Induced membrane technique: a critical literature analysis and proposal for a failure classification scheme

Engineering the bone reconstruction surgery: the case of the masquelet-induced membrane technique

The reconstruction of large bone defects remains challenging for orthopedic surgeons. Autologous bone grafts (ABGs) are the gold standard treatment for limited size defects, but larger bone defects (> 5 cm) require the use of more sophisticated techniques, such as the Masquelet technique. Over the last three decades, the Masquelet or induced membrane technique (IMT) has become increasingly popular as it does not require high-precision microsurgery skills and the time taken to achieve bone consolidation is independent of the length of the defect. IMT is a two-stage procedure. In the first stage, a polymethylmethacrylate (PMMA) cement spacer is implanted into the bone lesion and a physiological immune reaction initiates the formation of a fibrotic induced membrane (IM) with both angiogenic and osteogenic properties. The second stage, performed several weeks later, involves removal of the spacer followed by the implantation of a standard ABG in the preserved IM cavity for subsequent bone repair. In this extensive review, we explain how the success of this surgical procedure can be attributed to the synergy of four key components: the inducer (the PMMA cement), the recipient (the IM), the effector (the bone graft) and the modulator (the mechanical environment). Conversely, we then explain how each key component can contribute to the failure of such treatment. Finally, we discuss existing or emerging innovative and biotechnology-oriented strategies for optimizing surgical outcome with respect to the four components of IMT described above.

Introducing the Pearl-String Technique: A New Concept in the Treatment of Large Bone Defects

The reconstruction of long bone defects after the primary traumatic, secondary infectious, or tumor-related loss of substance continues to represent a surgical challenge. Distraction osteogenesis using segmental transport, vascularized bone transfer, and the induced membrane technique (IMT) are established methods of reconstruction. IMT has become increasingly popular in recent decades due to its practicability, reproducibility, and reliability. At the same time, the original technique has undergone numerous modifications. The results are correspondingly heterogeneous. This article is intended to provide an overview of the current principles and modifications of IMT, outline the causes of failure of the IMT, and introduce the pearl-string technique (PST). The PST developed in our hospital is based on the pearl-string-like arrangement of thermodisinfected, decorticated femoral heads (TDFHs) in combination with a mechanically stable osteosynthetic construct. The TDFHs are biologically activated with either an RIA or autologous iliac crest bone graft. To gain a better understanding of these variations, the surgical technique of both procedures is illustrated step-by-step in this article.

Modern Management of Severe Open Fractures of the Extremities: The Role of the Induced Membrane Technique

➢ The administration of antibiotics, revascularization, effective initial debridement, stabilization, and dead-space management are important time-dependent, acute actions.➢ Following the adequate resuscitation of the patient and the local soft tissues, the first stage of the Masquelet technique is performed together with the definitive coverage of the soft-tissue defect.➢ The optimal time for the second stage (grafting of the bone defect) depends on the progress of the soft-tissue reconstruction and the overall state of the patient. It is usually at 6 to 14 weeks.➢ Bone graft involves cancellous autograft; depending on the volume of the defect, it can be acquired using different donor sites and methods and can be combined with cancellous allograft, bone substitutes, bone marrow aspirate, and inductive molecules.➢ Bone healing is independent of the size of the defect, assuming that revascularization of the graft material has not been disturbed.➢ The development of signs of a fracture-related infection in the clinical setting of a severe open fracture dictates surgical treatment and pathogen-specific antibiotics, debridement of the membrane and the surrounding soft tissues, and reinitiation of the staged process of limb salvage.➢ The results of staged management of severe open fractures with bone defects are reproducible and good.

