Introduction. The 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 & Methods. A 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). Results. A 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. Conclusions. This 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

The Masquelet or induced membrane technique (IMT) is a two-stage surgical procedure used for the treatment of segmental bone defects. In this technique, the defect is first filled with a polymethyl methacrylate (PMMA) spacer, which triggers the formation of a membrane that will encapsulate the defect. During the second surgery, the spacer is carefully removed and replaced by autologous bone graft while preserving the membrane. This membrane is vascularized, contains growth factors, and provides mechanical stability to the graft, all of which are assumed to prevent graft resorption and promote bone healing. The technique is gaining in popularity and several variations have been introduced in the clinical practice. For instance, orthopaedic surgeons now often include antibiotics in the spacer to treat or prevent infection. However, the consequences of this approach on the properties of the induce membrane are not fully understood. Accordingly, in a small animal model, this study aimed to determine the impact on the induced membrane of impregnating spacers with antibiotics frequently used in the IMT. We surgically created a five-mm segmental defect in the right femur of 25 adult male Sprague Dawley rats. The bone was stabilized with a plate and screws before filling the defect with a PMMA spacer. Animals were divided into five equal groups according to the type and dose of antibiotics impregnated in the spacer: A) no antibiotic (control), B) low-dose tobramycin (1.2 g/40 g of PMMA), C) low-dose vancomycin (1 g/40 g of PMMA), D) high-dose tobramycin (3.6 g/40 g of PMMA), E) high-dose vancomycin (3 g/40 g of PMMA). The animals were euthanized three weeks after surgery and the induced membranes were collected and divided for analysis. We assessed the expression of selected genes (Alpl, Ctgf, Runx2, Tgfb1, Vegfa) within the membrane by quantitative real-time PCR. Moreover, frozen sections of the specimens were used to quantify vascularity by immunohistochemistry (CD31 antigen), proliferative cells by immunofluorescence (Ki-67 antigen), and membrane thickness. Microscopic images of the entire tissue sections were taken and analyzed using FIJI software. Finally, we measured the concentration of vascular endothelial growth factor (VEGF) in the membranes by ELISA. No significant difference was found among the groups regarding the expression of genes related to osteogenesis (Alpl, Runx2), angiogenesis (Vegfa), or synthesis of extracellular matrix (Ctgf, Tgfb1) (n = four or five). Similarly, the density of proliferative cells and blood vessels within the membrane, as well as the membrane thickness, did not vary substantially between the control, low-dose, or high-dose antibiotic groups (n = four or five). The concentration of VEGF was also not significantly influenced by the treatment received (n = four or five). The addition of tobramycin or vancomycin to the spacer, at the defined low and high doses, does not significantly alter the bioactive characteristics of the membrane. These results suggest that orthopaedic surgeons could use antibiotic-impregnated spacers for the IMT without compromising the induced membrane and potentially bone healing

Introduction:. 20 cases of bone defect have been treated by the induced membrane technique avoiding allograft, microsurgery and amputation. Material and Methods:. 9 cases of long bone defect (humerus and forearm) and 11 cases of bone defect at the hand have been included in this multicentre prospective study (3 centers). The aetiology in 11 cases was trauma, 7 cases were septic nonunions and 2 cases followed tumors. In the hand the bone loss was at least one phalanx, and for long bones the mean defect was 5 cm (3–11). All cases were treated by the induced membrane technique which consists in stable fixation, flap if necessary and in filling the void created by the bone defect by a cement spacer (PMMA). This technique needs a second stage procedure at the 2. nd. month where the cement is removed and the void is filled by cancellous bone. The key point of this induced membrane technique is to respect the foreign body membrane which appeared around the cement spacer and which creates a biologic chamber for the second procedure. Bone union was evaluated prospectively in each case by a surgeon not involved in the treatment, by X-ray and CT scan. Failure was defined as a nonunion at 1 year, or an uncontrolled sepsis at 1 month. Results:. 3 cases failed to achieve bone union, 2 in the hand and 1 in a long bone. No septic complications occurred and all septic cases healed. In 14 cases bone union was achieved with a delay of 5 months (1, 5–12). 2 biopsies allowed us to prove that osteoid tissue was created by the technique. At hand level all fingers have included. At shoulder and elbow level, function reached 75% of motion of the contralateral side. Discussion:. Masquelet first reported 35 cases of large bone defect of tibia nonunion treated by the induced membrane technique which allow filling a bone defect with cancellous bone alone. The cement spacer induces a foreign body membrane (neo periosteum) which constitute a biological chamber. Animal models showed the properties of the membrane: secretion of growths factors (VEGF, TGFbéta1, BMP2) and osteoinductive activitie of the cells. Conclusion:. This technique is useful in emergency or in septic condition where a bone defect cannot be solved by shortening. The technique avoids the use of microsurgery and the limit is the quantity of available cancellous bone

