Induced Membrane Technique Research Articles

Knowledge mapping of induced membrane technique: a scientometric study from 2004 to 2023

BackgroundThe induced membrane technique (IMT) is a two-step procedure used for reconstructing segmental bone defects in the limbs. The osteogenic mechanism after bone grafting using IMT remains unclear, and efforts to modify the original techniques are limited to the investigative phase. Therefore, reviewing existing knowledge and identifying hotspots and new trends in IMT is critical.MethodsWe retrieved reviews and articles associated with IMT published between 2004 and 2023 from the Web of Science Core Collection (WoSCC). The keywords included induced membrane technique, guided bone regeneration, bone defect reconstruction, bone graft, stem cells, Masquelet technique, management of bone defects, and scaffold. HistCite, VOSviewer, CiteSpace, and R-bibliometrics were used for scientometric analysis.ResultsA total of 1019 publications from 374 academic journals with 33,995 co-cited references by 2,331 institutions from 65 countries or regions were included. China (n = 235) and the United States (n = 215) were the most productive countries, with Shanghai Jiao Tong University producing the most number of publications (n = 18). Journal Injury [co-citations = 1774; impact factor (IF) 2022 = 2.5] published the most manuscripts, while Masquelet AC and Giannoudis PV published literature with a significant influence on IMT, showing more co-citations (n = 727; n = 355). Two preface hotspots of IMT focused on investigating the microscopic mechanism (such as the membrane supporting graft-to-bone union and the role of inflammatory cells) and developing new techniques to improve IMT (such as bone tissue engineering and new drugs).ConclusionThis study comprehensively reviewed the literature about IMT published in the last 20 years using qualitative and quantitative methods, providing valuable information for researchers investigating IMT.

Induced membrane technique for malignant bone tumours of the humerus.

The aim of this study was to report on mid- to long-term results following large humeral tumoral resection and reconstruction with the induced-membrane technique in skeletally immature patients suffering from primary malignant bone tumours. A retrospective analysis identified all children who underwent the two stages of a humeral reconstruction using the induced-membrane technique for primary malignant humerus tumours between 2002 and 2020. Functional assessment was conducted by an independent observer using the Musculoskeletal Tumor Society (MSTS) scoring system for the upper limb. Radiological assessment was performed by two independent observers and the healing index was calculated (i.e., months/cm). Eight adolescents (5 osteosarcomas and 3 Ewing sarcoma), with a mean age of 14.2 years (SD = 2.7), were included. The mean length of the bone resection was 17.4cm (SD = 3.8), and the mean delay of the resection and reconstruction stages was 9.4 months (SD = 4). The mean follow-up was 6.6 years (SD = 4.3). The mean MSTS score was 77.4% and the global average healing index was 1.04 months/cm (SD = 2.2). Four complications (i.e., prominence device, fracture, aseptic pseudarthrosis, radial palsy) and one local recurrence were observed in four patients, requiring four unplanned surgical procedures in three patients. One patient died fourteen years after the initial treatment due to a lung recurrence. The induced-membrane technique is an effective and safe alternative for reconstructing large humeral bone defects after tumour resection in adolescents. Although this is a two-stage technique, it gives good functional results comparable to other strategies found in the literature. IV.

Treatment of infected humeral shaft nonunion and presumed aseptic nonunion with positive intraoperative cultures: a retrospective single-center study.

The management of infected humeral shaft nonunion (HSN) remains challenging due to the lack of consensus and the potential for occult infection. The aim of this study was to evaluate a surgical strategy based on a two-stage treatment for suspected infection or a one-stage treatment for infection diagnosed retrospectively based on systematic bacteriological sampling. We retrospectively reviewed 16 patients with a median age of 36 years who were treated for septic HSN: 9 patients underwent a two-stage procedure using the induced membrane technique, and 7 patients were treated in a single stage. Revision parameters included achieving bone union, its time frame, and a functional assessment based on joint motion and the Quick-DASH score. At a median follow-up of 47.5 months, 12 out of 16 patients were cured with acquired bone union and no septic recurrence. The median time to bone union was 5.5 months. Smoking and previous surgeries were adverse factors for bone healing. Radiological and functional outcomes were comparable between patients treated in a single stage and those treated in two stages. This study confirms the relevance of one-stage surgery for HSN with occult infection and the value of systematic bacteriological sampling during the revision of humeral diaphyseal osteosynthesis.

