Reconstruction of Segmental Bone Defect in Canine Tibia Model Utilizing Bi-Phasic Scaffold: Pilot Study.

The reunion and restoration of large segmental bone defects pose significant clinical challenges. Conventional strategies primarily involve the combination of bone scaffolds with seeded cells and/or growth factors to regulate osteogenesis and angiogenesis. However, these therapies face inherent issues related to immunogenicity, tumorigenesis, bioactivity, and off-the-shelf transplantation. The biogenic micro-environment created by implanted bone grafts plays a crucial role in initiating the bone regeneration cascade. To address this, a highly porous bi-phasic ceramic synthetic bone graft, composed of hydroxyapatite (HA) and alumina (Al), was developed. This graft was employed to repair critical segmental defects, involving the creation of a 2 cm segmental defect in a canine tibia. The assessment of bone regeneration within the synthetic bone graft post-healing was conducted using scintigraphy, micro-CT, histology, and dynamic histomorphometry. The technique yielded pore sizes in the range of 230-430 µm as primary pores, 40-70 µm as secondary inner microchannels, and 200-400 nm as tertiary submicron surface holes. These three components are designed to mimic trabecular bone networks and to provide body fluid adsorption, diffusion, a nutritional supply, communication around the cells, and cell anchorage. The overall porosity was measured at 82.61 ± 1.28%. Both micro-CT imaging and histological analysis provided substantial evidence of robust bone formation and the successful reunion of the critical defect. Furthermore, an histology revealed the presence of vascularization within the newly formed bone area, clearly demonstrating trabecular and cortical bone formation at the 8-week mark post-implantation.

Comparison of the Translational Potential of Human Mesenchymal Progenitor Cells from Different Bone Entities for Autologous 3D Bioprinted Bone Grafts.

Reconstruction of segmental bone defects by autologous bone grafting is still the standard of care but presents challenges including anatomical availability and potential donor site morbidity. The process of 3D bioprinting, the application of 3D printing for direct fabrication of living tissue, opens new possibilities for highly personalized tissue implants, making it an appealing alternative to autologous bone grafts. One of the most crucial hurdles for the clinical application of 3D bioprinting is the choice of a suitable cell source, which should be minimally invasive, with high osteogenic potential, with fast, easy expansion. In this study, mesenchymal progenitor cells were isolated from clinically relevant human bone biopsy sites (explant cultures from alveolar bone, iliac crest and fibula; bone marrow aspirates; and periosteal bone shaving from the mastoid) and 3D bioprinted using projection-based stereolithography. Printed constructs were cultivated for 28 days and analyzed regarding their osteogenic potential by assessing viability, mineralization, and gene expression. While viability levels of all cell sources were comparable over the course of the cultivation, cells obtained by periosteal bone shaving showed higher mineralization of the print matrix, with gene expression data suggesting advanced osteogenic differentiation. These results indicate that periosteum-derived cells represent a highly promising cell source for translational bioprinting of bone tissue given their superior osteogenic potential as well as their minimally invasive obtainability.

Induced Membrane Technique of Masquelet; A Viable Option in Treatment of Post-Trauma Segmental Bone Loss: A Case Report.

In trauma and orthopaedic practice, the management of segmental bone loss constitutes a major challenge to the surgeon. Several methods have been employed in bone reconstruction with varying objectives depending on the size of the defect in question. A gap of not more than 2cm may benefit from acute docking and fixation, 4cm gap can be managed by non-vascularized structural or non-structural graft with fixation. Gaps of more than 4cm can be managed by numerous options which include allograft, vascularized structural graft and distraction osteogenesis with either linear rail system (LRS) or Ilizarov device. Masquelet technique of induced membrane formation is used to bridge a gap of more than 5cm and up to 25cm using bone cement as a spacer in first stage and use of autologous cancellous bone graft in the second stage.

