVFG demonstrated broader applicability across diverse bone defect classifications, primarily constrained by the defect length and the vascular condition of the recipient site.

Early Postoperative Weight Bearing Following the Reconstruction of Traumatic Complex Tibial Bone Defects by Vascularized Free Fibula and Ilizarov External Fixator: A Case Series

OBJECTIVE

Post-traumatic tibial bone defects represent a significant challenge to orthopedic surgeons. Various reconstructive methods are available based on associated local soft tissue injury and defect size. Free vascularized fibular graft represents a major successful technique; combined with a rigid Ilizarov external fixator, it allows safe, immediate postoperative weight bearing. In this article, we describe a series of six patients managed according to the previously presented plan, achieving satisfactory results.

METHODS

A series of six patients, all males with an average age of 33.3 years, underwent reconstruction for post-traumatic complex tibial bony defects using contralateral free vascularized fibular grafts and Ilizarov external fixation. Initially, all patients underwent multiple sessions of debridement and a simple pin-to-bar external fixator. The bony defect averaged 15 cm, and the average harvested length of the fibula used for reconstruction was 22.1 cm. All patients started immediate total weight bearing postoperatively, with a mean time of 17 days after bony union Ilizarov was replaced with minimally invasive plate osteosynthesis (MIPO) in all patients, and continued full weight bearing (FWB).

RESULTS

During the follow-up period, averaging 19.3 months, all patients achieved bony union with a mean time of 3.75 months. Patients spent an average of 6.4 months in the Ilizarov frame before it was replaced with MIPO; graft hypertrophy occurred in all patients, averaging 52.6%.

CONCLUSION

The combined use of a vascularized fibular bone graft and an Ilizarov frame proves to be a successful and safe approach for immediate postoperative FWB. This yields comparable outcomes in terms of union and function.

Comparison of free vascularized fibular grafts and the Masquelet technique for the treatment of segmental bone defects with open forearm fractures: a retrospective cohort study

PURPOSE

Severe open forearm fractures commonly involve segmental bone defects. Although several methods have been proposed to treat segmental bone defects with such fractures, research comparing the radiological and clinical outcomes of free vascularized fibular grafts (FVFG) and the Masquelet technique (MT) is rare.

METHODS

Data on 43 patients with open forearm fractures and segmental bone defects treated surgically in our hospital from January 2005 to January 2021 were retrospectively analyzed, and these patients were divided into an FVFG group (18 cases) and an MT group (25 cases). Clinical and radiological evaluations were performed regularly, and the minimum follow-up was 18 months.

RESULTS

All 43 patients were followed up for 18 to 190 months, with a mean of 46.93 months. The mean follow-up time was significantly longer in the FVFG group than in the MT group (p = 0.000). Bone healing time was 3-16 months, with a mean of 4.67 months. The QuickDASH score at the last follow-up was 0-38.6, with a mean of 17.71, and there was no statistically significant difference between the two groups. Operative time, hospital stay, and intraoperative bleeding for bone defect reconstruction were higher in the FVFG group compared to the MT group (p = 0.000), whereas the number of procedures was lower in the FVFG group than in the MT group (p = 0.035).

CONCLUSIONS

FVFG and the MT showed satisfactory clinical results for segmental bone defects of the forearm. Compared with FVFG, the MT exhibited a lower operative time, hospital stay, and intraoperative bleeding.

LEVEL OF EVIDENCE

Level IV. Trial registration This study was registered in the Chinese Clinical Trial Registry (registration no. ChiCTR2300067675; registered 17 January 2023), https://www.chictr.org.cn/showproj.html?proj=189458 .