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

The reconstruction of long bone defects as aresult of primary traumatic, secondary infection or tumor-related loss of substance continues to represent asurgical 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 management of critical bone defects: outcomes of a systematic approach

BackgroundThe reconstruction of segmental long bone defects remains one of ‘The holy grails of orthopaedics’. The optimal treatment of which remains a topic of great debate. This study aimed to evaluate the outcomes following the management of critical-sized bone defects using a classification-based treatment algorithm.MethodsA retrospective review of all patients undergoing treatment for segmental diaphyseal defects of long bones at a tertiary-level limb reconstruction unit between January 2016 and December 2021, was performed. The management of the bone defect was standardised as per the classification by Ferreira and Tanwar (2020).ResultsA total of 96 patients (mean age 39.8, SD 15.2) with a minimum six months follow-up were included. Most bone defects were the result of open fractures (75/96) with 67% associated with Gustilo-Anderson IIIB injuries. There was a statistical difference in the likelihood of union between treatment strategies with more than 90% of cases undergoing acute shortening and bone transport achieving union and only 72% of cases undergoing the induced membrane technique consolidating (p = 0.049). Of those defects that consolidated, there was no difference in the time to bone union between strategies (p = 0.308) with an overall median time to union 8.33 months (95% CI 7.4 – 9.2 months). The induced membrane technique was associated with a 40% risk of sepsis.ConclusionThis study reported the outcomes of a standardised approach to the management of critical-sized bone defects. Whilst overall results were supportive of this approach, the outcomes associated with the induced membrane technique require further refinement of its indications in the management of critical-sized bone defects.Level of evidence4.

Bone Transport through Induced Membrane Technique versus Conventional Bone Transport Technique in Management of Bone Defects of Lower Limbs

Abstract Objectives To assess whether Bone transport through induced membrane (BTM) has better outcomes regarding docking site union and infection recurrence than conventional bone transport (BT) or not in the treatment of infected lower limb long bones defects. Methods A prospective randomized controlled study in a single institution was conducted. A total of 30 patients with infected non united fractures of long bones of lower limbs were divided into 15 patients (10 femurs, 5 tibias) treated by BTM and 15 patients (3 femurs,12 tibias) treated by BT. The outcome measures includes external fixation time (EFT), external fixation index (EFI), docking time (DT), bone and functional outcomes evaluated by the Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system, postoperative complications evaluated by Paley classification and number of additional operations. Results The mean docking time (DT) was significantly lower in BTM group in comparison to BT group (3.67 ± 0.82 months vs 4.80 ± 0.86 months respectively) (p value 0.001). Docking site nonunion and infection recurrence were significantly lower in BTM group in comparison to BT group (0% vs 40% respectively) (p value 0.02) and (0% vs 33.3% respectively) (p value 0.04). Mean number of additional operations per patient was significantly lower in BTM group in comparison to BT group (0 vs 0.80 ± 1.08 operations respectively) (p value 0.01) Conclusion Both BTM and BT achieved satisfactory postoperative bone and functional outcomes in patients with infected long bones defects of lower limbs, while BTM had significantly faster docking site union, lower incidence of postoperative complications including docking site nonunion and infection recurrence rates and lower number of additional operations needed at the expense of 2 staged procedure in comparison to BT.

A Novel Method to Assess Healing of Segmental Bone Defects using the Induced Membrane Technique.