Management of combat-related extremity injuries in modern armed conflicts

While the first conflicts of the 21st century involved asymmetric warfare in the fight against terrorism, recent geopolitical events require us to prepare for the possibility of high-intensity conflicts. Modern wounding agents mainly consist of explosive devices and high-velocity bullets. Every trauma surgeon must be familiar with the mechanisms of injury specific to armed conflicts. The initial care of these injuries is based on applying damage control surgery to save the patient's life, save their limb if possible and preserve their function. Blast injuries are the most common in modern armed conflicts; the resulting combination of severe injuries can be challenging to treat. Limb reconstruction involves a sequential strategy based on simple, reliable and reproducible techniques which can be used by non-specialized surgeons working in sometimes austere situations. LEVEL OF EVIDENCE: Expert opinion.

Masquelet technique including a multiperforated non-vascularized fibula graft for the reconstruction of massive post-traumatic bone defects in military practice

BACKGROUND

The management of extensive bone defects presents a significant challenge for military orthopedic surgeons, especially in the context of a high intensity conflict or when patients are fully treated in the field. The objective was to evaluate the induced membrane technique (IMT) including a multiperforated non-vascularized fibular graft (NVFG) for the reconstruction of massive bone defects performed in both the ideal conditions of military trauma centers and the austere environment of forward surgical units.

METHODS

A retrospective case study was conducted on patients who underwent the above procedure in various care settings between January 2019 and June 2023. Outcomes measured included the achievement of bone union, time to bone union, and the healing index (time to bone healing/length of reconstructed bone). Functional assessment was based on the Quick-DASH score and the lower extremity functional scale (LEFS).

RESULTS

Nine patients with a mean age of 37 years were included: five were managed in a role 4 medical treatment facility (MTF) and four in a role 2 MTF. Five patients had an infected bone defect before IMT application. After debridement, the mean bone defect length was 14 cm, and the mean bone defect volume was 190 cm3. The mean interval between stages was 15 weeks. The mean follow-up was 20 months. Bone union was achieved in 8/9 cases with a mean time of 8.1 months and a mean healing index of 0.58 month/cm. Only the patient with persistent humeral nonunion had a poor DASH-score. The mean LEFS was 68%.

CONCLUSIONS

In this small cohort, IMT including a multiperforated NVFG enabled successful reconstruction of massive bone defects in the femur, tibia, and humerus, even in the austere environment of forward surgical units, provided that prior infection control had been achieved.

Consolidation of the Anteromedial Aspect of the Tibia Is Inferior to the Other Areas in the Reconstruction of Critical-Sized Bone Defect of the Tibial Shaft Using the Induced Membrane Technique: An Analysis of 111 Serial Computed Tomography of 37 Patients

OBJECTIVES

To compare the consolidation quality between the anteromedial aspect of regenerated bone (AMRB) and the other areas of regenerated bone (TORB) following the induced membrane technique (IMT) for managing critical-sized tibial shaft bone defects, and determine the factors affecting consolidation quality in the AMRB.

METHODS

DESIGN

Retrospective comparative study.

SETTING

Academic Level I trauma center.

PATIENTS SELECTION CRITERIA

Included were patients who underwent IMT with only an intramedullary nail for tibial shaft segmental defects and serial computed tomography immediately, 6 months, and 1 year postoperatively.

OUTCOME MEASURES AND COMPARISONS

Comparison were made of regenerative bone volume, density, and corticalization between AMRB and TORB.