En traumatologie et en orthopédie, la prise en charge de la perte osseuse segmentaire constitue un défi majeur pour la chirurgien. Plusieurs méthodes ont été employées dans la reconstruction d'os avec des objectifs variables en fonction de la taille du défaut en question. Un écart de pas plus de 2 cm peut en bénéficier de l'amarrage et de la fixation aigus, un écart de 4 cm peut être géré par structurelle non vascularisée ou greffe non structurelle avec fixation. Les espaces de plus de 4 cm peuvent être gérés par de nombreux options qui incluent allogreffe, greffe structurelle vascularisée et ostéogenèse par distraction avec l'un ou l'autre des systèmes de rails linéaires (LRS) ou appareil Ilizarov. Technique de Masquelet d'induit la formation de la membrane est utilisée pour combler un espace de plus de 5 cm et jusqu'à 25 cm en utilisant du ciment osseux comme espaceur dans la première étape et l'utilisation d'une greffe d'os spongieux autologue dans la deuxième étape. Mots clés: Défaut osseux segmentaire, ostéogenèse par distraction, technique de membrane induite, espaceur de ciment osseux.

Bilayer nanostructure coated AZ31 magnesium alloy implants: in vivo reconstruction of critical-sized rabbit femoral segmental bone defect.

Healing or reconstruction of critical-sized bone defects is still challenging in orthopaedic practice. In this study, we developed a new approach to control the degradation and improve the bone regeneration of the AZ31 magnesium substrate, fabricated as mesh cage implants. Subsequently, bilayer nanocomposite coating was carried out using polycaprolactone (PCL) and nano-hydroxyapatite (nHA) by dip-coating and electrospinning. Lastly, the healing capacity of the implants was studied in New Zealand White (NZW) rabbit critical-sized femur bone defects. X-ray analysis showed the coated implant group bridged and healed the critical defects 100% during four weeks of post-implantation. Micro-computed tomography (Micro-CT) study showed higher total bone volume (21.10%), trabecular thickness (0.73), and total porosity (85.71%) with bilayer coated implants than uncoated. Our results showed that nanocomposite coated implants controlled the in vivo degradation and improved bioactivity. Hence, the coated implants can be used as a promising bioresorbable implant for critical segmental bone defect repair applications.

Successful fifth metatarsal bulk autograft reconstruction of thermal necrosis post intramedullary fixation.

Reamed intramedullary (IM) screw fixation for proximal fifth metatarsal fractures is technically challenging with potentially devastating complications if basic principles are not followed. A case of an iatrogenic fourth-degree burn after elective reamed IM screw fixation of a proximal fifth metatarsal fracture in a high-level athlete is reported. The case was complicated by postoperative osteomyelitis with third-degree soft-tissue defect. This was successfully treated with staged autologous bone graft reconstruction, tendon reconstruction, and local bi-pedicle flap coverage. The patient returned to competitive-level sports, avoiding the need for fifth ray amputation. Critical points of the IM screw technique and definitive reconstruction are discussed. Bulk autograft reconstruction is a safe and effective alternative to ray amputation in segmental defects of the fifth metatarsal.Level of evidence V.

Use of a Reverse Metacarpal Bone Flap for the Treatment of Segmental Bone Defects of the Proximal Phalanges.

PURPOSE: The purpose of this retrospective study was to report the results of reconstruction of segmental bone defects of the proximal phalanges using a reverse metacarpal vascularized bone flap harvested from the third metacarpal bone. METHODS: From August 2012 to May 2017, 17 patients with segmental osteomyelitis or necrotic bone of the proximal phalanges were treated. There were 15 male and 3 female patients, with a mean age of 36 years (range, 19-65 years). The mean size of bone defects was 26 × 9 × 9 mm (range, 16 × 6 × 7 mm to 35 × 10 × 7 mm); and the mean size of bone flaps was 27 × 8 × 7 mm (range, 15 × 7 × 4 mm to 40 × 8 × 7 mm). RESULTS: The mean follow-up period was 26 months. The mean motion arc of the metacarpophalangeal joints was 56° (range, 22°-90°). The mean pinch strength of the injured fingers was 3.1 kg (range, 2-3.6 kg), and the mean pinch strength of the normal contralateral side was 6.9 kg (range, 4.2- 8.5 kg). CONCLUSIONS: The reverse metacarpal bone flap may promote osseous healing in reconstructing segmental defects of the proximal phalanges. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Surface Properties and MC3T3-E1 Cell Response of Cortical Bone Allografts Modified with Low-Concentration Phosphoric Acid.

