Treatment options for infected bone defects in the lower extremities: free vascularized fibular graft or Ilizarov bone transport?

Functional Lower Limb Salvage

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Explain the basic concept of functional limb salvage. 2. Understand the complexity of salvaging the limb when consulting the patient, especially regarding how to obtain the best possible functional outcome, whether it be from limb salvage or amputation. 3. Implement orthoplastic thinking to salvage the limb. 4. Understand the latest innovations for limb salvage.

SUMMARY

The goal of limb salvage is to have the patient achieve the best possible function that allows daily activities (eg, walking and running) and the ability to perform tasks that require strength and dexterity. This is a complex process requiring the work of a multidisciplinary team practicing the principles of good wound care, orthoplastic thinking, and strategizing on future function. Understanding the new advances in this field of rapid change and growth will help reconstructive surgeons to make better decisions and incorporate them into daily practice, allowing for the best possible outcome.

Evaluation of the comparative efficacy and safety of surgical strategies for long bone defects: a network meta-analysis

BACKGROUND

To evaluate the safety and efficacy of various surgical treatments for long bone defects. Despite numerous observational studies, randomized controlled trials (RCTs), and meta-analyses, the optimal surgical treatment for long bone defects remains undetermined.

METHODS

A network meta-analysis (NMA) was conducted. PubMed, Embase, and the Cochrane Library were searched for articles published between 1 January 2000 and 12 January 2023 on surgical treatments for long bone defects. RCTs and observational studies comparing five surgical treatments were selected: the Masquelet technique (MT), bone transport (BT), vascularized bone graft (VBG), non-VBG (NVBG), and bone tissue engineering (BTE). Data were extracted by two independent reviewers. The NMA aggregated direct and indirect evidence. Treatments were ranked using the surface under the cumulative ranking curve (SUCRA) scores. Data are presented as mean differences and 95% confidence intervals. The primary outcomes were the postoperative healing rate, with subgroup analysis based on defect size (4-8 cm and >8 cm). The secondary outcomes included postoperative complications.

RESULTS

This NMA included 23 studies (three RCTs and 20 observational studies) with 930 participants (median age, 35 years). There were no significant differences in clinical outcomes among the treatments. VBG (SUCRA, 75.1%) was rated as optimal for healing, and BTE (SUCRA, 28.5%) was the least effective. BTE had the highest complication rate (SUCRA, 90.9%), whereas NVBG had the lowest complication rate (SUCRA, 27.6%). Subgroup analysis showed reduced heterogeneity: for 4-8 cm defects, VBG (SUCRA, 80.4%) was optimal, and for >8 cm defects, BT (SUCRA, 76.2%) was optimal.

CONCLUSIONS

VBG and BT may offer superior clinical outcomes for long bone defects compared to MT, NVBG, and BTE. However, BTE is associated with a high risk of complications. Further high-quality, large-sample RCTs are required to confirm these findings.

Cable-asisted bone transport versus circular external fixators-asisted bone transport in the management of bone defects of the Tibia: clinical and imaging results

PURPOSE

The aim of this study was to compare the efficacy, clinical outcomes, and complications of cable-asisted bone transport (CASt) and circular external fixator-assisted bone transport (CEFt) methods in the management of bone defects of the tibia.

METHODS

A retrospective analysis was conducted on 32 patients who underwent segmental bone transport for tibial bone defects between January 2006 and January 2020 and met the study inclusion criteria. Patients were categorized into two groups: CASt group (n = 16) and CEFt group (n = 16). The primary outcome measures included radiological parameters (External Fixator Index (EFI), Radiological Consolidation Time (RCT), and Radiological Consolidation Index (RCI)), functional independence (Lower Extremity Functional Index, LEFI) and functional outcomes (ASAMI Bone and Functional Scores). Secondary outcomes included pain levels (Visual Analog Scale, VAS), and complication rates (Paley's and Checketts-Otterburn classifications).

RESULTS

The CASt method resulted in significantly reduced pain scores during distraction (VAS: 4.81 ± 0.98 vs. 6.75 ± 0.86; p = 0.001). Pin-tract infection rates were significantly lower in the CASt group compared to the CEFt group (50% vs. 93.8%; p = 0.013). There was no significant difference between the groups in radiological (EFI, RCT, RCI) and functional outcomes (ASAMI scores) (p > 0.05).