Current application and future perspectives of antimicrobial degradable bone substitutes for chronic osteomyelitis

Chronic osteomyelitis remains a persistent challenge for the surgeons due to its refractory nature. Generally, treatment involves extensive debridement of necrotic bone, filling of dead space, adequate antimicrobial therapy, bone reconstruction, and rehabilitation. However, the optimal choice of bone substitute to manage the bone defect remains debatable. This paper reviewed the clinical evidence for antimicrobial biodegradable bone substitutes in the treatment of osteomyelitis in recent years. Indeed, this combination was proved to eradicate infection and facilitate bone reconstruction, which might reduce the cost and hospital stay. Handling was associated with increased risk of unwanted side effect to affect bone healing. The study provides some valuable insights into the clinical evaluation of treatment outcomes in the aspects of infection eradication, bone reconstruction, and complications caused by materials. However, achieving complete infection eradication and subsequently perfect bone reconstruction remains challenging in compromised conditions, hence advanced innovative bone substitutes are imperative. In this review, we mainly focus on the desired functional effects of advanced bone substitutes on infection eradication and bone reconstruction from the future perspective. Handling property was optimized to simplify surgery process. It is expected that this review will provide an important opportunity to enhance the understanding of the design and application of innovative biomaterials to synergistically eradicate infection and restore integrity and function of bone.

Reconstruction of Intercalary Bone Defects After Tumour Resection with the Use of a Free Vascularised Fibular Graft: the Concealed Advantages of the External Fixator

The free vascularised fibular graft represents the mainstay of intercalary bone defect reconstruction after tumour resection. Different reconstruction techniques are described, favouring internal fixation and possibly overlooking potential advantages of external fixation. This series is a description of the technique performed at our institution using an external fixator for the reconstruction of segmental bone defects which enables to maintain limb length and rotational alignment after large segmental bone resection. Data collected were demographic, surgical and histological data, perioperative complications and postoperative data. Eighteen different complications were encountered in seven patients. Mean reoperation rate was 1.3 per patient but no patient required further interventions in order to correct limb length or rotational alignment. Pin-track infection rate was 6%. The limb salvage rate was 100%. Solid final bone healing was obtained in all patients. External fixation for the reconstruction of intercalary bone defects after tumour resection is a safe technique which might offer the advantage of limb length and alignment preservation.

Use of Three-Column Reconstruction and Free Vascularized Fibular Grafts for the Repair of Large Tibial Defects after Tumor Resection

Background

This study aimed to evaluate the clinical outcomes of three-column reconstruction of the lower leg using a single-barrel contralateral vascularized fibular graft (VFG), medial locking plate, and the ipsilateral fibula for the repair of large tibial defects after tumor resection.

Methods

In this retrospective study, we reviewed 12 patients who underwent three-column reconstruction using a single-barrel contralateral VFG, medial locking plate, and the ipsilateral fibula between June 1996 and May 2020. These patients had large tibial bone defects following tumor resection. The mean age of the patients was 26.3 years (range, 11-63 years), and 7 of them were women. The mean follow-up period was 104.8 months (range, 26-284 months). The mean size of the tibial bone defect after tumor resection was 17.8 cm (range, 11-26.8 cm). The clinical and radiological outcomes were evaluated at the final follow-up.

Results

All patients survived beyond the final follow-up without recurrence of the primary bone tumor. The mean time from reconstruction to bony union at both host-graft junctions was 12.9 months (range, 4-36 months). The mean Musculoskeletal Tumor Society score was 82.3% (range, 60%-97%). All tibial defects were reconstructed with adequate bone healing. There were 4 cases of stress fracture and graft failure; these were resolved by using longer plates and more screws. All patients were ambulatory without assistance and showed no permanent complications.

Conclusions

Large tibial defects that occur after tumoral resection can be effectively reconstructed by three-column reconstruction using a medial locking plate, an inlay single-barrel VFG harvested from the contralateral side, and the intact ipsilateral fibula. This technique permits early weight-bearing before fibular hypertrophy and bony union.

Lower leg reconstruction after resection of a squamous cell carcinoma on necrobiosis lipoidica with a pedicled fibula and an extended anterolateral thigh flap-a case report

BACKGROUND

Extensive loss of soft tissue and bone due to neoplasia, trauma, or infection in extremities often leads to amputation.

CASE PRESENTATION

We present the case of a 72-year-old female patient presenting with an extended cutaneous squamous cell carcinoma of the lower leg, developed on top of necrobiosis lipoidica. After achieving the R0 resection, a 26 × 20-cm soft tissue and 15-cm tibial bone defect resulted. The contralateral leg had been lost due to the same disease 18 years before. We achieved a successful reconstruction of the leg using a pedicled fibula transplantation, an extended anterolateral thigh perforator flap, and an internal fixation with plate and screws. Two years after the original surgery, the patient is relapse-free and mobile, with adequate function of the reconstructed foot.