BACKGROUND/AIMS: This experimental study aimed to evaluate the effect of low-concentration phosphoric acid on the surface structure of cortical allografts. METHODS: Allogenic cortical bones were obtained from femurs and tibias of New Zealand white rabbits. The bones were modified by treatment with various concentrations of phosphoric acid (10%, 20% or 30%) for 10, 30 or 60 minutes, then evaluated by the following methods: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and LIVE/DEAD assay, alkaline phosphatase (ALP) assay, biomechanical properties testing, contact angle detection, quantitative real-time polymerase chain reaction (Q-PCR), western blotting and scanning electron microscopy (SEM). RESULTS: Compared with the other groups, the group modified with 10% H3PO4 for 10 minutes had lower cytotoxicity according to MTT and LIVE/DEAD assays, higher hydrophilicity in the contact angle detection test and greater stability in the biomechanical properties test. Moreover, an up-regulation of osteopontin (OPN) in bones modified with 10% H3PO4 was observed by Q-PCR and western blotting. In addition, ALP assay and SEM showed that surface porosity and osteoinductivity were increased in the group modified with 10% H3PO4. CONCLUSIONS: Low-concentration phosphoric acid may be a potential method for surface modification of cortical allografts. Further animal experiments and animal infection model studies are required to validate the efficacy of surface-modified cortical allografts to repair large segmental bone defects.

Combination of Heel-strike like Mechanical Loading with Deproteinized Cancellous Bone Scaffold Implantation to Repair Segmental Bone Defects in Rabbits.

Under physiological conditions bone defects often occur at mechanical load bearing sites and bone substitutes used for regeneration should be similarly subjected to mechanical loading stress. In this study, we investigated whether a novel heel-strike like mechanical loading method can be used as a complementary therapy to promote bone regeneration following bone substitute grafting. To test this, three groups of rabbits with segmental bone defects in the tibia were implanted with bovine deproteinized cancellous bone scaffold (DCBS), with one group also receiving heel-strike like mechanical loading generated by a rap stress stimulator. From weeks 4-12 post-operation X-ray and micro-CT scanning showed that rabbits receiving combination therapy had significantly more callus at the bone defect. Moreover, bone defects in the combination group were completely replaced with new bone at week 12, while the DCBS implantation alone group healed only partially and rabbits receiving neither DCBS nor mechanical loading developed only small calluses throughout the observation period. Analysis of micro-CT scanning results demonstrated that new bone density in the combination group was significantly higher than the DCBS only group at weeks 4 and 12 (p<0.05). H&E staining results also indicated a significantly higher percentage of new bone in the bone defect area and a lower percentage of residual scaffold in the combination group compared to the DCBS only group (p<0.05). Thus, this heel-strike like mechanical loading method appears to accelerate bone regeneration following substitute implantation by restoring a local mechanical loading environment in segmental bone defects.

Effects of Pore Size on the Osteoconductivity and Mechanical Properties of Calcium Phosphate Cement in a Rabbit Model.

Calcium phosphate cement (CPC) porous scaffold is widely used as a suitable bone substitute to repair bone defect, but the optimal pore size is unclear yet. The current study aimed to evaluate the effect of different pore sizes on the processing of bone formation in repairing segmental bone defect of rabbits using CPC porous scaffolds. Three kinds of CPC porous scaffolds with 5 mm diameters and 12 mm length were prepared with the same porosity but different pore sizes (Group A: 200-300 µm, Group B: 300-450 µm, Group C: 450-600 µm, respectively). Twelve millimeter segmental bone defects were created in the middle of the radius bone and filled with different kinds of CPC cylindrical scaffolds. After 4, 12, and 24 weeks, alkaline phosphatase (ALP), histological assessment, and mechanical properties evaluation were performed in all three groups. After 4 weeks, ALP activity increased in all groups but was highest in Group A with smallest pore size. The new bone formation within the scaffolds was not obvious in all groups. After 12 weeks, the new bone formation within the scaffolds was obvious in each group and highest in Group A. At 24 weeks, no significant difference in new bone formation was observed among different groups. Besides the osteoconductive effect, Group A with smallest pore size also had the best mechanical properties in vivo at 12 weeks. We demonstrate that pore size has a significant effect on the osteoconductivity and mechanical properties of calcium phosphate cement porous scaffold in vivo. Small pore size favors the bone formation in the early stage and may be more suitable for repairing segmental bone defect in vivo.

Repair of segmental radial defects in dogs using tailor-made titanium mesh cages with plates combined with calcium phosphate granules and basic fibroblast growth factor-binding ion complex gel.

