Characterization of the Masquelet Induced Membrane Technique in a Murine Segmental Bone Defect Model / Caracterização da membrana induzida pela técnica de Masquelet em modelo murino de defeito ósseo segmentar

Abstract Objective To reproduce in an animal model the surgical technique of Masquelet used in the treatment of critical bone defects and to analyze the characteristics of the membrane formed around the bone cement. Methods A 10mm critical defect was created in the femoral shaft of 21 Sprague-Dawley rats. After resection of the central portion of the diaphysis, the defect was stabilized with a Kirschner wire introduced through the medullary canal and with the interposition of a bone cement spacer. After 2, 4, and 6 weeks of the surgical procedure, the animals were euthanized and evaluated on radiographs of the posterior limb regarding the size of the defect, alignment and stability of the osteosynthesis. The membranes formed around the spacer were subjected to histological analysis to assess thickness, connective tissue maturation and vascular density. Results Over time, the membranes initially made up of loose connective tissue were replaced by membranes represented by dense connective tissue, rich in thick collagen fibers. At six weeks, membrane thickness was greater (565 ± 208μm) than at four (186.9 ± 70.21μm, p = 0.0002) and two weeks (252.2 ± 55.1μm, p = 0.001). All membranes from the initial time showed foci of osteogenic differentiation that progressively reduced over time. Conclusion In addition to the structural and protective function of the membrane, its intrinsic biological characteristics can actively contribute to bone regeneration. The biological activity attributed by the presence of foci of osteogenesis confers to the membrane the potential of osteoinduction that favors the local conditions for the integration of the bone graft.

Resumo Objetivo Reproduzir em modelo animal a técnica cirúrgica de Masquelet utilizada no tratamento de defeitos ósseos críticos e analisar as características da membrana formada em torno do cimento ósseo. Métodos Um defeito crítico de 10mm foi realizado na diáfise femoral de 21 ratos Sprague-Dawley. Após a ressecção da porção central da diáfise o defeito foi estabilizado com fio de Kirschner introduzido pelo canal medular e com a interposição de espaçador de cimento ósseo. Após 2, 4, e 6 semanas do procedimento cirúrgico os animais foram eutanasiados e avaliados em radiografias do membro posterior quanto ao tamanho do defeito, o alinhamento e a estabilidade da osteossíntese. As membranas formadas em torno do espaçador foram submetidas a análise histológica para avaliação da espessura, da maturação do tecido conjuntivo e da densidade vascular. Resultados Ao longo do tempo as membranas inicialmente constituídas por tecido conjuntivo frouxo foram substituídas por membranas representadas por tecido conjuntivo denso, rico em fibras colágenas espessas. Com seis semanas a espessura das membranas foi maior (565 ± 208μm) do que com quatro (186,9 ± 70,21μm, p = 0,0002) e duas semanas (252,2 ± 55,1μm, p = 0,001). Todas as membranas do tempo inicial apresentaram focos de diferenciação osteogênica que reduziram progressivamente ao longo do tempo. Conclusão Além da função estrutural e protetora da membrana, suas características biológicas intrínsecas podem contribuir ativamente para a regeneração óssea. A atividade biológica atribuída pela presença de focos de osteogênese confere à membrana potencial de osteoindução que favorece as condições locais para a integração do enxerto ósseo.

Masquelet induced membrane technique combined with an external locking plate for treatment of infectious bone defects of the tibia / 中华创伤骨科杂志

Objective:To investigate the efficacy of Masquelet induced membrane technique combined with an external locking plate in the treatment of infectious bone defects of the tibia.Methods:A retrospective study was conducted to analyze the data of 32 patients with infectious bone defects of the tibia who had been treated by Masquelet induced membrane technique combined with an external locking plate at Department of Orthopaedic Surgery, The Fourth Hospital of Wuhan from January 2011 to January 2021. There were 22 males and 10 females, with an age of (43.2±13.1) years. The length of bone defects was (5.1±1.3) cm. By the Cierny-Mader classification, there were 12 cases of type Ⅲ and 20 cases of type Ⅳ. The defects were located at the proximal tibia in 11 cases, at the middle tibia in 12, and at the distal tibia in 9. At the last follow-up, the lower limb function was evaluated by the Paley scale, and the quality of life by the 36-Item Short Form Health Survey (SF-36).Results:All the 32 patients were followed up for (21.2±5.7) months. Normal healing was achieved in 30 cases but delayed healing occurred in 2 cases. The external plate and screws were removed at (23.1±4.6) weeks after operation. There was no infection in the original surgical incision or no injury to the nerve, blood vessel or tendon after operation, but nail tract infection occurred more or less in 3 cases. According to the Paley scale at the last follow-up, the lower limb function was evaluated as excellent in 22 cases, as good in 8, and as fair in 2, giving an excellent and good rate of 93.75% (30/32). The SF-36 quality of life score was (88.9±3.8) points.Conclusion:In the treatment of infectious bone defects of the tibia, Masquelet induced membrane technique combined with an external locking plate can achieve satisfactory clinical outcomes due to its effective control of infection, reduction in delayed healing, good stability and good patient tolerance.