CONCLUSIONS

Our case presented a unique combination of pedicled fibula transplantation and free extended ALT perforator flap to reconstruct an extensive defect after resection of a rare cSCC on top of NL. In selected cases, the boundaries of limb salvage can be pushed far beyond the current standards of treatment.

Clinical outcomes of bone transport using rail fixator in the treatment of femoral nonunion or bone defect caused by infection

Purpose

The rail fixator can improve the treatment outcome and provide good stability in patients with femoral bone transport. The purpose of this study is to investigate the clinical outcomes of bone transport using the Ilizarov technique by rail fixator in the treatment of femoral nonunion or bone defects caused by infection.

Methods

Clinical feature and treatment outcomes of 32 consecutive adult patients with femoral nonunion or bone defect caused by infection from January 2012 to January 2019 at a minimum of 2 years of follow-ups were retrospectively analyzed. Data were collected on participants' demographic details. All difficulties related to bone transport were documented according to Paley's classification. The clinical outcomes were evaluated using ASAMI criteria at the last clinical visit.

Results

All 32 patients with an average follow-up of 33.5 months. There were 17 problems, 21 obstacles, and 8 complications, and the complication rate per patient was 1.4. The main complications were pin-site infection (53.1%), axial deviation (21.9%), joint stiffness (18.8%), the delayed union of the docking site (18.8%), soft tissue incarceration(15.6%), delayed consolidation(6.3%), malunion(6.3%), and refracture (3.1%). All the patients achieved bone union, and no recurrence of infection was observed. The excellent and good rates of ASAMI bone and functional results were 87.5% and 81.3%, respectively.

Conclusion

Bone transport using the Ilizarov technique is an effective method for the treatment of femoral nonunion or bone defect caused by infection, and rail fixators have obtained satisfactory results in terms of bone and functional results.

Vascularized fibular grafts for the treatment of long bone defects: pros and cons. A systematic review and meta-analysis

PURPOSE

To quantify union rate, complication rate, reintervention rate, as well as functional outcome after vascularized fibular bone grafts (VFGs) for the treatment of long-bone defects.

METHODS

A comprehensive search was performed in the PubMed, Web of Science, and Cochrane databases up to August 18, 2020. Randomized controlled trials, comparative studies, and case series describing the various techniques available involving VFGs for the reconstruction of segmental long-bone defects were included. A meta-analysis was performed on union results, complications, and reinterventions. Assessment of risk of bias and quality of evidence was performed with the Downs and Black's "Checklist for Measuring Quality".

RESULTS

After full-text assessment, 110 articles on 2226 patients were included. Among the retrieved studies, 4 were classified as poor, 83 as fair, and 23 as good. Overall, good functional results were documented and a union rate of 80.1% (CI 74.1-86.2%) was found, with a 39.4% (CI 34.4-44.4%) complication rate, the most common being fractures, non-unions and delayed unions, infections, and thrombosis. Donor site morbidity represented 10.7% of the total complications. A 24.6% reintervention rate was documented (CI 21.0-28.1%), and 2.8% of the patients underwent amputation.

CONCLUSIONS

This systematic review and meta-analysis documented good long-term outcomes both in the upper and lower limb. However, VFG is a complex and demanding technique; this complexity means an average high number of complications, especially fractures, non-unions, and vascular problems. Both potential and limitations of VFG should be considered when choosing the most suitable approach for the treatment of long-bone defects.

Ilizarov Bone Transfer for Treatment of Large Tibial Bone Defects: Clinical Results and Management of Complications

BACKGROUNDS

The purpose of this study is to present our clinical experience using the Ilizarov bone transfer technique and free-flap technique in the reconstruction of large tibial bone and soft tissue defects, including an evaluation of both the management of postoperative complications and long-term outcomes.

METHODS

From January 2010 to May 2020, 72 patients with tibia bone and soft tissue defects were retrospectively evaluated. Either an anterolateral thigh perforator flaps (ALTP) or latissimus dorsi musculocutaneous flaps (LD), solely or in combination, were used to cover soft tissue defects. Once the flap was stabilized, an Ilizarov external fixator was applied to the limb. Follow-up was postoperatively performed at 1, 3, 6, 9, and 12 months.