Clinical concerns exist regarding the quality of bony consolidation in the context of the induced membrane technique. This study evaluates the clinical process of bone grafting in the second stage of induced membrane bone union in patients with tibial bone defects to infer the possibility of non-union and establish a reliable and effective evaluation method combined with computed tomography (CT) to assess fracture healing. Patients with tibial bone defects who underwent the induced membrane technique at our hospital between February 2017 and February 2020 were retrospectively analyzed. The Hounsfield unit (HU) values of the patients were evaluated at different times during the second stage of bone grafting. Bone healing at the boundary value of the 120 HU output threshold (-1024 HU-3071 HU) was directionally selected, and the changes in the growth volume of union (new bone volume [selected according to HU value]/bone defect volume) were compared with analyzing individual class bone union. Method 1 involved X-rays revealing that at least three of the four cortices were continuous and at least 2 mm thick, with the patient being pain free. For Method 2, new bone volume (selected according to HU value/bone defect volume) at the stage was compared with analyzing individual class healing. Receiver operating characteristic curve analysis was used for Methods 1 and 2. A total of 42 patients with a segmental bone defect with a mean age of 40.5 years (40.5 ± 8.3 years) were included. The relationship between bone graft volume and time variation was analyzed by single factor repeated variable analysis (F = 6.477, p = 0.016). Further, curve regression analysis showed that the change in bone graft volume over time presented a logarithmic curve pattern (Y = 0.563 + 0.086 × ln(X), Ra2 = 0.608, p = 0.041). ROC curve analysis showed that Method 2 is superior to Method 1 (AUC: 86.3% vs. 68.3%, p < 0.05). The induced membrane technique could be used to treat traumatic long bone defects, with fewer complications and a higher healing rate. The proposed imaging grading of HU (new bone volume/bone defect volume) can be used as a reference for the quality of bony consolidation with the induced membrane technique.

The Masquelet induced membrane technique with PRP-FG-nHA/PA66 scaffold can heal a rat large femoral bone defect

BackgroundMasquelet membrane induction technology is one of the treatment strategies for large bone defect (LBD). However, the angiogenesis ability of induced membrane decreases with time and autologous bone grafting is associated with donor site morbidity. This study investigates if the PRP-FG-nHA/PA66 scaffold can be used as a spacer instead of PMMA to improve the angiogenesis ability of induced membrane and reduce the amount of autologous bone graft.MethodsPlatelet rich plasma (PRP) was prepared and PRP-FG-nHA/PA66 scaffold was synthesized and observed. The sustained release of VEGFA and porosity of the scaffold were analyzed. We established a femur LBD model in male SD rats. 55 rats were randomly divided into four groups depending on the spacer filled in the defect area. “Defect only” group (n = 10), “PMMA” group (n = 15), “PRP-nHA/PA66” group (n = 15) and “PRP-FG-nHA/PA66” group (n = 15 ). At 6 weeks, the spacers were removed and the defects were grafted. The induced membrane and bone were collected and stained. The bone formation was detected by micro-CT and the callus union was scored on a three point system.ResultsThe PRP-FG-nHA/PA66 scaffold was porosity and could maintain a high concentration of VEGFA after 30 days of preparation. The induced membrane in PRP-FG-nHA/PA66 group was thinner than PMMA, but the vessel density was higher.The weight of autogenous bone grafted in PRP-FG-nHA/PA66 group was significantly smaller than that of PMMA group. In PRP-FG-nHA/PA66 group, the bone defect was morphologically repaired.ConclusionThe study showed that PRP-FG-nHA/PA66 scaffold can significantly reduce the amount of autologous bone graft, and can achieve similar bone defect repair effect as PMMA. Our findings provide some reference and theoretical support for the treatment of large segmental bone defects in humans.