Treatment of Post - traumatic Bone Defects with infection in L ong B ones

Background: Open fractures are a challenging condition to treat because they are frequently compounded by infection and nonunion. Traditional bone defect care strategies are mostly focused on fracture union rather than infection prevention. The goal of this study is t o use the Masquelet approach to examine the outcome of a post - traumatic defect with infection in long bones. This method is a two - step process. Stage I surgery includes debridement and the placement of an antibacterial spacer in the bone defect. Stage II s urgery involved removing the spacer while preserving the induced membrane that had grown on the spacer's surface and filling the bone - gap with morselized iliac crest bone - graft within the membrane sleeve. Methods: There were 22 patients in this study (18 m ales and 4 females), all of them had infected long bone fractures with a bone defect. The average length of the bone defect was 3.5 centimetres. The duration of follow - up varied from 6 to 15 months. Results: After an average of 11.5 weeks following the fir st step of surgery, radiological union was achieved. After stage 1, no patient had any remaining infection. After radiological union, all of the patients were able to mobilise with full weight bearing and a satisfactory range of motion in the adjoining joi nts. Conclusion: With favourable outcomes, this treatment can be used on infected fractures with bone loss on a regular basis. Antibiotic cement spacers, used in conjunction with complete debridement, minimise the risk of infection. The graft is revascular ized through induced biomembrane. In most circumstances, union may be predicted; nonetheless, the length of time it takes to reach an agreement is a constraint. The technique is low - cost and does not necessitate any additional training or equipment. Despit e the fact that it is a two - stage procedure, it does not necessitate several surgeries as in traditional approaches.

Modified Masquelet technique with pedicled myocutaneous flap in repair of diabetic soft tissue and tibial bone defects / 中华显微外科杂志

Objective:To investigate the effect and indications of pedicled myocutaneous flap and modified Masquelet technique in the repair of diabetic soft tissue and tibial bone defects.Methods:From January, 2017 to October, 2019, data of surgical treatment of 20 patients with diabetic soft tissue and tibial bone defects were retrospectively studied. The detects were repaired by the pedicled myocutaneous flap combined with modified Masquelet technique. There were 13 males and 7 females aged 40 to 65(average 51) years old. Preoperative ultrasound and CTA had confirmed that there was no occlusion in anterior and posterior tibial arteries. After debridement, the bone defect was 4-9 cm in length and the soft tissue defect was 3 cm×6 cm to 7 cm×10 cm. The initial antibiotic loaded bone cement filling of the bone and soft tissue defects was carried out. Then at 7-10 days later, had the bone cement placed earlier removed the remaining spaces of bone defect were again filled by antibiotic loaded bone cement. Meanwhile, the pedicled myocutaneous flap was transferred to repair the wound. The second stage of Masquelet technique was performed later, with an interval of 8-12(mean 9) weeks. The healing of wound and bone defect, and the complications were recorded. At 12 months after the surgery, the healing and appearance of the flap were evaluated by the standard proposed by Zhang Hao, and the functional recovery of the adjacent joint was evaluated by Johner-Wruhs standard. The treatment was considered successful when the symptoms were disappeared and no recurrence occurred.Results:All patients entered 13 to 28 months of follow-up, 20 months in average. The healing time for bone defect was 6-11 (average 9.0) months. All myocutaneous flaps survived with 18 flaps healed in the stage one and 2 delayed healing. Nine flaps appeared almost normal and 11 shown bloating. Seventeen flaps were found with partial sensation and 3 without sensation at all. The temperature of 7 flaps was found normal and 13 were slightly lower. Fourteen donor site scars were mild and 6 were obvious. The overall curative effect was satisfactory. Two patients had recurred infection. The rates of excellent and good functional recovery, infection control and success of treatment were at 90%(18/20) for each.Conclusion:Pedicled myocutaneous flap combined with modified Masquelet technique can repair diabetic soft tissue and tibial bone defects. It has a good therapeutic effect for short and medium terms.

Aneurysmal Bone Cyst of the Lateral Malleolus Treated with Intralesional Curettage and Masquelet Technique: A Case Report

@#An aneurysmal bone cyst is a locally destructive lesion considered to be a pseudotumor arising from the bone. Although this benign-like lesion is generally considered rare, several approaches for treatment have been presented. We report a case involving a 15-year-old female diagnosed with aneurysmal bone cyst of the lateral malleolus. Applying the Masquelet technique enabled the treatment of the lesion without causing instability to the ankle joint and the prevention of recurrence through the application of polymethylmethacrylate. To our knowledge this is the first documented case in our region and possibly in the Philippines.