RESULTS

Postoperatively, there were two cases of total and five of partial flap necrosis, and two cases of subcutaneous ulcers, which were caused by vascular crisis, infection, and hematoma, respectively. All the patients underwent Ilizarov external fixator surgery after flap recovery. A total of 16 complications occurred, including 3 cases of simple needle tract infection (antibiotic treatment) and 13 cases of complications requiring reoperation. A correlation factor analysis revealed that the main factors affecting the healing time were the defect length and operative complications. All patients with complications treated with the vascularized iliac flap eventually healed completely.

CONCLUSIONS

The Ilizarov method used together with an ALTP, LD, or a combination thereof yields good clinical results for repairing large bone and soft tissue defects of the tibia, thus reducing the incidence of amputations. However, longer treatment times may be involved, and postoperative complications can occur. The vascularized iliac flap may be a suitable choice for the treatment of postoperative complications of this type of Ilizarov bone transport.

Reconstruction of traumatic tubular bone defects using vascularized fibular graft

Large segmental bone defects due to major trauma constitute a major challenge for the orthopaedic surgeon, especially when combined with poor or lost soft tissue envelope. Vascularized fibular transfer is considered as the gold standard for the reconstruction of such defects of the extremities due to its predictable vascular pedicle, long cylindrical shape, and tendency to hypertrophy, and resistance to infection. Vascularized bone grafts remain viable throughout the healing period and are capable of inducing rapid graft union without prolonged creeping substitution, osteogenesis and hypertrophy at the reconstruction site, and fight with infection. The fibular graft can be transferred solely, or as a composite flap including muscle, subcutaneous tissue, skin and even a nerve segment in order to reconstruct both bone and soft tissue components of the injury at single stage operation. Such a reconstruction can even be performed in the presence of local infection, since vascularized bone and adjacent soft tissue components enhances the blood flow at the traumatized zone, allowing for the delivery of antibiotics and immune components to the infection site. In an effort to preserve growth potential in pediatric patients; the fibular head and proximal growth plate can be included to the graft. This practice also enables to reconstruct the articular ends of various bones, including distal radius and proximal ulna. Apart from defect reconstruction, vascularized fibular grafts also proved to be a reliable in treating atrophic nonunions, reconstruction of osteomyelitic bone segments. These grafts are superior to alternative reconstructive techniques, as bone grafts with intrinsic blood supply lead to higher success rates in reconstruction and accelerate the repair process at the injury site in cases where blood supply to the injury zone is defective, poor soft tissue envelope, and local infection at the trauma zone.

Investigation of a Prevascularized Bone Graft for Large Defects in the Ovine Tibia

In vivo bioreactors are a promising approach for engineering vascularized autologous bone grafts to repair large bone defects. In this pilot parametric study, we first developed a three-dimensional (3D) printed scaffold uniquely designed to accommodate inclusion of a vascular bundle and facilitate growth factor delivery for accelerated vascular invasion and ectopic bone formation. Second, we established a new sheep deep circumflex iliac artery (DCIA) model as an in vivo bioreactor for engineering a vascularized bone graft and evaluated the effect of implantation duration on ectopic bone formation. Third, after 8 weeks of implantation around the DCIA, we transplanted the prevascularized bone graft to a 5 cm segmental bone defect in the sheep tibia, using the custom 3D printed bone morphogenic protein 2 (BMP-2) loaded scaffold without prior in vivo bioreactor maturation as a control. Analysis by micro-computed tomography and histomorphometry found ectopic bone formation in BMP-2 loaded scaffolds implanted for 8 and 12 weeks in the iliac pouch, with greater bone formation occurring after 12 weeks. Grafts transplanted to the tibial defect supported bone growth, mainly on the periphery of the graft, but greater bone growth and less soft tissue invasion was observed in the avascular BMP-2 loaded scaffold implanted directly into the tibia without prior in vivo maturation. Histopathological evaluation noted considerably greater vascularity in the bone grafts that underwent in vivo maturation with an inserted vascular bundle compared with the avascular BMP-2 loaded graft. Our findings indicate that the use of an initial DCIA in vivo bioreactor maturation step is a promising approach to developing vascularized autologous bone grafts, although scaffolds with greater osteoinductivity should be further studied. Impact statement This translational pilot study aims at combining a tissue engineering scaffold strategy, in vivo prevascularization, and a modified transplantation technique to accelerate large segmental bone defect repair. First, we three-dimensional (3D) printed a 5 cm scaffold with a unique design to facilitate vascular bundle inclusion and osteoinductive growth factor delivery. Second, we established a new sheep deep circumflex iliac artery model as an in vivo bioreactor for prevascularizing the novel 3D printed osteoinductive scaffold. Subsequently, we transplanted the prevascularized bone graft to a clinically relevant 5 cm segmental bone defect in the sheep tibia for bone regeneration.