CONCLUSION

Both CASt and CEFt methods are effective and reliable options in the management of bone defects of the tibia. However, CASt offers advantages such as lower pin-tract infection rates and less pain during distraction, resulting in greater patient comfort and compliance. Given its less invasive nature, CASt may be preferable in patients at higher risk of infection or with a low pain threshold. However, the technical complexity of this method requires experienced surgical application.

Ilizarov External Fixator Versus Orthofix LRS in Management of Femoral Osteomyelitis: A Propensity Score Matched Analysis

Purpose

Treatment of osteomyelitis (OM) is challenging. Ilizarov bone transport is a commonly used technique for management of OM. The recently introduced limb reconstruction system (LRS) has been effectively used for management of OM. It was suggested to be easier in use and less invasive. The present retrospective study aimed to compare LRS and Ilizarov bone transport in management of femoral OM using a propensity score matched analysis.

Methods

The present retrospective study included 80 consecutive patients with femoral OM. The studied patients were managed either using Ilizarov external fixator (n = 40) or Orthofix LRS (n = 40). The clinical outcome measurements included union time, limb length discrepancy, additional operative procedures, refracture and infection.

Results

Patients in the LRS group were exposed to significantly higher frequency of bone transport (30.0 versus 15.0%) and lower frequency of acute compression and lengthening (10.0 versus 32.5%). Patients in Ilizarov group had significantly higher frequency of tobramycin pellets as compared to their counterparts. The studied groups were comparable regarding the operative complications including pin-tract infection, non-union at docking site and refracture. Patients in the Ilizarov had significantly shorter time to union (8.2 ± 3.2 versus 11.0 ± 5.6 months, p = 0.012). No statistically significant differences were found between the studied groups regarding the quality-of-life domains.

Conclusions

Use of Ilizarov external fixator and Orthofix LRS devices proved to be effective and reliable. Their influences on patients' quality appear to be comparable.

Youthful small extracellular vesicles restore the function and reparative capacity of inflammatory-impaired periodontal ligament stem cells via delivering protein biglycan for bone regeneration

Regenerating inflamed bone defects represents a severe clinical challenge due to the undesirable inflammatory microenvironment. The inflammatory stimulus poses a weighty threat to the regenerative capacity of endogenously derived mesenchymal stem cells (MSCs), which are mainly responsible for osteogenic differentiation, thereby resulting in compromised endogenous bone formation. Consequently, alleviating the biological characteristics of inflammatory-impaired MSCs is crucial for promoting inflamed bone regeneration. Nano-sized small extracellular vesicles (sEVs) have emerged as promising therapeutic tools to orchestrate MSCs fate due to their intrinsic biocompatibility and encapsulated bioactive contents. In the present study, we extracted sEVs from youthful and adult dental pulp MSCs and explored their ability to recover inflammation-compromised periodontal ligament stem cells (IPDLSCs). The results indicated that both types of sEVs were capable of facilitating IPDLSCs osteogenesis. However, young sEVs exhibited a more robust potential at a lower concentration compared to adult sEVs. Mechanically, young sEVs enhanced the expression of bone morphogenetic protein 4 (BMP4) via delivering the protein Biglycan, which correspondingly promoted the osteogenic capability of IPDLSCs. Collectively, our findings emphasized that young sEVs hold enormous potential to rescue the inherent function and regenerative competence of inflammation-impaired MSCs, shedding light on their promising therapeutic prospects for infected bone regeneration.

Tibial bone loss

Critical bone loss after open fractures, while relatively uncommon, occurs most frequently in high-energy injuries. Fractures of the tibia account for the majority of open fractures with significant bone loss. A number of different surgical strategies exist for treatment of tibial bone loss, all with different advantages and disadvantages. Care should be taken by the surgeon to review appropriate indications and all relevant evidence before selecting a strategy.

Can locking plate fixation and free Vascularised fibular transfer with skin island achieve good functional outcome in the treatment of large bone defects of Tibia ? A study of 26 cases

BACKGROUND

Despite the availability of multiple treatment options, management of tibial bone loss continues to be a challenge. Free vascularized fibula graft (FVFG) with a skin paddle offers better advantages over the other methods. We aimed to study the functional outcomes and QALY of patients with large tibial bone defects following FVFG with a locking plate.