Técnica de Masquelet para defecto óseo en quinto metatarsiano. Reporte de caso clínico / Masquelet technique for fifth metatarsal bone defect. Case report

Introducción la técnica de masquelet se utiliza en el tratamiento de los defectos óseos de los huesos largos con éxito. En el pie se ha descrito para el tratamiento de perdidas oseas en el 1er metatarsiano y medio pie. El objetivo del reporte de caso es describir la experiencia con la técnica en paciente con defecto óseo del cuarto y quinto metatarsianos asociado a defecto cutáneo transfixiante Reporte de caso En un paciente de 42 años que presentó herida por proyectil de arma de fuego sobre columna lateral de pie derecho con posterior defecto de cobertura transfixiante y defecto óseo por fractura conminuta de cuarto y quinto metatarsianos. Se realizó tratamiento quirúrgico en 3 tiempos, el primero estabilización y lavado quirúrgico, 2do tiempo Cobertura con colgajo sural de flujo reverso, fijación con placa y espaciador de cemento. Para un tercer tiempo se realiza retiro de cemento y colocación de injerto óseo cortico esponjoso autólogo. Se realiza seguimiento clínico y radiológico a 18 meses. Resultados el paciente no presentó complicaciones, presenta área de anestesia en territorio del sural, viabilidad completa del colgajo, no presentó infecciones. Se evidencia marcha normal sin metatarsalgia, en la evaluación radiológica presenta integración del injerto en el 90%, adecuado espacio sobre la artroplastia de interposición cuboideo metatarsiana, con un EVA de 1/10 y una AOFAS midfoot score de 85. Discusión Existen 7 reportes en la literatura acerca de la técnica de masquelet en el pie, con resultados favorables en su mayoría con restitución funcional en casos complejos y ningún reporte sobre la columna lateral. En nuestro caso la técnica demuestra ser una alternativa viable lográndose la restitución funcional y estructural del pie.

Background The Masquelet technique is used in the treatment of bone defects in long bones with high success rete reports. It has been described for the treatment of bone loss in the 1st metatarsal and midfoot. The aim of the report is to describe the experience with the technique in a patient with a bone defect of the fourth and fifth metatarsals associated with a transfixing skin defect. Case report In a 42-year-old patient who presented a gunshot wound to the lateral column of the right foot with subsequent transfixing coverage defect and bone defect due to comminuted fracture of the fourth and fifth metatarsals. Surgical treatment was performed in 3 stages, the first stabilization and surgical lavage, 2nd stage coverage with a reverse flow sural flap, fixation with a plate and a cement spacer. For a third stage, the bone cement was removed and an autologous cortico-cancellous bone graft was placed. Clinical and radiological follow-up was carried out for 18 months. Results The patient did not present complications including infection, presented anesthesia area in the sural nerve territory, complete viability of the flaps. Normal gait without metatarsalgia was evidenced and in the radiological evaluation it presents graft integration of 90% at described follow up term. Adequate space over the metatarsal cuboid interposition arthroplasty was observed, with a VAS of 1/10 and an AOFAS mid foot score OF 85. Discussion There are 7 reports in the literature about the Masquelet technique in the foot, with favorable results, mostly with functional restoration in complex cases in the medial column and no reports on the lateral column. In our case, the technique proves to be a viable alternative, achieving functional and structural restitution of the foot.

Comparison of in vivo versus in vitro fabrication of bone cement spacers in Masquelet technique for bone defects / 中华创伤骨科杂志

Objective:To compare in vivo versus in vitro fabrication of bone cement spacers in the treatment of bone defects by Masquelet technique. Methods:The data of 128 patients were analyzed retrospectively who had been treated for bone defects by Masquelet technique at Department of Orthopedics, Wuxi No. 9 People’s Hospital from January to August 2019. They were 74 males and 54 females, aged from 13 to 77 years. Their bone defects were traumatic in 54 cases and infectious in 74 cases. In 76 of them ( in vivo group), after a bone cement spacer was implanted into a bone defect during its dough phase, it was fabricated in vivo to form a cylindrical structure which was as large as or slightly larger than the defect size. In the other 52 cases ( in vitro group), before a bone cement spacer was implanted into a bone defect, it was fabricated in vivo during its dough phase into a cylindrical or block or bead chain or spherical form which was naturally solidificated at room temperature. The 2 groups were compared in terms of spacer filling time, bone healing time, delayed healing rate, infection control rate, spacer removal time, incidence of induced membrane or broken end bone lesion, as well as upper limb function evaluated by the Disability of the Arm, Shoulder and Hand Questionnaire (DASH) and the Paley lower limb grading at the last follow-up. Results:The 2 groups were comparable because there was no significant difference between them in gender, age, ratio of infected to non-infected cases, combined injuries, comorbidities or number of operations ( P>0.05). All the patients were followed up for 12 to 50 months (mean, 18.6 months). There were no significant differences between the 2 groups in spacer filling time, bone healing time, delayed healing rate, infection control rate or functional recovery for upper or lower limbs or for large or small bone defects (all P>0.05). In the in vivo group, for upper and lower limbs and for large and small bone defects respectively, the spacer removal time [(3.6±1.0) min, (4.1±1.1) min, (4.0±1.1) min and (3.9±1.0) min] and the incidence of induced membrane or broken end bone lesion [48.1%(13/27), 73.5%(36/49), 82.6%(39/46) and 66.7%(20/30)] were significantly longer or higher than those in the in vitro group [all (0.4±0.2) min; 3.2%(1/31), 9.5%(2/21), 0 (0/21) and 0 (0/31)] (all P<0.05). Conclusions:In the treatment of bone defects by Masquelet technique, in vivo and in vitro fabrication of bone cement spacers may lead to similar therapeutic effects. In vivo fabrication may be more suitable for lower limb, large or unstable bone defects but the spacer is not easy to remove and the induced membrane or bone ends are likely to get injured while in vitro fabrication may be more suitable for partial, small or upper limb defects because it may produce a variously shaped spacer.