Highly Cancellous Titanium Alloy (TiAl6V4) Surfaces on Three-Dimensionally Printed, Custom-Made Intercalary Tibia Prostheses: Promising Short- to Intermediate-Term Results

Custom-made, three-dimensionally-printed (3D) bone prostheses gain increasing importance in the reconstruction of bone defects after musculoskeletal tumor resections. They may allow preservation of little remaining bone stock and ensure joint or limb salvage. However, we believe that by constructing anatomy-imitating implants with highly cancellous titanium alloy (TiAl₆V₄) surfaces using 3D printing technology, further benefits such as functional enhancement and reduction of complications may be achieved. We present a case series of four patients reconstructed using custom-made, 3D-printed intercalary monobloc tibia prostheses treated between 2016 and 2020. The mean patient age at operation was 30 years. Tumor resections were performed for Ewing sarcoma (n = 2), high-grade undifferentiated pleomorphic bone sarcoma (n = 1) and adamantinoma (n = 1). Mean resection length was 17.5 cm and mean operation time 147 min. All patients achieved full weight-bearing and limb salvage at a mean follow-up of 21.25 months. One patient developed a non-union at the proximal bone-implant interface. Alteration of implant design prevented non-union in later patients. Mean MSTS and TESS scores were 23.5 and 88. 3D-printed, custom-made intercalary tibia prostheses achieved joint and limb salvage in this case series despite high, published complication rates for biological and endoprosthetic reconstructions of the diaphyseal and distal tibia. Ingrowth of soft tissues into the highly cancellous implant surface structure reduces dead space, enhances function, and appears promising in reducing complication rates.

Osteoinductive 3D printed scaffold healed 5 cm segmental bone defects in the ovine metatarsus

Autologous bone grafts are considered the gold standard grafting material for the treatment of nonunion, but in very large bone defects, traditional autograft alone is insufficient to induce repair. Recombinant human bone morphogenetic protein 2 (rhBMP-2) can stimulate bone regeneration and enhance the healing efficacy of bone grafts. The delivery of rhBMP-2 may even enable engineered synthetic scaffolds to be used in place of autologous bone grafts for the treatment of critical size defects, eliminating risks associated with autologous tissue harvest. We here demonstrate that an osteoinductive scaffold, fabricated by combining a 3D printed rigid polymer/ceramic composite scaffold with an rhBMP-2-eluting collagen sponge can treat extremely large-scale segmental defects in a pilot feasibility study using a new sheep metatarsus fracture model stabilized with an intramedullary nail. Bone regeneration after 24 weeks was evaluated by micro-computed tomography, mechanical testing, and histological characterization. Load-bearing cortical bridging was achieved in all animals, with increased bone volume observed in sheep that received osteoinductive scaffolds compared to sheep that received an rhBMP-2-eluting collagen sponge alone.

Managing bone loss in open fractures

Segmental bone loss continues to pose substantial clinical and technical challenges to orthopaedic surgeons. While several surgical options exist for the treatment of these complex patients, there is not a clear consensus or specific guidelines on the optimal management of these injuries as a whole. Many factors must be taken into consideration when planning surgery for these individuals. In order for these techniques to yield optimal results, each injury must be approached in a step-wise and multidisciplinary fashion to ensure that care is taken in bone and wound bed preparation, that soft tissues are healthy and free of contaminants, and that the patient's medical condition has been optimized. Through this article, we will answer relevant questions and discuss common obstacles and challenges encountered with these complex injuries. We will also review the many treatment options available or in development to address this problem.