Aim. The aim of this systematic review was to determine the reported treatment strategies, their individual success rates, and other outcome parameters in the management of critical-sized bone defects in Fracture-Related Infection (FRI) patients between 1990 and 2018. Method. We performed a systematic literature search on treatment and outcome of critical-sized bone defects in FRI. Treatment strategies identified were, autologous cancellous grafts, autologous cancellous grafts combined with local antibiotics, the induced membrane technique, vascularized grafts, bone transport, and bone transport combined with local antibiotics. Studies describing bone defects of 1 cm or greater were included. Outcomes were bone healing and infection eradication after primary surgical protocol and recurrence of FRI and amputations at the end of study period. Results. Fifty studies were included, describing 1,530 patients, of which the tibia was affected in 82%. The mean age was 40 years (range 6–80), with predominantly male subjects (79%). Mean duration of infection was 17 months (range 1–624) and mean follow-up lasted 51 months (range 6–126). Four studies (8%) described treatment using vascularized grafts, 18 (36%) cancellous grafts, 8 (16%) the induced membrane technique, and 20 (40%) bone transport. A total of 1063 grafts were used of which 30% were vascularized and 60% were cancellous bone. After initial protocolized treatment, FRI was cured in 83% (95% CI 79–87) of all cases, increasing to 94% (95% CI 92–96) at the end of each individual study. Recurrence of infection was seen in 8% (95% CI 6–11) and amputation in 3% (95% CI 2–3). Conclusions. This is the first extensive review of bone defect treatment protocols in chronic/late-onset FRI. Overall published work showed a high success rate of 94% and low amputation rate of only 3%. However, data did not allow a reliable comparison across treatments. The results should thus be interpreted with caution due to the retrospective and observational design of most studies, the lack of clear classification systems, incomplete data reports, potential underreporting of adverse outcomes, and heterogeneity in patient series. A consensus on classification, treatment protocols, and outcome is needed in order to improve reliability of future studies

Introduction. 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. Materials and Methods. 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. 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. Conclusions. 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

Background:. Wide resection of infected bone increases the chances of eradication of infection in patients with chronic osteomyelitis. Aggressive debridement is, however, frequently complicated by the creation of large bone defects. The use of antibiotic-impregnated PMMA spacers, as a customized dead space management tool, has recently grown in popularity. In addition to certain biological advantages, the spacer also offers a therapeutic benefit by serving as a vehicle for delivery of local adjuvant antibiotics. Methods:. This retrospective case series involved 11 patients with chronic osteomyelitis, managed with tibial bone transport through an induced membrane using circular external fixation. All patients were treated according to a standardized treatment protocol and we review the anatomic nature of the disease, the physiological status of the host, the surgical procedures performed, as well as the outcome of treatment in terms of eradication of infection, time to union and the complications that occurred. Results:. Nine patients, with a mean bone defect of 6 cm (range: 2–8 cm) were included in the study. At a mean follow-up of 24 months (range: 14–45 months) eradication of osteomyelitis was achieved in all patients without the need for reoperation for infection. Failure of the skeletal reconstruction occurred in two patients. Six major and four minor complications were experienced. After a mean time of 70 weeks (range: 30 to 104 weeks) in the circular external fixator all but one docking site had united and all regenerated segments were consolidated. Conclusion:. Bone transport, using circular external fixation, through the induced membrane created by the temporary insertion of a PMMA appears to be a useful technique in the management of post-infective tibial bone defects larger than 4 cm in size. Patient selection appears to be a crucial step in ensuring a successful outcome in terms of the resolution of infection