MATERIALS AND METHODS

We analyzed 26 consecutive patients with large tibial bone defects treated by free vascularized fibular graft (FVFG) and stabilization using a long locking plate between 2009 and 2018. All were followed up for a mean period of 42 months (24 to 120 months). Bony union, graft hypertrophy, and complications such as stress fracture and infections were assessed. Multivariate regression analysis was performed to identify any association between demographic factors, injury characteristics, treatment-related factors, and fibular hypertrophy. Additionally, The EQ-5D quality-of-life (QOL) indices were obtained using the SF-12 score to evaluate the patients' overall quality of life.

RESULTS

The mean age of the patients at the time of presentation was 36.26 yrs (range, 18-60 years). The cause of bone loss was open injury in 16 patients and infected nonunion in 10 patients. Complete union was achieved in 25 patients (96 %) without any requirement of additional surgical procedures. The mean union time of the graft was 4.04 months (range, 3-6 months). The mean fibular hypertrophy calculated by De Boer index was 0.61 %, 11 %, 28.24 % and 52.52 % at 3,6 months and 1 and 2 years respectively. Patients with metaphyseal bone loss have significant fibular hypertrophy. Participants in our study experienced a quality of life equivalent to 0.88 (range 0.79-0.99) of perfect health.

CONCLUSIONS

FVFG with skin paddle and LCP fixation for massive tibial bone loss achieved satisfactory outcome and QALY even in the challenging healthcare environment of South India, a developing country.It maintains alignment, promotes graft hypertrophy, and prevents stress fractures.

LEVEL OF EVIDENCE

Level 4 LEVEL OF CLINICAL CARE: Level I Tertiary trauma centre.

Trifocal versus Pentafocal bone transport in segmental tibial defects: a matched comparative analysis for posttraumatic osteomyelitis treatment

PURPOSE

The objective of this study was to evaluate and compare the effectiveness and clinical results of trifocal bone transport (TBT) and pentafocal bone transport (PBT) in treating distal tibial defects > 6 cm resulting from posttraumatic osteomyelitis, highlighting the potential advantages and challenges of each method.

METHODS

A retrospective assessment was conducted on an overall population of 46 eligible patients with distal tibial defects > 6 cm who received treatment between January 2015 and January 2019. Propensity score analysis was used to pair 10 patients who received TBT with 10 patients who received PBT. The outcomes assessed included demographic information, external fixation time (EFT), external fixation index (EFI), bone and functional outcomes assessed using the Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system, and postoperative complications evaluated using the Paley classification.

RESULTS

The demographic and baseline data of the two groups were comparable. Following radical debridement, the average tibial defect was 7.02 ± 0.68 cm. The mean EFT was significantly shorter in the PBT group (130.9 ± 16.0 days) compared to the TBT group (297.3 ± 14.3 days). Similarly, the EFI was lower in the PBT group (20.67 ± 2.75 days/cm) than in the TBT group (35.86 ± 3.69 days/cm). Both groups exhibited satisfactory postoperative bone and functional results. Pin site infection was the most common complication and the rates were significantly different between the groups, with the PBT group demonstrating a higher incidence.

CONCLUSION

Both TBT and PBT effectively treat posttraumatic tibial defects greater than 6 cm, with PBT offering more efficient bone regeneration. However, PBT is associated with a higher rate of pin site infections, highlighting the importance of careful management in these complex procedures and emphasizing the need for expert surgical execution and tailored treatment approaches in orthopedic reconstructive surgery.

Free iliac crest grafting technology for the management of critical-sized tibial bone defect

OBJECTIVE

To introduce the method and experience of treating critical-sized tibial bone defect by taking large iliac crest bone graft.

METHODS

From January 2020 to January 2022, iliac crest bone grafting was performed in 20 patients (10 men and 10 women) with critical-sized tibial bone defect. The mean length of bone defect was 13.59 ± 3.41. Bilateral iliac crest grafts were harvested, including the inner and outer plates of the iliac crest and iliac spine. The cortical bone screw was used to integrate two iliac bone blocks into one complex. Locking plate was used to fix the graft-host complex, supplemented with reconstruction plate to increase stability when necessary. Bone healing was evaluated by cortical bone fusion on radiographs at follow-up, iliac pain was assessed by VAS score, and lower limb function was assessed by ODI score. Complications were also taken into consideration.