Limb salvage for malignant bone tumours of distal tibia with dual ipsilateral vascularized autogenous fibular graft in a trapezoid-shaped array with ankle arthrodesis and preserving subtalar joint

BACKGROUND

The treatment of malignant tumours of the distal tibia is a challenging surgical problem due to the scarce soft tissue coverage and the instability of the ankle joint that often occurs after resection. However, there is no consensus on the ideal treatment for malignant tumours of the distal tibia.

METHODS

We report a new reconstruction for five patients with high-grade osteosarcoma of distal tibia, using dual ipsilateral vascularized autogenous fibular graft in a trapezoid-shaped array and external fixator, with ankle arthrodesis and preserving subtalar joints. The patients were examined clinically and radiographically.

RESULTS

The average follow-up duration was 88 months. The mean wound healing time was 14 days. Bone healing was achieved for all the five patients at an average time of 7 months. There were no complications of mal-union, skin necrosis, post-operative infection, loss of internal fixation, peroneal nerve injury. One patient had a local recurrence, which required amputation 15 months postoperatively. The remaining four patients were able to walk with an average functional score of 81.25% according to MSTS.

CONCLUSIONS

Our study shows that this technique is safe and effective to perform implantation of dual ipsilateral vascularized autogenous fibular graft in a trapezoid-shaped array and preserving subtalar joints in terms of the distal tibial reconstruction for malignant bone tumour of the distal tibia. This reconstruction represents a biological alternative protocol for limb salvage in cases of malignant bone tumour of the distal tibia, with encouraging results and with the advantages of lower complications and accelerating recovery.

LEVEL OF EVIDENCE

Level IV.

One-Barrel Microsurgical Fibula Flap for Reconstruction of Large Defects of the Femur

Various methods for reconstructing large femur bone defects after tumor resection have been introduced. In this study, we reviewed the clinical outcomes of using a 1-barrel free vascularized fibular graft (FVFG) protected by a lateral locking plate for large femoral defects not involving the knee joint.Between August 2007 and August 2013, we treated 7 patients with large femoral bone defects after tumor resection. The mean age of the patients was 19 years (range, 12-36 years), and 3 were women. All defects were free of infection before the procedure. Femoral bone defects were reconstructed using a 1-barrel FVFG protected by a lateral locking plate. The mean bone defect size was 10.5 cm (range, 6-16 cm). We reviewed clinical outcomes at the last follow-up.All patients survived beyond the last follow-up; the mean follow-up period was 54 months (range, 26-100 months). Two patients sustained stress fractures of the FVFG, but the lateral locking plate protected the fractured graft until in situ bone healing obtained. Mean time to bone union of both host-graft junctions was 24 months (range, 18-31 months). The mean Musculoskeletal Tumor Society score (%) was 85.8% (range, 80-95%).A 1-barrel FVFG protected by a lateral locking plate maintained a stable graft-host bone construct, successfully leading to bone healing, even in cases of stress fractures of the graft, and appears to be a good option for large femur bone defects.

[Progress in repair and reconstruction of large segmental bone tumor defect in distal tibia]

Objective

To review the methods of repair and reconstruction of the large segmental bone tumor defect in distal tibia.

Methods

The related literature of repair and reconstruction of the large segmental bone tumor defect in disatal tibia were reviewed and analyzed from the aspects of the reserved ankle joint and the non-reserved ankle joint.

Results

The large segmental bone tumor defect in distak tibia is not rare in clinical. In addition to conventional allograft bone transplantation, vascularized autologous fibular transplantation, vascularized fibular allograft, inactivated tumor regeneration, distraction osteogenesis, and bone transport techniques; membrane-induced osteogenesis, artificial tumor stem prosthesis, three-dimensional printed metal trabecular prosthesis, ankle arthrodesis, artificial tumor ankle joint placement surgery are now gradually applied to the repair and reconstruction of large segmental bone defects in the distal tibia. Moreover, due to its long survival time, the function of reconstruction of the bone tumor defect in the distal tibia has also received increasing attention.

Conclusion

Although the ideal methods of repair and reconstruction of the large segmental bone tumor defect in the distal tibia has not yet been developed, great progress has been achieved. Recently, with the appearance of three-dimensional printing and various preoperative simulation techniques, personalized and precise therapy could become ture, but therapies for the large segmental bone tumor defect in the distal tibia still need to be further explored.