Methicillin– resistant Staphylococcus aureus (MRSA) infected gap non –union of long bones fractures is a challenge to manage. Treatment options are limited such a Ilizarov bone transport, vascularized bone free transfer etc. These techniques have complications and require expertise. We present a rare case with MRSA infected nonunion and bone defect 5cm of ulna which was managed with the induced membrane formation. A 33-years old male presented to outpatient department, 2 months after internal fixation on both left bone forearm fractures (Gustillo I). There was pus discharge from the operative site of ulna. Culture results: MRSA, C-Reactive Protein (CRP): 2,58 (0–5), Erythrocyte Sedimentation Rate (ESR): 42 (0–20). Intravenous (iv) Teicoplanin and Rifampicin were administrated and after one month no topic symptoms and CRP- ESR were normal. One month later he had again actively draining sinus (CRP: 1,47 ESR:22). The implant (ulna) was removed and a gap 5 cm was created at the fracture site (necrotic-infected bone debrided), which was filled by cemented spacer (Tobramycin and vancomycin). An external fixator was applied to ulna. Radius was not involved. Post op. iv the same antibiotics for 4 weeks. At the end of 8 weeks, the spacer was removed and the gap was filled with autologous cancellous bone graft (iliac crest). After 5 months the patient was reviewed. No any clinical and functional problems. Radiographics and CT-images were showed osseous consolidation. This technique (called as ‘Masquelet’) gives promising result in the management of infected long bone defects in upper extremity

Aim. The induced membrane technique (IMT) or Masquelet technique is a two-step surgical procedure used to treat bony defects (traumatic or resulting from tumoral resections) and pseudo arthroses, even caused by infections. The relatively small case series reported, sometimes with variants to the original technique, make it difficult to assess the real value of the technique. Aim of this study was then to undertake a systematic review of the literature with a particular focus on bone union, infection eradication and complication rates. Method. A systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Individual Patient Data (PRISMA-IPD) guidelines. PubMed and other medical databases were searched using “Masquelet technique” and “induced membrane technique” keywords. English, French or Italian written articles were included if dealing with IMT employed to long bones in adults and reporting at least 5 cases with a 12 months minimum follow-up. Clinical and bone defect features, aetiology, surgical data, complications, re-interventions, union and infection eradication rates were recorded into a database. Fischer's exact test and unpaired t-test were used for the statistical analysis on the individual patient's data. Results. Ten papers met the inclusion criteria (312 patients), but only 5 reported individual patients data (65 cases). IMT was used for acute bone loss (53%), septic (47%) and aseptic (7%) pseudo arthroses and tumour resections (2%). Bone defect length ranged from 0.6 to 26 cm. Overall, union rate was achieved in 88% of the cases and infection cured in 93%. Complication rate was 53%. Surgical variants included the use of antibiotic-loaded spacers (59.9%), internal fixation during the first step (62.1%), use of Reamer-Irrigator-Aspirator technique (40.1%) instead of iliac crest (63.1%) grafting, bone substitutes (18.3%) and growth factors addition (41%). No statistical differences were found comparing patient-related factors or surgical variants in achieving the two outcomes. Conclusions. IMT is effective to achieve bone union and infection eradication, but is associated with a high rate of complications and re-interventions. This should be taken into consideration by the surgeons and be a part of the informed consent. This systematic review was limited by the few studies meeting the inclusion criteria and their high variability in data reporting, making a meta-analysis impossible to undertake. Further studies are needed to demonstrate the role the patients’ clinical features and IMT variants with respect to bone union and infection eradication

A high volume of trauma and limited resources means that traditional methods of bone reconstruction are not feasible in parts of Africa. We present the management and outcomes of using Masquelet's concept, of an induced membrane and secondary morcellised cancellous bone grafting, in patients with severe lower limb trauma. Eleven patients were treated in an orthopaedic department in rural southern Africa between 2011 and 2012. This is a subgroup that is part of a larger study of open fractures that received ethical approval. All patients were male, with ten aged between 20 and 35 and one aged 70. Two were HIV positive. There were three open femur and eight open tibia fractures. Three required fasciocutaneous flaps and one required a muscle flap to achieve adequate soft tissue coverage. Eight cases were performed as the primary treatment and three were to treat septic non-unions. Bone defects ranged from 4 to 10 cm. Definitive bony stabilisation was maintained by mono-lateral external fixator in three patients. In other cases this was converted to a circular frame or internal fixation. The results have been mixed. In three patients bone grafting was delayed due to wound or pin site problems. In one case the bone graft was lost due to infection but repeating the procedure produced a good result. Time to bony union in each case is difficult to quantify. However, there is clear evidence of new bone forming in most cases. Four patients are weight bearing with external fixation removed, as are five patients with internal fixation. In a few cases bony union appears to be taking significantly longer, if at all. Masquelet technique is a welcome addition to the options available in bone reconstruction. However, time to achieve bony union is unpredictable. Refinement of the technique for use in the developing world is needed