Masquelet technique combined with flap transplantation for infectious bone and soft tissue defects of lower leg / 中国修复重建外科杂志

Objective: To investigate the effectiveness of Masquelet technique combined with flap transplantation in treatment of infectious bone and soft tissue defects of the lower leg. Methods: Between January 2013 and January 2017, 35 cases of infectious bone and soft tissue defects of lower leg were treated with Masquelet technique combined with flap transplantation. There were 21 males and 14 females, with an average of 31.5 years (mean, 25-55 years). All patients were tibial fractures caused by trauma and the infections occurred after debridement or internal fixation. The time from injury to admission was 1 to 6 months, with an average of 3.2 months. Defect located at the proximal leg in 11 cases, the middle leg in 11 cases, and the distal leg in 13 cases. The length of tibia defect after debridement ranged from 5.6 to 11.2 cm, with an average of 7.1 cm. The size of soft tissue defect ranged from 14.2 cm×6.9 cm to 17.3 cm×8.7 cm. Bacterial culture of purulent secretion of wound was positive in 18 cases. After debridement, the bone cement was used to fill the bone defect and the flap transplantation was used to repair the wound. The bone cement was taken out at 8 to 12 weeks after the one-stage operation, and the bone defect was repaired with autogenous iliac bone or combined with artificial bone. Results: Three cases had necrosis at the distal edge of the flap after one-stage operation, and survived after dressing change. The other flaps survived successfully, and the wounds healed by first intention. All incisions healed by first intention after two-stage operation. All patients were followed up 24-32 months, with an average of 27 months. The color of the flap was similar to that of the surrounding normal tissue, and its texture was good. X-ray reexamination showed that all bone defects healed after 6-8 months, with an average of 6.7 months. At 9 months after two-stage operation, according to the revised Edwards tibial fracture evaluation standard, 19 cases were excellent, 14 cases were good, and 2 cases were poor, the excellent and good rate was 94.3%. The American Orthopedic Ankle Association (AOFAS) score was 60-98, with an average of 81.3. And 21 cases were excellent, 11 were good, and 3 were fair, with an excellent and good rate of 91.4%. Conclusion: Masquelet technique combined with flap transplantation is an effective treatment for infectious bone and soft tissue defects of lower leg.

Effect of glycoside of short-horned epimedium Herb on the expressions of transforming growth factor β 1 and basic fibroblast growth factor induced membrane by Masquelet technology / 中国修复重建外科杂志

Objective: To observe the expressions of transforming growth factor β 1 (TGF-β 1) and basic fibroblast growth factor (bFGF) induced membrane by Masquelet technique in rats treated with glycoside of short-horned epimedium Herb, and to explore the effect of glycoside of short-horned epimedium Herb on Masquelet induced membrane. Methods: Sixty 3-month-old male Wistar rats were randomly divided into 3 groups with 20 rats in each group; a tibial bone defect (6 mm in length) model was established. The blank group (group A) was not treated; the control group (group B) and the experimental group (group C) were filled with vancomycin antibiotic bone cement in the drawing stage, and the bone cement was completely solidified. Group C was given perfused flavonoids glycoside of short-horned epimedium Herb (10 μmol/L) by gavage once a day (0.3 mL) from 1 day after operation, and groups A and B were given the same amount of normal saline by gavage. After operation, the recovery and wound healing of experimental animals were observed; at 4 weeks after operation, X-ray film was taken to observe the recovery of bone defect of proximal tibia; at 6 weeks after operation, the bone defect was observed, and the morphological changes and vascularization degree of granulation tissue and induction membrane tissue were observed; the expressions of TGF-β 1 and bFGF were observed by immunohistochemistry staining and ELISA detection. Results: The bone defect models of the 3 groups were established successfully, and there was no abnormality after operation. The incisions healed by first intention after operation. At 4 weeks after operation, X-ray films of proximal tibial defect showed that there was obvious space in group A, while bone cement was filled and Kirschner wire fixation was good in groups B and C. At 6 weeks after operation, the gross observation showed that the granulation tissue was filled in the defect area in group A; transparent membrane was formed in groups B and C, and microvessels were seen in some areas, and the microvessels in group C were significantly more than those in group B. Immunohistochemical staining showed that the expressions of TGF-β 1 and bFGF were negative in group A, but they were expressed in groups B and C, and the expressions of TGF-β 1 and bFGF in group B were significantly less than those in group C. ELISA detection showed that the expressions of TGF-β 1 and bFGF in group C were significantly higher than those in groups A and B ( P0.05). Conclusion: Glycoside of short-horned epimedium Herb can significantly increase the expressions of TGF-β 1 and bFGF, accelerate the process of osteogenesis, and contribute to bone shaping and reconstruction.