RECONSTRUCTION OF BONE DEFECTS AFTER TUMOR RESECTION BY AUTOAND ALLOGRAFTS (review of literature)

The problem of replacement of large bone defects resulting from segmental bone resections in patients with bone tumors is still actual in modern orthopedics. Segmental defects cause the main difficulty especially in cases of disturbance of normal biomechanics while the “gold standard” of reconstruction with bone autograft is not always possible. The reason is that the defect can be so extensive that would make it impossible to harvest necessary autobone stock. Therefore, allografts based on demineralized bone with optimal properties for osteoregeneration are used as an alternative for autograft. For certain composite materials it is possible to program the properties of future graft by changing its compound. Literature analysis revealed that the effectiveness of the allograft in combination with additional components is comparable to autograft effectiveness. Mesenchymal stem cells of both bone marrow and adipose tissue can be used as an additional component to improve osteoregeneration. It is noteworthy that the analyzed studies did not reveal the influence of stem cells on the tumor recurrence. Nevertheless, the authors support the need of further researches in this area to confirm gained results. Some authors still prefer traditional methods of bone traction despite obtaining own satisfactory results of defects reconstruction with allografts. Such opinion is based on proven effectiveness of the method, structural stability of construction during treatment period and ability to adjust the process of bone regeneration at any stage. The authors goal was to analyze publications over the recent 5 years with the results of experiments and clinical studies on the replacement of large bone defects after bone tumor resection with autoand allografts. Based on the literature analysis the authors propose a general algorithm for graft selection in replacement of large bone defects after segmental bone resections. 

Management of post-traumatic bone defects of the tibia using vascularised fibular graft combined with Ilizarov external fixator

INTRODUCTION

Post-traumatic bone defects of the tibia present a difficult reconstructive challenge. Various methods of reconstruction are available, such as allografts, vascularised fibular graft (either free or pedicled) and bone transport technique.

PATIENTS AND METHODS

Fourteen patients with an average age of 34.1 years at operation (range, 12-65) with post-traumatic bony defects of the tibia were selected for reconstruction with vascularised fibular graft combined with Ilizarov external fixation. There were 12 male and two female. The size of the bony gap was 10.4 cm (range, 7-13) and the average length of the fibula used was 16.4 cm (range, 14-21).

RESULTS

The mean follow up period was 20.4 months (range, 10-37). All patients had bony union at both proximal and distal ends of the fibula primarily except one patient that required secondary iliac bone graft at the distal end of the fibula to obtain union. The average time for bone healing was 3.9 months (range, 3-9). The average time spent in Ilizarov frame was 5.9 months (range, 5-11). Unprotected full weight-bearing was achieved within an average of 7.3 months (range, 6-12).

CONCLUSION

Vascularised fibular bone graft combined with an Ilizarov frame is a successful approach to safely and effectively reconstruct bone defects of the tibia. It has the advantages of vascularised fibular bone grafts together with the biomechanical advantages of Ilizarov frame that allows weight bearing to start almost immediately after surgery. This leads to a good outcome regarding the union and function.

Vascularization in bone tissue engineering constructs

Vascularization of large bone grafts is one of the main challenges of bone tissue engineering (BTE), and has held back the clinical translation of engineered bone constructs for two decades so far. The ultimate goal of vascularized BTE constructs is to provide a bone environment rich in functional vascular networks to achieve efficient osseointegration and accelerate restoration of function after implantation. To attain both structural and vascular integration of the grafts, a large number of biomaterials, cells, and biological cues have been evaluated. This review will present biological considerations for bone function restoration, contemporary approaches for clinical salvage of large bone defects and their limitations, state-of-the-art research on the development of vascularized bone constructs, and perspectives on evaluating and implementing novel BTE grafts in clinical practice. Success will depend on achieving full graft integration at multiple hierarchical levels, both between the individual graft components as well as between the implanted constructs and their surrounding host tissues. The paradigm of vascularized tissue constructs could not only revolutionize the progress of BTE, but could also be readily applied to other fields in regenerative medicine for the development of new innovative vascularized tissue designs.