RESULTS

This study enrolled 37 patients with a mean age of 47.7 years (range 20-79). Twenty-eight (75.7%) patients were men. Postoperatively, the AMRB exhibited significantly more negative volumetric change than TORB at 0-1 year (-20.01% ± 25.59% vs. -13.32% ± 22.48%, P = 0.028), less positive density change 0-6 months (+197.84 ± 107.95 vs. +290.14 ± 131.74 Hounsfield unit (HU), P < 0.001) and 0-1 year (+377.51 ± 150.71 HU vs. +455.48 ± 135.04 HU, P < 0.001), and lower corticalization rate in 1 year (49.77% ± 29.42% vs. 82.27 ± 19.73%, P < 0.001). Significant factors included fracture-related infection (FRI) ( P = 0.047 and P = 0.048 at 0-6 months and 0-1 year, respectively) and longer defect length ( P = 0.032 and P = 0.020) for the negative volumetric AMRB changes; older age ( P = 0.004 and P = 0.016) for the AMRB negative density changes; higher percentage of mixed recombinant human bone morphogenetic protein-2 in graft material ( P = 0.013 in 0-6 months) for the AMRB positive density change; FRI ( P = 0.024) for the inferior corticalization rate of the AMRB; FRI ( P = 0.026 in 0-1 year), longer defect length ( P = 0.017 in 0-6 months), and higher mixed demineralized bone matrix percentage ( P = 0.010 in 0-1 year) for the difference in density change between the AMRB and TORB; higher mixed demineralized bone matrix percentage ( P = 0.023) for the difference between the AMRB and TORB in corticalization rates.

CONCLUSIONS

The tibial shaft's anteromedial aspects demonstrated significantly inferior consolidation after IMT, especially in terms of volume at 6 months, density at 6 months and 1 year, and corticalization at 1 year postoperatively.

LEVEL OF EVIDENCE

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

Efficacy and complications of the induced membrane technique for immediate bone reconstruction in complex hand injuries

PURPOSE

To report the radiological outcomes and complications of the Masquelet induced membrane technique (IMT) for acute bone reconstruction in complex hand injuries.

METHODS

We retrospectively reviewed 22 patients treated primarily by the IMT for bone defect of the phalanx and/or metacarpals bones in 26 injured digits. The median bone defect length was 17 mm (IQR 13-25). Given the severity and variability of the lesions, revision parameters focused on bone healing and postoperative complications.

RESULTS

At the median follow-up of nine months (IQR, 6-14 months), bone union was achieved in 25 digits (96%) with a median delay of three months (IQR, 2.5-3.5 months) after stage 2. Postoperative complications occurred in 11 of 26 digits requiring revision surgery in nine of 26 digits (35%). Soft tissue coverage failure and infection were the main complications. A patient underwent a late amputation through the metacarpophalangeal joint due to an uncontrolled bone infection.

CONCLUSIONS

Despite a significant rate of complications, bone reconstruction using the IMT is a reliable procedure for achieving bone healing of phalanx or metacarpal bone defects in complex hand injuries.

[Modified Masquelet technique : Technique of the induced membrane in the course of time]

The reconstruction of long bone defects as a result of primary traumatic, secondary infection or tumor-related loss of substance continues to represent a surgical challenge. Callus distraction via segment transport, vascularized bone transfer and the induced membrane technique (IMT) are established methods of reconstruction. In recent decades IMT has experienced increasing popularity due to its practicability, reproducibility and reliability. At the same time, the original technique has undergone numerous modifications. The results are correspondingly heterogeneous. This overview is intended to explain the basic principles of IMT and to provide an overview of the various modifications and their complications.

The induced membrane technique for the management of infected segmental bone defects

Aims

The aim of the present study was to assess the outcomes of the induced membrane technique (IMT) for the management of infected segmental bone defects, and to analyze predictive factors associated with unfavourable outcomes.

Methods

Between May 2012 and December 2020, 203 patients with infected segmental bone defects treated with the IMT were enrolled. The digital medical records of these patients were retrospectively analyzed. Factors associated with unfavourable outcomes were identified through logistic regression analysis.

Results

Among the 203 enrolled patients, infection recurred in 27 patients (13.3%) after bone grafting. The union rate was 75.9% (154 patients) after second-stage surgery without additional procedures, and final union was achieved in 173 patients (85.2%) after second-stage surgery with or without additional procedures. The mean healing time was 9.3 months (3 to 37). Multivariate logistic regression analysis of 203 patients showed that the number (≥ two) of debridements (first stage) was an independent risk factor for infection recurrence and nonunion. Larger defect sizes were associated with higher odds of nonunion. After excluding 27 patients with infection recurrence, multivariate analysis of the remaining 176 patients suggested that intramedullary nail plus plate internal fixation, smoking, and an allograft-to-autograft ratio exceeding 1:3 adversely affected healing time.