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

BackgroundChildren's bone loss of limbs represents a significant challenge for surgeons, especially given that children are growing individuals. In the pediatric population, we compared bone reconstruction using vascularized fibula flaps with the induced membrane technique. The primary purpose of this study was to evaluate the delay and quality of consolidation. Methods.Data from patients who underwent limb reconstruction using either the fibula flap or the induced membrane were retrospectively collected from files across two centers. Perioperative and long-term complications were documented, along with functional and aesthetic outcome. ResultsBetween 2004 and 2020, 31 children underwent limb reconstruction using a fibula flap, and 13 patients were treated using the induced membrane technique. The etiologies included 76% tumors, 20% congenital pseudarthroses, and 3.7% infections. The median size of the bone resection was 12.5cm (range: 1.8 to 31cm). The median time to consolidation after free fibula flap transfer was 10 months (range: 2 to 55 months) versus 7.5 months (range: 1 to 64 months) for the Masquelet technique (p=0.54). Limb length inequality occured in 52% of fibula cases and 39% of the induced membrane cases (p=0.55). ConclusionsBoth of free fibula flap and the induced membrane technique are effective options for bone reconstructing long bones in children. These techniques yield good functional outcomes and have comparable consolidation times.

Improvements in Pediatric Bone Loss Reconstruction With the Induced Membrane Technique.

The induced membrane technique is now widely used for pediatric diaphyseal bone loss due to various etiologies. Although consolidation rates remain satisfactory, complications, and healing delays may occur requiring additional procedures. We studied a series of induced membrane bone reconstructions in which the second stage included an embedded endomembranous non vascularized fibular shaft, in addition to iliac bone grafts. The purpose of this study was to analyze the results in terms of bone consolidation and complications. This is a retrospective comparative and multicentric study of 32 children with large bone loss treated with the induced membrane reconstruction technique. Patients were divided into 2 groups according to the graft used during the second stage. The first group (G1) of 16 patients had a nonvascularized fibula embedded inside the membrane in addition with the corticocancellous grafts from the iliac crest. The second group (G2) of 16 patients underwent reconstruction using the original technique, with iliac crest graft only. The 2 groups were similar in terms of etiologies of bone loss and follow-up (mean: 44mo for G1 and 49mo for G2). Mean bone losses were 15.4cm (range: 2 to 25; SD: 5.6) for G1 and 10.6cm (range: 3 to 19; SD: 5.2) for G2. In the first group, all patients healed primarily, with a mean time of 5.9 months (range: 4 to 8; SD: 1.6). In the second group, 2 of 16 patients did not healed; for the others 14, healing mean time was 6.9 months (range: 3 to 12; SD: 2.7). The short-term and long-term complications rates were 38% to 19% for G1 and 50% to 31% for G2, respectively. Regarding the donor site, the fibulas reconstructed spontaneously with a mean time of 4.8 months (range: 3 to 6; SD: 1.2). The integration of a nonvascularized fibula during the second stage of the induced membrane technique appears to improve the consolidation rate in the pediatric population. Level III-Retrospective comparative study.

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

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. 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. 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. 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.

Activated allograft combined with induced membrane technique for the reconstruction of infected segmental bone defects

This study was desinged to evaluate the efficacy and safety of activated allograft combined with the induced membrane technique for reconstruction of infected segment bone defects of lower limbs. A retrospective analysis was conducted on 19 patients from May 2015 to February 2017. After debridements, the bone defects were filled with antibiotic bone cement to form the induced membrane. Autologous mesenchymal stem cells were seeded onto allografts to construct activated allograft, which was implanted into the induced membrane after infection was controlled. The clinical efficacy and complications were observed. 19 patients with 20 infected segment bone defect were evaluated. The average deficit size was 11.08 (4–17) cm in length. After a mean follow-up of 71.84 (61–82) months, bone union was achieved in 16 patients (17 sites), resulting in a final union rate of 84.21% (16/19 patients). The average bone union time was 10.18 (5–28) months. There were 2 patients with recurrence of infection, 3 patients with graft absorption, and 1 patient with malunion due to implant breakage. There were no graft-related complications. This study provides clinical significance for the treatment of patients with insufficient autologous bone.