Bone healing effects of early-stage versus late-stage bone grafting within induced membrane / 中国组织工程研究

BACKGROUND: It remains unclear regarding the difference in bone healing effects after early-stage versus late-stage bone grafting within induced membrane. OBJECTIVE: To investigate the difference in bone healing effects of bone grafting within induced membrane in the repair of bone defects and the major factors that affect bone healing. METHODS: Sixty-three patients with tibial bone defect who received treatment with induced membrane technique during January 2007 to August 2017 in Wuxi People’s Hospital and Wuxi Orthopedics Hospital, China. These patients consisted of 38 males and 25 females and were aged 16-69 years. According to the time of bone grafting within induced membrane after bone cement filling, these patients were divided into an early stage group (n=25, bone grafting in the induced membrane 6-8 weeks after filling bone cement) and a late stage group (n=38, bone grafting in the induced membrane 10-12 weeks after filling bone cement). The healing of bone defect and functional recovery of affected limbs were evaluated. The causes of delayed healing and nonunion were analyzed. This study was approved by the Medical Ethics Committee of Wuxi People’s Hospital and Wuxi Orthopedics Hospital, China (approval No. LW2019001). RESULTS AND CONCLUSION: Bone graft was successfully completed in 63 patients. The induced membrane formed in the early stage group was thin and there were relatively more capillaries, while the induced membrane formed in the late stage group was usually thick and there were relatively few capillaries. All 63 patients were followed up for 16-50 months. In the early stage group, the wound or incision healed at first intention in 22 patients and delayed healing was observed in 3 patients. In the late stage group, the wound or incision healed at first intention in 34 patients, delayed healing was observed in 2 patients, and healing by the second intention was observed in 2 patients. In the early stage group, there was 1 patient developing delayed healing, no nonunion was observed, the clinical healing time was averaged 6.64 (range 5.0-12.0 months) months. In the late stage group, delayed healing occurred in 2 patients and nonunion was observed in 1 patient. The clinical healing time was averaged 7.42 (range 5.0-16.0 months) months. There were no significant differences in the healing time and nonunion between the early stage and late stage groups (P > 0.05). In the early stage group, excellent functional recovery of affected limb was observed in 13 patients, good recovery in 11 patients, and fair recovery in 1 patient, and it was 17, 18 and 3 patients respectively in the late stage group. There was no significant difference in functional recovery of affected limbs between early stage and late stage groups (P > 0.05). These results showed that bone grafting within the induced membrane at different time has slight, but not significant effect on healing of bone defect. Other factors, such as the size and the integrity of induced membrane, the quality and quantity of bone graft material, and the stability of bone stumps had more significant effects on the healing of bone defects, in particular on the healing rate.

Possibility of treating large bone defect and reducing the amount of autogenous bone using masquelet technique / 中国组织工程研究

BACKGROUND: Masquelet technique is one of the effective methods to repair large bone defects. This technique requires the use of more autologous bone in the second stage of surgical treatment. However, the source of autologous bone is limited and the complications in the donor area are inevitable. How to reduce the use of autologous bone is an urgent problem to be solved. OBJECTIVE: By combining with the development status of induced membrane technology at home and abroad, this review introduced some effective methods to reduce the amount of autologous bone in induced membrane technology, including filling bone graft replacement materials and some special surgical methods. METHODS: The first author used a computer to retrieve the literature published in PubMed, CNKI and Wanfang databases from January 1996 to September 2019. The search terms were “Masquelet technique; induced membrane; bone transport technique; autologous bone; bone defect; bone graft; 3D printing; tissue engineering”. RESULTS AND CONCLUSION: Since the emergence of the Masquelet technique, the technique has been constantly improved and innovated by scholars. However, there is no international consensus on how to reduce the use of autologous bone in the second stage of Masquelet technique. At present, each of improvement methods has its own advantages and disadvantages, and clinicians need to choose according to objective conditions. The method proposed by Jong-Keon Oh, using gelfoam as the bone grafting center and the peripheral ring for bone grafting, is simple and practical. Tissue engineering technology has potential for development. With the further study of seed cells and scaffold materials, it will gradually replace the existing treatment schemes. According to the existing research, the research direction of Masquelet technique in the future can be roughly summarized into four directions: The improvement of membrane technology, the improvement of surgical methods, the application of combined materials, and the application of 3D printing and tissue engineering technology. These directions need further exploration and development by scholars.