RESULTS

The average follow-up time was 27.4 ± 5.6 (Range 24-33 months), the mean VAS score was 8.8 ± 1.9, the mean ODI score was 11.1 ± 1.8, and the number of cortical bone fusion in the bone graft area was 3.5 ± 0.5. Satisfactory fusion was obtained in all cases of iliac bone transplant-host site. No nonunion, shift or fracture was found in all cases. No infection and bone resorption were observed that need secondary surgery. One patient had dorsiflexion weakness of the great toe. Hypoesthesia of the dorsal foot was observed in 2 patients. Ankle stiffness and edema occurred in 3 patients. Complications were significantly improved by physical therapy and rehabilitation training.

CONCLUSION

For the cases of critical-sized tibial bone defect, the treatment methods are various. In this paper, we have obtained satisfactory results by using large iliac bone graft to treat bone defect. This approach can not only restore the integrity of the tibia, but also obtain good stability with internal fixation, and operation skills are more acceptable for surgeons. Therefore, it provides an alternative surgical method for clinicians.

Advances in the Application of Bone Transport Techniques in the Treatment of Bone Nonunion and Bone Defects

Bone nonunion and bone defects frequently occur following high-energy open injuries or debridement surgeries, presenting complex challenges to treatment and significantly affecting patients' quality of life. At present, there are three primary treatment options available for addressing bone nonunion and bone defects: vascularized bone grafts, the Masquelet technique, and the Ilizarov technique. The Ilizarov technique, also known as distraction osteogenesis, is widely favored by orthopedic surgeons because of several advantages, including minimal soft tissue requirements, low infection risk, and short consolidation time. However, in recent years, the application of the Masquelet technique has resulted in novel treatment methods for managing post-traumatic bone infections when bone defects are present. Although these new techniques do not constitute a panacea, they continue to be the most commonly employed options for treating complex large bone nonunion and bone defects. This review evaluates the currently available research on the Ilizarov and Masquelet bone transport techniques applied at various anatomical sites. Additionally, it explores treatment durations and associated complications to establish a theoretical foundation that can guide clinical treatment decisions and surgical procedures for the management of bone nonunion and bone defects.

Self-promoted electroactive biomimetic mineralized scaffolds for bacteria-infected bone regeneration

Infected bone defects are a major challenge in orthopedic treatment. Native bone tissue possesses an endogenous electroactive interface that induces stem cell differentiation and inhibits bacterial adhesion and activity. However, traditional bone substitutes have difficulty in reconstructing the electrical environment of bone. In this study, we develop a self-promoted electroactive mineralized scaffold (sp-EMS) that generates weak currents via spontaneous electrochemical reactions to activate voltage-gated Ca2+ channels, enhance adenosine triphosphate-induced actin remodeling, and ultimately achieve osteogenic differentiation of mesenchymal stem cells by activating the BMP2/Smad5 pathway. Furthermore, we show that the electroactive interface provided by the sp-EMS inhibits bacterial adhesion and activity via electrochemical products and concomitantly generated reactive oxygen species. We find that the osteogenic and antibacterial dual functions of the sp-EMS depend on its self-promoting electrical stimulation. We demonstrate that in vivo, the sp-EMS achieves complete or nearly complete in situ infected bone healing, from a rat calvarial defect model with single bacterial infection, to a rabbit open alveolar bone defect model and a beagle dog vertical bone defect model with the complex oral bacterial microenvironment. This translational study demonstrates that the electroactive bone graft presents a promising therapeutic platform for complex defect repair.

Debridement-Reconstruction-Docking Management System Versus Ilizarov Technique for Lower-Extremity Osteomyelitis

BACKGROUND

Osteomyelitis causes marked disability and is one of the most challenging diseases for orthopaedists to treat because of the considerable rate of infection recurrence. In this study, we proposed and assessed the debridement-reconstruction-docking (DRD) system for the treatment of lower-extremity osteomyelitis. This procedure comprises 3 surgical stages and 2 preoperative assessments; namely, pre-debridement assessment, debridement, pre-reconstruction assessment, reconstruction, and docking-site management. We evaluated the use of the DRD system compared with the Ilizarov technique, which is defined as a 1-stage debridement, osteotomy, and bone transport.