Repair of large segmental defects of long bones are a tremendous challenge that calls for a novel approach to supporting immediate weight bearing and bone regeneration. This study investigated the functional and biological characteristics of a combination of a tailor-made titanium mesh cage with a plate (tTMCP) with tetrapod-shaped alpha tricalcium phosphate granules (TB) and basic fibroblast growth factor (bFGF)-binding ion complex gel (f-IC gel) to repair 20-mm segmental radial defects in dogs. The defects were created surgically in 18 adult beagle dogs and treated by implantation of tTMCPs with TB with (TB-gel group) or without (TB group) f-IC gel. Each tTMCP fitted the defect well, and all dogs could bear weight on the affected limb immediately after surgery. Dogs were euthanized 4, 8 and 24 weeks after implantation. Histomorphometry showed greater infiltration of new vessels and higher bone union rate in the TB-gel group than in the TB group. The lamellar bone volume and mineral apposition rate did not differ significantly between the groups, indicating that neovascularization may be the primary effect of f-IC gel on bone regeneration. This combination method which is tTMCP combined with TB and f-IC gel, would be useful for the treatment of segmental long bone defects.

Papineau technique combined with vacuum-assisted closure for open tibial fractures: clinical outcomes at five years.

PURPOSE: Treatment of open tibial fractures with soft tissue and segmental bone defects is difficult. This study reports our results for treating these injuries with a combination of Papineau open bone grafting and vacuum-assisted wound closure (VAC). METHODS: The records of 19 patients with open tibial fractures with soft tissue and segmental bone defects treated with bone grafting and VAC from 2004 to 2010 were retrospectively reviewed. Outcomes included: time to complete granulation tissue coverage, wound healing, and bone union; length of hospitalization; frequency of debridement; number of deep tissue infections. RESULTS: Initial surgery was performed within 48 hours of injury. Ten fractures were Orthopaedic Trauma Association classification 41-A3, one was 41-C3, seven were 43-A3, and one was 43-C3. No surgical complications occurred, and the mean length of hospitalization was 11.0 ± 3.0 weeks (range, 7-18 weeks). The mean follow-up time was 59.35 ± 8.76 months. The mean time for complete wound healing was 7.76 ± 1.52 weeks (range, 6-11 weeks). Bone union was achieved in all patients at a mean of 33.88 ± 8.37 weeks (range, 23-53 weeks). Only one patient developed a deep tissue infection, which was treated with antibiotics and debridements, and complete bone union wound healing was achieved. Based on Paley grade, five outcomes were excellent, eight were good, and four were fair. CONCLUSIONS: The combination of VAC and open bone grafting results in good outcome for patients with open tibial fractures and severe bone and soft-tissue defects.

Autologous bone graft in the treatment of post-traumatic bone defects: a systematic review and meta-analysis.

BACKGROUND: This meta-analysis aimed to determine the bone union rate of bone defects treated with the different autologous bone graft techniques. METHODS: The PubMed and the Cochrane Library databases were searched using the terms: 'fracture' AND ('bone loss' OR 'defect' OR 'defects') AND 'bone graft', restricted to English language, to human species, and to a publication period from January 1999 to November 2014. Data were extracted by one of the reviewers and then checked by the second. A quality of evidence score and a methodology score were used. Heterogeneity was assessed. A random effects model approach was used to combine estimates. RESULTS: Out of 376 selected studies only 34 met the inclusion criteria. The summary pooled union rate was 91 % (95 % CI: 87-95 %) while union rate after additional procedures raised to 98 % (95 % CI 96-99 %). No association between union rate and bone defect size was found. (Univariable regression model: vascularized: P = 0.677; non-vascularized: 0.202. Multivariable regression model: vascularized: P = 0.381; non-vascularized: P = 0.226). Vascularized graft was associated with a lower risk of infection after surgery when compared to non-vascularized graft (95 % CI 0.03 to 0.23, p < 0.001). CONCLUSION: The results of this meta-analysis demonstrate the effectiveness of autologous graft for bone defects. Furthermore, from the available clinical evidence bone defect size does not seem to have an impact on bone union when treated with autologous bone graft techniques.

Masquelet technique for treatment of segmental bone loss in the upper extremity.

A relatively simple technique to address large segmental bone defects in the upper extremity is described, along with a case example.

Controlling the pore size of carbonate apatite honeycomb scaffolds enhances orientation and strength of regenerated bone.