Conclusion

The IMT is an effective method to achieve infection eradication and union in the management of infected segmental bone defects. Our study identified several risk factors associated with unfavourable outcomes. Some of these factors are modifiable, and the risk of adverse outcomes can be reduced by adopting targeted interventions or strategies. Surgeons can fully inform patients with non-modifiable risk factors preoperatively, and may even use other methods for bone defect reconstruction.

The polymicrobial infection affects the infection recurrence rate (not failure) in treating femoral and tibial bone defects with the Masquelet technique-a comparative retrospective analysis of 54 patients with mono- and polymicrobial infections

INTRODUCTION

This study evaluated whether polymicrobial infection affects reoperation rates due to infection recurrence and treatment failure with the Masquelet technique in infected posttraumatic segmental bone defects of the femur and tibia.

METHODS

 We retrospectively analyzed patients treated between 2012 and 2021 in two trauma referral centers. We evaluated demographic data, injury, treatment, infection recurrence, failures, and bone healing rates according to whether the infection was mono- or polymicrobial. After uni-bivariate analysis between patients with polymicrobial and monomicrobial infection, we identified the variables associated with infection recurrence and failure through multivariate analysis.

RESULTS

 We analyzed 54 patients, 30 (55.55%) with tibial and 24 (44.44%) femoral segmental bone defects, with a mean follow-up of 41.7 ± 15.0 months. Forty-four (81.48%) presented monomicrobial, and 10 (18.51%) polymicrobial infections. Comparatively, the need for soft tissue reconstruction and the infection recurrence rate was significantly higher in patients with polymicrobial infections. There was no significant difference in the failure rate (20 vs. 6.81% p = 0.23). Multivariable logistic regression analysis identified the polymicrobial infection as the only independent variable associated with infection recurrence (Odds Ratio = 11.07; p = 0.0017).

CONCLUSION

 Our analysis suggests that polymicrobial infection is associated with a higher risk of infection recurrence in treating the femur and tibia segmental bone defects with the Masquelet technique. This information can help surgeons to inform patients about this and give them a realistic expectation of the outcome and the possibility of reoperation.

Treatment of infected bone defects with the induced membrane technique

Aims

This study aimed to evaluate the effectiveness of the induced membrane technique for treating infected bone defects, and to explore the factors that might affect patient outcomes.

Methods

A comprehensive search was performed in PubMed, Embase, and the Cochrane Central Register of Controlled Trials databases between 1 January 2000 and 31 October 2021. Studies with a minimum sample size of five patients with infected bone defects treated with the induced membrane technique were included. Factors associated with nonunion, infection recurrence, and additional procedures were identified using logistic regression analysis on individual patient data.

Results

After the screening, 44 studies were included with 1,079 patients and 1,083 segments of infected bone defects treated with the induced membrane technique. The mean defect size was 6.8 cm (0.5 to 30). After the index second stage procedure, 85% (797/942) of segments achieved union, and 92% (999/1,083) of segments achieved final healing. The multivariate analysis with data from 296 patients suggested that older age was associated with higher nonunion risk. Patients with external fixation in the second stage had a significantly higher risk of developing nonunion, increasing the need for additional procedures. The autografts harvested from the femur reamer-irrigator-aspirator increased nonunion, infection recurrence, and additional procedure rates.

Conclusion

The induced membrane technique is an effective technique for treating infected bone defects. Internal fixation during the second stage might effectively promote bone healing and reduce additional procedures without increasing infection recurrence. Future studies should standardize individual patient data prospectively to facilitate research on the affected patient outcomes.