Limb Reconstruction Using Masquelet Technique in the Treatment of Post-traumatic Compound Tibial Fractures with Bone Loss

Introduction: Traumatic segmental bone defects of leg are difficult problem to manage with significant long-term morbidity.Historically, due to difficulty in managing segmental bone defects, amputation was the preferred treatment. Later over the lasthalf-century, limb salvage was done using various techniques such as vascularized fibular grafts, acute limb shortening, externalfixator application, and filling the defect with autograft or allograft. More recently, Masquelet described the use of cement spacerapplication within this defect and staged bone grafting within the induced biomembrane formed around the spacer as a potentialtreatment strategy to manage these bone defects.Method: This study describes the clinical, radiological, and functional outcome in 20 patients with traumatic bone loss of up to5 cm managed using Masquelet technique.Results: The outcome was analyzed using Association for the study and application of methods of ilizarov (ASAMI) scorewhich showed excellent results in 10 patients, good in 5 patients, fair in 2 patients, and poor in 3 patients.Conclusion: We conclude that the induced membrane technique can be a valuable addition to the armamentarium of limbreconstruction procedures in patients with small bone defects with or without soft tissue injury.

Masquelet technique combined with artificial dermis for the treatment of bone and soft tissue defects in rabbits / 中国修复重建外科杂志

Objective: To investigate the effect of Masquelet technique combined with artificial dermis on repairing bone and soft tissue defects in rabbits, and to observe the microstructure and vascularization of induced membrane, so as to guide the clinical treatment of Gustilo-Anderson type Ⅲ open fracture with large bone defect and soft tissue defect. Methods: Eighty male rabbits, weighing 2.03-2.27 kg (mean, 2.11 kg), were selected. The bilateral thighs of 64 rabbits were randomly divided into experimental group and control group, the remaining 16 rabbits were sham operation group. Bone and soft tissue defect models of femur were made in all rabbits. In the experimental group, the first stage of Masquelet technique was used [polymethyl methacrylate bone cement was filled in bone defect area] combined with artificial dermis treatment; in the control group, the first stage of Masquelet technique was used only; in the sham operation group, the wound was sutured directly without any treatment. Four rabbits in sham operation group and 16 rabbits in the experimental group and control group were sacrificed at 2, 4, 6, and 8 weeks after operation, respectively. The induced membranes and conjunctive membranes were observed on both sides of the femur. The membrane structure was observed by HE staining, and the microvessel density (MVD) was counted by CD34 immunohistochemical staining. Results: Gross observation showed that the spongy layer of collagen in the artificial dermis of the experimental group disappeared completely at 4 weeks after operation, and the induced membrane structure of the experimental group and the control group was complete; the membrane structure of the control group was translucent, and the membrane structure of the experimental group was thicker, light red opaque, accompanied by small vessel proliferation. The membrane structure of the experimental group and the control group increased gradually from 6 to 8 weeks after operation. In the sham operation group, only scar tissue proliferation was observed over time. HE staining showed that a large number of muscle fibers and a small amount of collagen fibers proliferation with inflammatory cell infiltration could be seen in the experimental group and the control group at 2 weeks after operation; most of the sham operation group were muscle fibers with a small amount of interfibrous vessels. At 4 weeks after operation, collagen fibers increased and some blood vessels formed in the experimental group. The nuclei of collagen fibers in the control group were round-like, while those in the experimental group were flat-round. At 6 and 8 weeks after operation, the collagen fibers in the experimental group and the control group increased. The nuclei of the collagen fibers in the control group were still round-like. The nuclei of the collagen fibers in the experimental group were fusiformis and deeply stained compared with those in the control group. The proliferation of blood vessels was observed in both groups, and the number of proliferation vessels in the experimental group was increased compared with that in the control group. In the sham operation group, a large number of fibroblasts still appeared, but no significant proliferation of blood vessels with time was observed. CD34 immunohistochemical staining showed that MVD in each group increased gradually with the prolongation of time after operation. MVD in the sham operation group was significantly higher than that in the experimental group and the control group at 2 weeks after operation, and significantly smaller than that in the experimental group and the control group at 4, 6, and 8 weeks after operation ( P0.05). Conclusion: Masquelet technique combined with artificial dermis in the treatment of femoral bone defect and soft tissue defect in rabbits can significantly promote the vascularization of membrane structure at 4-6 weeks after operation. The combination of these two methods has guiding significance for the treatment of Gustilo-Anderson type Ⅲ open fracture with bone and soft tissue defects.

Study progress in treatment of extremity bone defects / 中华创伤骨科杂志

Treatment of extremity bone defects,especially large segmental ones,is a difficult problem encountered by orthopedic surgeons in the clinic.Despite a variety of treatment techniques available,lack of uniform protocols causes patients to suffer enormous physical and psychological pain during their medical treatment.Now that new materials and new techniques are constantly evolving and patients' requirements for functional and morphological recovery of the injured limb become more demanding,it has become a great challenge for orthopedic surgeons to provide an optimal individualized treatment protocol for each patient.This review intends to help surgeons with brief update information on the research progress in the treatment of extremity bone defects.