THE MANAGEMENT OF CRITICAL BONE DEFECTS: OUTCOMES OF A SYSTEMATIC APPROACH

IntroductionThe reconstruction of segmental long bone defects remains one of the holy grails of orthopaedic surgery. The optimal treatment of which remains a topic of great debate. This study aimed to evaluate the outcomes following the management of critical-sized bone defects using a classification-based treatment algorithm.Materials &amp; MethodsA retrospective review of all patients undergoing treatment for segmental diaphyseal defects of long bones at a tertiary-level limb reconstruction unit was performed. The management of the bone defect was standardised as per the classification by Ferreira and Tanwar (2020).ResultsA total of 96 patients (mean age 39.8, SD 15.2) with a minimum six months follow-up were included. Most bone defects were the result of open fractures (75/96) with 67% associated with Gustilo-Anderson IIIB injuries. There was a statistical difference in the likelihood of union between treatment strategies with more than 90% of cases undergoing acute shortening and bone transport achieving union and only 72% of cases undergoing the induced membrane technique consolidating (p=0.049). Of those defects that consolidated, there was no difference in the time to bone union between strategies (p=0.308) with an overall median time to union 8.33 months (95% CI 7.4 — 9.2 months). The induced membrane technique was associated with a 40% risk of sepsis.ConclusionsThis study reported the outcomes of a standardised approach to the management of critical-sized bone defects. Whilst overall results were supportive of this approach, the outcomes associated with the induced membrane technique require further refinement of its indications in the management of critical-sized bone defects.

Induced-membrane technique for lower limb reconstruction after malignant bone tumour resection in paediatric patients: Complication and re-operation rates

BackgroundThe objective of this study was to assess the complication and re-operation rates, evaluate the risk of non-union, and describe the functional outcomes at last follow-up in children and adolescents after lower-limb malignant tumour resection and reconstruction using the induced-membrane technique. HypothesisWeight-bearing resumption 6 weeks after the second stage of the induced-membrane procedure promotes bone healing. Material and methodsThe study included 13 patients (9 with osteosarcoma, 3 with Ewing's sarcomas, and 1 with alveolar sarcoma) managed between 2000 and 2020 by oncological femoral or tibial resection followed, at a distance from adjuvant chemotherapy, by reconstruction using the induced-membrane technique. Non-union was the primary outcome measure and the MusculoSkeletal Tumor Society (MSTS) lower-limb functional score was the secondary outcome measure. Mean follow-up was 6.1 years (range, 2.0–12.7). At last follow-up, mean age was 18.1 years (range, 11.0–26.0) and the mean MSTS score was 66.6% (37.0–93.0%). ResultsAfter the second reconstruction stage, 8 complications developed in 6 patients (46%). Either a complication or limb-length inequality required 12 re-operations in 8 patients (61.5%). Non-union occurred after reconstruction in 5 (38.5%) patients. Early resumption of 50% weight-bearing 6 weeks after reconstruction was associated with bone healing (p=0.02). ConclusionThe non-union rate was 38.5%. Partial, 50% weight-bearing with two elbow crutches and an orthosis, if allowed by construct stability, may promote bone healing. Level of evidenceIV.

The Impact of Defect Size on Bone Healing in Critical-Size Bone Defects Investigated on a Rat Femur Defect Model Comparing Two Treatment Methods.