To restore functions of long bones and avoid reconstruction failure, segmental defects should be quickly repaired using abundant amounts of regenerated bone with high mechanical strength and orientation along the bone axis. Although both bone volume and bone matrix orientation are important for faster restoration of long bones with segmental defects, researchers have primarily focused on the former. Artificial bone scaffolds with uniaxial channels, (e.g., honeycomb (HC) scaffolds), are considered adequate for regenerating bone oriented along the bone axis. The channel size may affect the orientation, amount, and strength of the regenerated bone. In this study, we investigated the effects of channel size in carbonate apatite HC scaffolds on the orientation of bones regenerated in segmental bone defects and determined the adequate channel size. Carbonate apatite HC scaffolds, with different channel sizes (350, 550, 730, and 890 µm in length on the side of the square aperture), were fabricated by extrusion molding of a mixture of calcium carbonate and organic binder, debinding, and subsequent phosphatization to convert the composition from calcium carbonate to carbonate apatite. No significant difference in the amounts of regenerated bones was observed for different channel sizes. However, bone along the bone axis was formed in the channels ≤550 µm in size but not in channels ≥730 µm. The HC scaffolds with a channel size of 350 µm regenerated bone with higher bending strength than those with a channel size of 890 µm. However, bone regenerated with the HC scaffolds having channel sizes of 350, 550, and 730 µm showed equal bending strength. Thus, the adequate channel size for fast regeneration of high-strength bone, oriented to the bone axis, is ≤730 µm. To the best of our knowledge, this is the first study to report the effect of channel size on bone orientation and strength. The findings of this study are relevant to the fast repair of segmental bone defects.

Strontium-loaded 3D intramedullary nail titanium implant for critical-sized femoral defect in rabbits.

The treatment of critical-sized bone defects has long been a major problem for surgeons. In this study, an intramedullary nail shaped three-dimensional (3D)-printed porous titanium implant that is capable of releasing strontium ions was developed through a simple and cost-effective surface modification technique. The feasibility of this implant as a stand-alone solution was evaluated using a rabbit's segmental diaphyseal as a defect model. The strontium-loaded implant exhibited a favorable environment for cell adhesion, and mechanical properties that were commensurate with those of a rabbit's cortical bone. Radiographic, biomechanical, and histological analyses revealed a significantly higher amount of bone ingrowth and superior bone-bonding strength in the strontium-loaded implant when compared to an untreated porous titanium implant. Furthermore, one-year histological observations revealed that the strontium-loaded implant preserved the native-like diaphyseal bone structure without failure. These findings suggest that strontium-releasing 3D-printed titanium implants have the clinical potential to induce the early and efficient repair of critical-sized, load-bearing bone defects.

Computer-aided design and 3D printing for a stable construction of segmental bone defect model in Beagles: a short term observation.

OBJECTIVE: Segmental bone defect animal studies require stable fixation which is a continuous experimental challenge. Large animal models are comparable to the human bone, but with obvious drawbacks of housing and costs. Our study aims to utilize CAD and 3D printing in the construction of a stable and reproducible segmental bone defect animal mode. METHODS: CAD-aided 3D printed surgical instruments were incorporated into the construction of the animal model through preoperative surgical emulation. 20 3D printed femurs were divided into either experimental group using 3D surgical instruments or control group. In Vitro surgical time and accuracy of fixation were analysed and compared between the two groups. A mature surgical plan using the surgical instruments was then utilized in the construction of 3 segmental bone defect Beagle models in vivo. The Beagles were postoperatively assessed through limb function and imaging at 1, 2 and 3 months postoperatively. RESULTS: In vitro experiments showed a significant reduction in surgical time from 40.6 ± 14.1 (23-68 min) to 26 ± 4.6 (19-36 min) (n = 10, p < 0.05) and the accuracy of intramedullary fixation placement increased from 71.6 ± 23.6 (33.3-100) % to 98.3 ± 5.37 (83-100) %, (n = 30, p < 0.05) with the use of CAD and 3D printed instruments. All Beagles were load-bearing within 1 week, and postoperative radiographs showed no evidence of implant failure. CONCLUSION: Incorporation of CAD and 3D printing significantly increases stability, while reducing the surgical time in the construction of the animal model, significantly affecting the success of the segmental bone defect model in Beagles.

Induced Membrane Technique for the Management of Segmental Femoral Defects: A Systematic Review and Meta-Analysis of Individual Participant Data.