Effects of different spacers on induced membranes in Masquelet technique / 中华创伤骨科杂志

Bone defects,a challenge in orthopedics,are mostly caused by severe trauma,bone tumor and bone infection.Their chief treatments include bone graft,distraction osteogenesis and Masquelet technique.Compared with other treatments,Masquelet technique is simpler and causes fewer complications,especially for infectious defects.In the first stage of Masquelet technique,a bone defect is filled with bone cement.The spacer most commonly used is polymethylmethacrylate(PMMA).PMMA can form induced membrane rich in blood vessels and bioactive components promoting osteogenesis,but it is not biodegradable,lacks bone conductibility,has an obvious thermal effect during operation,and is hard to remove in the second phase of Masquelet technique.Calcium sulfate and calcium phosphate bone cement are biodegradable materials which overcome the defects of PMMA due to their biological absorbability,bone conduction and bone inducement.It is possible for them to replace PMMA in Masquelet technique,but their poor mechanical strength limits their application.There is clinical evidence showing that calcium sulfate bone cement can form obvious induced membrane.As calcium silicate cement can also form a layer of fibrous tissue around the shell,it may be applied in orthopaedic surgery after improvement as a potential filling agent.A structure like induced membrane can form around a silicone prosthesis,and it functions similarly as induced membrane around PMMA and is more resistant to a radiation environment.Silicone has obvious advantages over PMMA after resection of bone tumor.Spacers used in the first stage of Masquelet technique have important effects on formation process and quality of induced membranes.By comparing membranes induced by different types of spacer,we can know more about the effects of spacers on induced membranes in the first stage of Masquelet technique and thus discover the most suitable spacers good for fracture healing and membrane formation.

Application of three-stage Masquelet technique for infective bone defects of foot and ankle / 中华创伤杂志

Objective To investigate the clinical efficacy of three-stage Masquelet technique in the treatment of infective bone defects of foot and ankle.Methods A retrospective case series study was conducted on the clinical data of 19 patients with infective bone defects of foot and ankle admitted to Zhongnan Hospital of Wuhan University from December 2014 to October 2017.There were 15 males and four females,aged 18-68 years [(39.6 ± 12.3)years].Among the patients,16 patients were infected with bacteria and three patients were infected with Mycobacterium tuberculosis.The infection involved humeral end,talus and surrounding joints in 14 patients,internal hemorrhoids in two patients,midfoot and interphalangeal joints in one patient,and humerus and metatarsophalangeal joints in two.The operation included three stages:the first stage was thorough debridement,supplemented with negative pressure closed drainage (VSD) and continuous washing to clarify the pathogenic bacteria;the second stage was to fill the bone defect with targeted antibiotic bone cement to prevent or treat infection;in the third stage,after filling the antibiotic bone cement for 3 months with no sign of local wound infection,the bone cement was taken out,and the bone reconstruction operation was performed by means of internal fixation and bone grafting.The flap survival and wound healing were observed,and the time of fracture healing was recorded.The American Orthopaedic Foot and Ankle Society (AOFAS) score and the Visual Analogue Score (VAS) were used to evaluate the improvement of the function of the foot and ankle before operation and at the last follow-up,and the bone healing was evaluated according to the radiographic union scale in tibial (RUST) fractures.Results The patients were followed up for 9-12 months [(11.1 ±1.0) months].Two patients with soft tissue defects caused by preoperative infection and necrosis received posterior tibial artery perforator flap and anterolateral thigh flap repair in the second stage,and the flaps all survived.The postoperative bone healing time was 3 7 months [(3.5 ± 1.4)months].Nineteen patients underwent three-stage surgery,and the ankle and foot wound or sinus tract were all healed,with no infection recurrence during follow-up.At the last follow-up,the AOFAS score was improved significantly from preoperative (36.3 s-12.1) points to (71.4 ± 5.7) points (P ＜ 0.05).The VAS was decreased significantly from preoperative (5.3 ± 1.2) points to (1.4 ± 0.9) points (P ＜ 0.05).The RUST bone healing score at the last follow-up was 8-12 points [(10.2 ± 1.1) points].Conclusion In treating the infective bone defects of foot and ankle,the three-stage Masquelet technique can effectively control infection,facilitate wound healing,promote bone union,and improve foot and ankle function.

Flap transplantation combined with Masquelet technique in the treatment of bone and soft defect / 中华显微外科杂志