METHODS

This retrospective cohort included 289 patients who underwent either DRD or the Ilizarov technique for the treatment of lower-extremity osteomyelitis at a single institution between January 2013 and February 2021 and who met the eligibility criteria. The primary outcome was the rate of infection recurrence. Secondary outcomes included the external fixator index (EFI), refracture rate, and the Paley classification for osseous and functional results. An inverse-probability-weighted regression adjustment model was utilized to estimate the effect of the DRD system and Ilizarov technique on the treatment of lower-extremity osteomyelitis.

RESULTS

A total of 131 and 158 patients underwent DRD or the Ilizarov technique, respectively. The inverse-probability-weighted regression adjustment model suggested that DRD was associated with a significant reduction in infection recurrence (risk ratio [RR], 0.26; 95% confidence interval [CI], 0.13 to 0.50; p < 0.001) and EFI (-6.9 days/cm, 95% CI; -8.3 to -5.5; p < 0.001). Patients in the DRD group had better Paley functional results than those in the Ilizarov group (ridit score, 0.55 versus 0.45; p < 0.001). There was no significant difference between the 2 groups in the rate of refracture (RR, 0.87; 95% CI, 0.42 to 1.79; p = 0.71) and Paley osseous results (ridit score, 0.51 versus 0.49; p = 0.39).

CONCLUSIONS

In this balanced retrospective cohort of patients with lower-extremity osteomyelitis, the use of the DRD system was associated with a reduced rate of infection recurrence, a lower EFI, and better Paley functional results compared with the use of the Ilizarov technique.

LEVEL OF EVIDENCE

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

Characterization of the Masquelet Induced Membrane Technique in a Murine Segmental Bone Defect Model

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.

A modified induced membrane 2-stage technique using a thoracodorsal artery perforator free flap followed by vascularized or non-vascularized free fibular transfer for the treatment of complex bone infection with concomitant severe soft tissue lesion-A case series of 9 cases

Treatment of post-traumatic complex bone infection is very challenging. The two principal bone reconstruction approaches are the single-stage vascularized bone graft technique and the two-stage induced membrane technique (IMT). Here we introduce a modified 2-stage induced membrane technique (MIMT) for complex long bone infection with a major bone defect and a concomitant severe soft tissue lesion. The 2-stage procedure consists of bone debridement, placement of a PMMA spacer and soft tissue reconstruction with a thoracodorsal artery perforator free flap ("Tdap") at stage 1. At stage 2, the thoracodorsal artery perforator flap is elevated and a fibular strut graft (either vascularized of non-vascularized) is placed for bone reconstruction. We retrospectively analyzed the extents of lower extremity, long bone, post-traumatic bone infection treated via MIMT from 2008 to 2020. There were nine such cases (eight males) of mean age 59.8 (range 31 to 79) years. The osteomyelitis durations ranged from 3 to 360 months (mean 53 months). The cortical bone defect sizes was ranged from 9 to 14 cm (mean10.7 cm). All skin resurfacing employed Tdap. Vascularized fibular grafts were placed in six patients and non-vascularized grafts were placed in three. The fibular graft size ranged from 12.5 to 19 cm (mean 16.2 cm). Non-vascularized iliac bone grafts served as the fibula docking sites. Unfortunately, all patients suffered complications before bone union was achieved. One case of plate stress fracture and one case of screw fracture required plate and screw change. In three cases of cellulitis, one resolved by use of intravenous antibiotics, others required plate and screw removal. Wound disruption required re-suture and distal skin flap partial necrosis was covered by perforator-based island flap. One case of fibular stress fracture needed cast for 4 weeks. A peroneal nerve palsy patient recovered spontaneously. Bone union was achieved after 6 months in five patients and after 8 months in three (mean 6.9 months). All patients were able to walk unaided. The follow-up period ranged from 2 to 14 years (mean 6.2 years). MIMT saves the limbs in cases with difficult post-traumatic bone infection. It is valid treatment option for complex bone infections with severe soft tissue lesions. However, even with this technique potential complication must be considered.