Critical-size bone defects up to 25 cm can be treated successfully using the induced membrane technique established by Masquelet. To shorten this procedure, human acellular dermis (HAD) has had success in replacing this membrane in rat models. The aim of this study was to compare bone healing for smaller and larger defects using an induced membrane and HAD in a rat model. Using our established femoral defect model in rats, the animals were placed into four groups and defects of 5 mm or 10 mm size were set, either filling them with autologous spongiosa and surrounding the defect with HAD or waiting for the induced membrane to form around a cement spacer and filling this cavity in a second operation with a cancellous bone graft. Healing was assessed eight weeks after the operation using µ-CT, histological staining, and an assessment of the progress of bone formation using an established bone healing score. The α-smooth muscle actin used as a signal of blood vessel formation was stained and counted. The 5 mm defects showed significantly better bone union and a higher bone healing score than the 10 mm defects. HAD being used for the smaller defects resulted in a significantly higher bone healing score even than for the induced membrane and significantly higher blood vessel formation, corroborating the good results achieved by using HAD in previous studies. In comparison, same-sized groups showed significant differences in bone healing as well as blood vessel formation, suggesting that 5 mm defects are large enough to show different results in healing depending on treatment; therefore, 5 mm is a viable size for further studies on bone healing.

Induced Membrane Technique Combined with Surgical Lengthening of an Humerus Defect Secondary to Chronic Osteomyelitis: Case Report

Surgical management of long bone defects remains a considerable challenge for orthopedic surgeons, particularly in septic conditions. We present the case of an 8-year-old girl with a history of chronic osteomyelitis in the left humerus, referred to us following a pathologic fracture, initially managed with humeral osteosynthesis and grafting. Subsequently, the induced membrane technique was employed for pseudarthrosis after a recurrent fracture. Following consolidation, significant humeral shortening was observed, necessitating surgical lengthening using an external fixator, resulting in a satisfactory final outcome.

Infected humeral shaft nonunion treatment with the induced membrane technique and a novel fixation construct: a case report.

A 51-year-old woman with an infected left humeral shaft recalcitrant nonunion presented 3 years after initial injury. This case report focuses on the staged treatment of a 17-centimeter (cm) humeral shaft nonunion with the induced membrane technique (IMT) using a unique fixation construct of dual locked plating around a humeral nail to provide long-lasting fixation and allow for bone graft consolidation. Large segmental bone loss of the humerus can be treated with the IMT using nail-plate fixation constructs that allow for early mobilization, increased time for bone graft consolidation before hardware failure, and less frequent follow-up.

Induced membrane technique with plate fixation has a lower complication rate than bone transport over a plate for segmental tibial defects larger than 5cm.

The treatment of segmental tibial bone defects remains a surgical challenge. While Bone Transport (BT) and Induced Membrane Technique (IMT) are effective strategies for regenerating bone, there are few comparative studies between them. This investigation undertakes a comparative analysis of BT and IMT for large segmental tibial defects stabilised through plate fixation. Patients with segmental tibial defects exceeding 5cm were prospectively enrolled from 2008 to 2021 in a single institution, with a minimum follow-up duration of two years. All patients underwent either BT or IMT with plate fixation of the tibia. Procedural success, primary union as well as bone and functional outcome scores were compared. Complications, including non-unions, joint contractures and deep infections requiring surgical intervention, were also compared. 41 patients were recruited in total. 28 patients underwent Bone Transport Over a Plate (BTOP), while 13 patients underwent IMT with Plate fixation (IMTP). The procedural success rate trended higher in IMTP compared to BTOP (100% vs. 85.7%). The primary union rate also trended higher in IMTP compared to BTOP (92.3% vs. 79.2%). BTOP and IMTP achieved similar rates of satisfactory bone outcome scores (78.6% vs. 84.6%) and functional outcome scores (75% vs. 76.5%). There was no statistical difference between procedural success, primary union, bone and functional outcome scores. The complication rate in BTOP was 78.6% (22 of 28), including five docking site or regenerate non-unions, eight deep infections and nine joint contractures. IMTP had a 38.5% (5 of 13) complication rate, including one non-union, two deep infections and two joint contractures. The complication rate was 2.04 times higher in BTOP compared to IMTP (p = 0.0117). BTOP and IMTP are both equally effective techniques for regenerating bone in large tibial bone defects. However, IMTP may be a safer procedure than BTOP, with a lower probability of requiring additional procedures to address complications.