4D Printing of Personalized-Tunable Biomimetic Periosteum with Anisotropic Microstructure for Accelerated Vascularization and Bone Healing

An ideal biomimetic periosteum is expected to wrap various bone surfaces to orchestrate an optimal microenvironment for bone regeneration, including facilitating local vascularization, recruiting osteoblasts, and mineralizing the extracellular matrix (ECM). To mimic the role of the natural periosteum in promoting bone repair, a 4D printing technique to inlay aligned cell sheets on shape-shifting hydrogel is used, containing biophysical signals and spatially adjustable physical properties, for the first time. The outer hydrogel layer endows the biomimetic periosteum with the ability to digitally coordinate its 3D geometry to match the specific macroscopic bone shape to maintain a bone healing microenvironment. The inner aligned human mesenchymal stem cells (hMSCs) layer not only promotes the migration and angiogenesis of co-cultured cells but also exhibits excellent osteogenic differentiation properties. In vivo experiments show that apart from morphing preset shapes as physical barriers, the aligned biomimetic periosteum can actively facilitate local angiogenesis and early-stage osteogenesis. Altogether, this present work provides a novel route to construct a personalized biomimetic periosteum with anisotropic microstructure by introducing a tunable shape to maintain the bone reconstruction microenvironment and this strategy can be extended to repair sophisticated bone defects.

Questions about Using the Induced Membrane Technique to Manage Cases of Congenital Tibial Pseudarthrosis

The induced membrane technique is an innovative approach for repairing critical bone defects and has been applied recently in patients with congenital pseudarthrosis of the tibia (CPT). CPT is frequently associated with neurofibromatosis type 1 (NF1). Here, we briefly describe the clinical results of the induced membrane technique in NF1-deficient patients with CPT and in an animal model of CPT. Furthermore, we discuss the hypotheses used to explain inconsistent outcomes for the induced membrane technique in CPT-especially when associated with NF1.

Feasibility evaluation of the induced membrane technique with structural autologous strip bone graft management of phalangeal and metacarpal segmental defects using radiography

PURPOSE

The purpose of this study was to explore the feasibility and evaluate the clinical outcomes of treatment for phalangeal and metacarpal segmental defects with the induced membrane technique and autologous structural bone grafting.

METHODS

Sixteen patients who sustained phalangeal or metacarpal bone segmental defects were treated by the induced membrane technique and autologous structural bone grafting from June 2020 to June 2021 at our center.

RESULTS

The average follow-up was 24 weeks (range, 12-40 weeks). Radiography demonstrated union of all bone grafts after an average of 8.6 weeks (range, 8-12 weeks). All incisions at donor and recipient sites demonstrated primary heal without infection complications. The mean visual analog scale score of the donor site was 1.8 (range, 0-5), with a good score in 13 cases and a fair score in 3. The mean total active motion of the fingers was 179.9°.

CONCLUSIONS

The feasibility of the induced membrane technique and structural treatment with a cylindrical bone graft for segmental bone defects of the metacarpal or phalanx is demonstrated by follow-up radiography results. The bone graft provided much more stability and structural support in the bone defects, and the bone healing time and bone union rate were ideal.

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.

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.

Treatment of tibial bone defects: pilot analysis of direct medical costs between distraction osteogenesis with an Ilizarov frame and the Masquelet technique

Purpose

The cost implications of limb reconstruction techniques have not been adequately investigated. Aim of this pilot study was to compare the direct medical cost of tibial bone defects managed with distraction osteogenesis–Ilizarov method (ILF), or with Masquelet technique (MIF).

Methods

Data of 20 random patients treated in a single centre were analysed. Inclusion criteria included acute tibial defects, or post-debridement of nonunions with complete follow-up and successful union. The endpoint of clinical efficacy was the time-to-defect union. Comparisons were made between equally sized subgroups (ILF vs. MIF).

Results

The average defect length was 5.6 cm (2.6–9.6 cm). The overall cost of 20 cases reached £452,974 (mean £22,339, range £13,459–£36,274). Statistically significant differences favoring the MIF were found regarding the average time-to-union; number of surgeries, of admissions and follow-up visits, as well as the mean intraoperative cost (£8857 vs. £14,087). These differences lead to significant differences of the mean cost of the overall treatment (MIF £18,131 vs. ILF £26,126). Power analysis based on these data indicated that 35 patients on each group would allow detection of a 25% difference, with an alpha value of 0.05 and probability (power) of 0.9.