Objective To explore the effect of the use of flap transplantation combined with Masquelet tech-nique in the repair of long bone accompanied with soft tissue defect. Methods The retrospective study includes 16 cases of bone defects over 6.0 cm combined with soft tissue defect from March,2013 to March,2016,13 males and 3 females, of which the ages range from 16 to 65 years. The length of bone defect ranged from 6.0 to 12.0 cm, with an average of 8.5 cm,while the wound defect ranged from 5.2 cm×3.5 cm to 16.0 cm×7.5 cm. There were 8 cases out of 16 involve an infection:3 cases of Staphylococcus aureus(including 1 MRSA),2 cases of Staphylococcus epidermidis, 2 cases of Enterobacter cloacae, and 1 case of Acinetobacter baumannii. The 1 stage surgery in all patients admitted to hospital after complete debridement and external fixation, the clean wounds with bone defect received antibiotic-impregnated bone cement filling operation and a flap transplantation or transposition directly after the debridement, but the infected wounds received vacuum sealing drainage treatment firstly, associated with adequate use of antibi-otics for 1-2 weeks and then the bone cement filling and flap transplantation with infection totally controlled.After 8-12 weeks, we conducted the secondary internal fixation surgery replacing antibiotic-impregnated bone cement with autogenic cancellous bone, vancomycin artificial bone as well as rhBMP-2. All the cases were followed for 6 to 18 months. Results All patients with primary surgery are effectively controlled after 1-4 weeks of anti-infection treat-ment exclusive of the case with MRSA.As the condition of the patient with MRSA relapse,we changed to convention-al treatment: placed a continuous irrigation and suction equipment instead of the bone cement filling, the wound healed completely without fistula formation of osteomyelitis in 6 months after the treatment of Ilizarov technique. All transplantation and transposition flaps survived. As for those who received a secondary bone graft operation, all achieved a bony union in a period of 4-6 months. Conclusion The combination of flap transplantation and Masquelet technique is an effective method to repair limb long bone and soft tissue defect currently.

Effects of Flavonoids of Rhizoma Drynariae on Formation of Blood Vessels in Induced Membrane by Masquelet Technique / 广州中医药大学学报

Objective To explore the effects of flavonoids of Rhizoma Drynariae on the formation of blood vessels in the induced membrane by Masquelet technique. Methods Seventy-two SD rats were randomly divided into 4 groups,namely model group,and high-,middle-and low-dose drug groups,18 rats in each group. Rat model of critical- sized femoral defect was built,and then polymethyl methacrylate (PMMA)bone cement spacer was inserted into the bone defect to induce the formation of membrane. From the first day after surgery , the rats in high-,middle-and low-dose drug groups were given gastric gavage of 0.44,0.22,0.11 g·kg-1·d-1 of Rhizoma Drynariae flavonoids, respectively, and the rats in the model group were given the same volume of normal saline. After 6-week medication,the pathologic features of bone cement- induced membrane were observed by Haematoxilin-Eosin(HE)staining,the contents of transforming growth factor(TGF)-β1 and vascular endothelial growth factor(VEGF)proteins in the induced membrane were tested by enzyme-linked immunosorbent assay (ELISA),and the mRNA levels of TGF-β1 and VEGF in the induced membrane were determined by real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results More blood vessels in the induced membrane of the high-dose group were found than those of the other groups under the light microscope. The protein and mRNA expression levels of TGF-β1 and VEGF in the induced membrane of the 3 drug groups were much higher than those of the model group(P < 0.05). Except for the VEGF mRNA expression level, the changes of other indexes were dose-dependent. Conclusion Flavonoids of Rhizoma Drynariae are effective on enhancing the protein and mRNA expression levels of TGF-β1 and VEGF in the induced membrane, and can accelerate the vascularization,which promotes the reconstruction of bone defect.

Clinical curative effect analysis of Masquelet technique for treatment of infected single-bone defect of forearm / 局解手术学杂志

Objective To evaluate the clinical curative effect of Masquelet technique in treatment of infected single-bone defect of forearm.Methods The clinical data of 18 cases of forearm bone defect caused by bone infection in our department from January 2011 to June 2016 were retrospectively analyzed.All the patients received standard treatment of Masquelet technique with two stage.Radical debridement,bone defect filling with antibiotic PMMA bone cement, and internal fixation were accomplished at the first stage, and treatment of bone defect with autologous iliac bone graft were accomplished at the second stage after 6 to 8 weeks at the end of the first stage.The infection control,fracture healing and complications of the 18 patients were observed.Results There was no complications such as infection recurrence,bone resorption,plate screw loosening occured.The functional recovery of 18 cases in this group was evaluated according to the Anderson evaluation scale.The results were excellent in 9 cases,satisfactory in 6 cases,unsatisfactory in 3 cases,and no failure.The satisfactory rate was 83.33%.Conclusion Controlling infection with local release of antibiotics from PMMA bone cement implantation through Masquelet technique, inducing autogenous membrane structure in the bone defect area,and then transplanting autologous cancellous bone for bone defect reconstruction repair treatment are effective in the treatment of infected single-bone defect of forearm.

Masquelet technique to treat post-traumatic osteomyelitis of long bones / 中华创伤骨科杂志

Long bone osteomyelitis often results from serious open fractures or some closed fractures.Its treatment is a clinical difficultly in orthopaedics.Masquelet is a new strategy for bone reconstruction,validated by surgeons in their treatment of acute bone loss,bone tumor and bone infection.It is carried out in 2 stages.At the first stage,infection was eliminated by radical debridement and placement of antibiotic bone cement into the defect,which induces a pseudomembrane to facilitate the growth of bone graft.At the second stage,reconstruction of the bone defect is performed by bone grafting in the membrance after removal of the bone cement.The unique characteristics of this technique arouse more and more attention recently.Therefore,we would like to present a review about this Masquelet technique dealing with post-traumatic osteomyelitis of long bones.