Several modifications of the induced membrane technique (IMT) have been reported, but there is no consensus regarding their results and prognosis. Moreover, most studies have focused on tibial defects; no meta-analysis of the treatment of femoral defects using the IMT has been reported. This systematic review and meta-analysis aimed to identify the potential risk factors of post-procedural complications following the treatment of segmental femoral defects using the IMT. A comprehensive search was performed on the Cochrane Library, EBSCO, EMBASE, Ovid, PubMed, Scopus, and Web of Science databases, using the keywords "femur," "Masquelet technique," and "induced membrane technique." Original articles composed in English, having accessible individual patient data, and reporting more than two cases of bony defect or nonunion of femur or more than five cases of any body part were included. Post-procedural bone graft infections, final union status, and union time after second-stage operation were analyzed. Fourteen reports, including 90 patients, were used in this study. External fixation in second-stage surgery had an odds ratio of 9.267 for post-procedural bone graft infection (p = 0.047). The odds ratio of post-procedural bone graft infection and age >65 years for final non-union status was 51.05 (p = 0.003) and 9.18 (p = 0.042). Shorter union time was related to impregnated antibiotics in the spacer (p = 0.005), transplanting all-autologous grafts (p = 0.042), and the application of intramedullary nails as the second-stage fixation method (p = 0.050). The IMT appears to be reasonable and reproducible for femoral segmental bone defects. Several preoperative and surgical factors may affect post-procedural complications and union time.

Evaluation of a Bioabsorbable Scaffold and Interlocked Nail System for Segmental Bone Defect.

In the current study, we designed and manufactured a scaffold and fixation system for the reconstruction of long-bone segmental defects in a rabbit tibia model. We used biocompatible and biodegradable materials, polycaprolactone (PCL) and PCL soaked with sodium alginate (PCL-Alg) to manufacture the scaffold, interlocking nail and screws using a phase separation casing method. Degradation and mechanical tests on the PCL and PCL-Alg scaffolds indicated that both were suitable for faster degradation and early weight-bearing capacity. PCL scaffold surface porosity facilitated the infiltration of alginate hydrogel through the scaffold. Cell viability results showed that the number of cells increased on Day 7 and decreased marginally by Day 14. For accurate placement of the scaffold and fixation system, a surgical jig was designed and 3D-printed using biocompatible resin in a stereolithography (SLA) 3D printer, then cured with UV light for increased strength. Our cadaver tests using New Zealand White rabbit confirmed our novel jigs' potential for accurate placement of the bone scaffold, intramedullary nail and the alignment of the fixation screws in future reconstructive surgeries on rabbit long-bone segmental defects. Additionally, the cadaver tests confirmed that our designed nails and screws were strong enough to carry the surgical insertion force. Therefore, our designed prototype has the potential for further clinical translational study using the rabbit tibia model.

Definitive fixation in the first stage of the induced membrane technique for septic segmental bone defects. Why not?

Background: Infected segmental bone defects (I-SBD) are challenging and complex to manage. This study aimed to show the outcomes achieved in I-SBD of the femur and tibia, treated with the induced membrane technique performing a definitive bone stabilization in the first stage. Methods: We retrospectively reviewed 30 patients with infected non-articular segmental bone defects of the femur (n = 11) and tibia (n = 19), operated consecutively between January 2015 and May 2021. The need for fixation exchange, bone defect length, allo/autograft ratio used, bone healing, reoperation (discriminating between mechanical and infection-related causes), and failure rates (graft resorption or nonunion) were recorded. Results: Fixation in the first stage was performed with 28 (93.33%) intramedullary nails, ten coated with antibiotic cement, and 2 (6.67%) locked plates. None were removed during the second stage of the technique. The mean length of the bone defects was 5cm (range 3.5-12). The most commonly used allo-/autograft ratio was 50-50. The bone healing rate was 93.33% (n = 28), with a median follow-up of 7 months (range 3-12). The reoperation rate due to mechanical instability was 3.33% (n = 1) and for recurrence of infection was 10.0% (n = 3). The overall failure rate was 6.67% (n = 2). The median follow-up was 42 months (range 12-85). Conclusion: Masquelet technique appears feasible and effective in treating infected segmental bone defects of the femur and tibia. Definitive fixation at the first stage showed a success rate of 93.33%, with a re-operation rate of 10.0% related to infection.