Conclusions

The results and analysis presented highlight factors affecting the high financial burden, even in a best-case scenario, this type of surgery entails. Larger pivotal studies should follow to improve the cost efficiency of clinical practice.

Masquelet technique in military practice: specificities and future directions for combat-related bone defect reconstruction

Because of its simplicity, reliability, and replicability, the Masquelet induced membrane technique (IMT) has become one of the preferred methods for critical bone defect reconstruction in extremities. Although it is now used worldwide, few studies have been published about IMT in military practice. Bone reconstruction is particularly challenging in this context of care due to extensive soft-tissue injury, early wound infection, and even delayed management in austere conditions. Based on our clinical expertise, recent research, and a literature analysis, this narrative review provides an overview of the IMT application to combat-related bone defects. It presents technical specificities and future developments aiming to optimize IMT outcomes, including for the management of massive multi-tissue defects or bone reconstruction performed in the field with limited resources.

Effect of Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) with Hydroxyapatite Carrier in Induced Membrane Technique: A Retrospective Propensity Score-Matched Study

OBJECTIVES

To determine the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) with hydroxyapatite (HA) carrier augmentation in managing critical-sized bone defect (CSBD) with induced membrane technique (IMT).

DESIGN

Retrospective comparative study.

SETTING

Academic level I trauma center.

PATIENTS/PARTICIPANTS

The study included 14 patients who underwent rhBMP-2 with HA carrier (rhBMP-2/HA) augmentation in IMT for managing CSBD (BMP group). Moreover, 14 patients who underwent IMT without rhBMP-2 augmentation were matched by propensity score analysis (non-BMP group).

INTERVENTION

IMT with or without rhBMP-2/HA augmentation.

MAIN OUTCOME MEASUREMENT

Changes in quality and quantity measurements of grafted bone to regenerated bone using serial computed tomography.

RESULTS

In the BMP and non-BMP groups, the changes in densities from grafted bone to regenerated bone were +379.63 Hounsfield unit and +248.55 Hounsfield unit (P = 0.034), changes in dense bone percentage were +37.52% and +23.31% (P = 0.027), corticalization rates under the plate were 79.70% and 39.30% (P = 0.007), changes in volume were -20.77% and -23.35% (P = 0.812), union rates were 85.71% and 78.57% (P = 0.622), numbers of patients requiring additional procedures were 4 and 3 (P = 0.663), and time to union were 316.3 and 585.45 days (P = 0.040), respectively.

CONCLUSIONS

RhBMP-2/HA augmentation increases the density of regenerated bone, enhances corticalization under the plate, and shortens the time to union while managing CSBD with IMT.

LEVEL OF EVIDENCE

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

Induced membrane technique for acute bone loss and nonunion management of the tibia

Objectives:

To report our experience and clinical results of using the Masquelet technique for the treatment of tibial nonunions and acute traumatic tibial bone defects.

Design:

Retrospective study of prospectively collected data (Level IV).

Setting:

Level I trauma center in the UK.

Patients/Participants:

Consecutive patients with tibial nonunions and open fractures associated with bone loss.

Intervention: Two-stage Masquelet Procedure for the tibia.

Main Outcome Measurements:

Clinical and imaging assessment at 6 weeks, 3,6,9,12 months, or until pain-free mobilization and union.

Results:

There were 17 eligible patients, with a mean size of bone defect of 6 cm (range, 4–8 cm) and an 88.2% union rate at a mean of 8 months (range 5–18 months). Mean range of motion was 95 degrees of knee flexion (range 80°–130°). All patients but 2 returned to their previous occupation.