Systematic literature review of in vivo rat femoral defect models using biomaterials to improve the induced membrane technique: a comprehensive analysis.

The aim of this study was to conduct a systematic literature review analyzing the results of in vivo rat femoral defect models using biomaterials for improving the induced membrane technique (IMT). Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the PubMed, Embase, and Web of Science databases were searched. Inclusion criteria were studies reporting results of the IMT in in vivo rat femoral critical-sized defect models using a biomaterial possibly combined with molecules. Methodologic quality was assessed with the Animal Research: Reporting In Vivo Experiments guidelines. Twenty studies met the inclusion criteria. Femoral stabilization with plate and screws was the most frequent. Histologic, biomechanical, and/or radiologic analyses were performed. In two-stage strategies, the PMMA spacer could be associated with bioactive molecules to enhance IM growth factor expression and improve bone formation. Modulating the roughness of spacers could increase IM thickness and accelerate its formation. In one-stage strategies, human tissue-derived membranes combined with bone grafting achieved bone formation comparable to a standard IMT. All calcium phosphate grafts seemed to require a functionalization with growth factors or bone marrow mononuclear cells to improve outcomes compared with non-functionalized grafts. This systematic review described the main parameters of the in vivo rat femoral defect models using biomaterials to improve the induced membrane technique. Although the studies included had several methodological limitations that may limit the scope of these conclusions, one- and two-stage strategies reported promising results with biomaterials to improve the IMT.

THE INDUCED MEMBRANE TECHNIQUE IMPROVES THE HEALTH-RELATED QUALITY OF LIFE IN PATIENTS WITH A POST-TRAUMATIC LONG BONE NONUNION

The optimal treatment strategy for post-traumatic long bone non-unions is subject of an ongoing discussion. At the Maastricht University Medical Center (MUMC+) the induced membrane technique is used to treat post-traumatic long bone non-unions. This technique uses a multimodal treatment algorithm involving bone marrow aspirate concentrate (BMAC), the reamer-irrigator-aspirator (RIA) and P-15 bioactive peptide (iFactor, Cerapedics). Bioactive glass (S53P4 BAG, Bonalive) is added when infection is suspected. This study aims to objectify the effect of this treatment algorithm on the health-related quality of life (HRQoL) of patients with post-traumatic long bone non-unions. We hypothesized that HRQoL would improve after treatment.From January 2020 to March 2023, consecutive patients who were referred to a multidisciplinary (trauma, orthopaedic and plastic surgery) non-union clinic at the MUMC+, The Netherlands, were evaluated using the Non-Union Scoring System (NUSS). The EQ-5D-5L questionnaire and the Lower Extremity Functional Scale (LEFS) were employed to obtain HRQoL outcomes both prior to and subsequent to surgery, with a follow-up at 6, 18 and 35 weeks.Seventy-six patients were assessed at baseline (T0), with a mean NUSS of 40 (± 13 SD). Thirty-eight patients had their first follow-up, six weeks after surgery (T1). Thirty-one patients had a second follow-up at 18 weeks (T2), and twenty patients had the third follow-up at 35 weeks (T3). The EQ-5D index mean at baseline was 0.480, followed by an index of 0.618 at T1, 0.636 at T2, and 0.702 at T3. A significant difference was found in the HRQoL score between T0 and T1, as well as T2 and T3 (p&lt;0.001; p=0.011). The mean LEFS significantly increased from 26 before intervention to 34, 39, and 43 after treatment (p&lt;0.001; p=0.033; p=0.016).This study demonstrated a significant improvement in the health-related quality of life of patients with post-traumatic long bone non-unions after the standardized treatment algorithm following the induced membrane technique.