Conclusions:

The Masquelet technique is simple, effective, and has a high rate of success for the management of a variety of situations including acute bone loss or infected nonunions and is associated with a low incidence of complications.

Effects of PMMA spacer loaded with varying vancomycin concentrations on bone regeneration in the Masquelet technique

Whether antibiotics should be included remains greatly debated in Masquelet technique. This study intended to determine the effect of polymethyl methacrylate (PMMA) spacer loaded with different vancomycin concentrations on bone defect repair. Hollow cylindrical spacers consisting of PMMA and varying vancomycin concentrations (0, 1, 2, 4, 6, 8, and 10 g) were prepared. Critical bone defects of rabbits were created at the radial shaft, and spacers were implanted and subsequently intramedullary fixed with retrograde Kirschner’s wires (n = 4 for each vancomycin concentration). After 4 weeks, the induced membranes were opened and cancellous allografts were implanted into the defects. Eight weeks post-operatively, the results of X-ray, histology, and micro-CT revealed that some cortical bone was formed to bridge the gap and the bone marrow cavity was formed over time. Quantitatively, there was more new bone formation in the groups with a relatively lower vancomycin concentration (1–4 g) compared with that in the groups with a higher vancomycin concentration (6–10 g). Our findings suggested that PMMA spacers loaded with relatively lower vancomycin concentrations (1–4 g) did not interfere with new bone formation, whereas spacers loaded with relatively higher vancomycin concentrations (6–10 g) had negative effects on bone formation.

Case report: Restoration of an open 12 cm femoral defect treated with the Masquelet technique in a 20-year-old polytrauma

Infected post-traumatic femoral defects are challenging to treat, and limited options exist. The case of a 20-year-old polytrauma male who sustained a segmental femur fracture involving the femoral neck, distal femur and an intermediate diaphyseal bone defect of 12 cm is presented. The patient declined a long-term frame in his femur. The 2-stage Masquelet procedure resulted in successful outcome with limb preservation.

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Femoral bone defects are challenging to treat.

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Patients do not tolerate bone transport well in this area.

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Successful management of a 12cm femoral bone defect is reported in a 20-year old patient using the Masquelet technique.

Forearm segmental bone defect: Successful management using the Masquelet Technique with the aid of 3D printing technology

The management of forearm nonunion is challenging for orthopaedic surgeons because the forearm is a unique anatomical segment in which all the bones and structures involved embody a complex functional unit. Therefore, when treating such a complex condition, the surgeon must focus not only on bone healing but also on the restoration of the native anatomy in order to replicate the normal relationship between the bones and all the surrounding structures and thus the full function of the forearm, the elbow and the wrist.

Here we report the case of a 53-year-old patient with a left forearm deformity due to an atrophic nonunion of the ulna and a malunion of the radius, which was successfully managed with the use of the Masquelet technique associated with a corrective osteotomy of the radius, performed with the aid of a 3D model.

Management of segmental bone defects of the upper limb: a scoping review with data synthesis to inform decision making

PURPOSE

Injuries to the long bones of the upper limb resulting in bone defects are rare but potentially devastating. Literature on the management of these injuries is limited to case reports and small case series. The aim of this study was to collate the most recent published work on the management of upper limb bone defects to assist with evidence based management when confronted with these cases.

METHODS

Following a preliminary search that confirmed the paucity of literature and lack of comparative trials, a scoping review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) was conducted. A literature search of major electronic databases was conducted to identify journal articles relating to the management of upper limb long bone defects published between 2010 and 2020.

RESULTS

A total of 46 publications reporting on the management of 341 patients were reviewed. Structural autograft, bone transport, one-bone forearm and the induced membrane technique were employed in an almost equal number of cases. The implemented strategies showed similar outcomes but different indications and complication profiles were observed.

CONCLUSION

Contemporary techniques for the management of post-traumatic upper limb bone defects all produce good results. Specific advantages, disadvantages and complications for each modality should be considered when deciding on which management strategy to employ for each specific patient, anatomical location, and defect size.