Reconstruction of a Severe Open Tibiofibular Fracture using an Ipsilateral Vascularized Fractured Fibula with a Thoracodorsal Artery Perforator Free Flap

The Gustilo IIIB tibiofibular fractures often result in long bone loss and extensive soft tissue defects. Reconstruction of these complex wounds is very challenging, especially when it includes long bone grafts, because the donor site is limited. We describe our experience using a set of chimeric ipsilateral vascularized fibula grafts with a thoracodorsal artery perforator free flap to reconstruct the traumatic tibia defects. A 66-year-old male suffered a severe comminuted tibia fracture and segmented fibula fracture with large soft tissue defects as a result of a traffic accident. He also had an open calcaneal fracture with soft tissue defects on the ipsilateral side. All the main vessels of the lower extremity were intact, and the cortical bone defect of the tibia was almost as large as the fractured fibula segment. We used an ipsilateral vascularized fibula graft to reconstruct the tibia and a thoracodorsal artery perforator flap to resurface the soft tissue, using the distal ends of peroneal vessels as named into sequential chimeric flaps. After 3 weeks, the calcaneal defect was reconstructed with second thoracodorsal artery perforator free flap. Reconstruction was successful and allowed rapid rehabilitation because of reduced donor site morbidity.

Proximal versus distal bone transport for the management of large segmental tibial defect: a clinical case series

This retrospective study compared proximal bone transport and distal bone transport in a series of cases diagnosed with large segmental tibial defects. Patients with a tibial segmental defect (> 5 cm) were eligible for inclusion. Twenty-nine patients were treated using proximal bone transport technique (PBT group) and 21 cases were managed by distal bone transport technique (DBT group). We recorded the demographic information, operation indexes, external fixation index (EFI), visual analog score (VAS), limb function scores, and complications. Patients were followed for 24-52 months. There was no significant difference in operation time, blood loss, time in frame, EFI and HSS score between the two groups (p > 0.05). However, the PBT group displayed better clinical effects than the DBT group, including higher AOFAS scores, lower VAS, and complication incidence (p < 0.05). In particular, the incidence of Grade-II pin-tract infection, transient loss of ankle movement, and foot drop was significantly lower in PBT group than that in DBT group (p < 0.05). Although both methods could be used safely for the management of large segmental tibial defects, the proximal bone transport may confer greater patient satisfaction because of better ankle functions and lower complications.

β-tricalcium phosphate/gelatin composite scaffolds incorporated with gentamycin-loaded chitosan microspheres for infected bone defect treatment

The repair of infected bone defects remains a clinical challenge. Staphylococcus aureus is a common pathogenic micro-organism associated with such infections. Gentamycin (GM) is a broad spectrum antibiotic that can kill S. aureus in a dose-dependent manner. However, the systemic administration of antibiotics may lead to drug resistance and gut dysbiosis. In this work, we constructed β-tricalcium phosphate/gelatin composite scaffolds incorporated with gentamycin-loaded chitosan microspheres (CMs(GM)-β-TCP/gelatin composite scaffolds), which helped optimize the local GM release in the infected defect areas and enhance bone regeneration. The cumulative release curves showed that both microspheres and composite scaffolds reached a sustained slow-release phase after the initial rapid release, and the latter further stabilized the initial drug release rate. The release curve of CMs(GM)-β-TCP/gelatin composite scaffolds reached a plateau after 24 h, and the cumulative release reached 41.86% during this period. Moreover, the combination of β-TCP and gelatin mimicked bone composition and were able to provide the requisite mechanical strength (0.82 ± 0.05 MPa) during the first phase of bone generation. The inner structure of the scaffold was arranged in the shape of interconnected pores, and presented a porosity level of 16%. The apertures were uniform in size, which was beneficial for cell proliferation and material transportation. Macroscopic observation and histological analysis showed that CMs(GM)-β-TCP/gelatin composite scaffolds fused with bone tissues, and new tissues were formed in defect areas without any infection. This new composite scaffold may be a promising repair material for treating infected bone defects.

Tetrafocal (three osteotomies) and pentafocal (four osteotomies) bone transport using Ilizarov technique in the treatment of distal tibial defect-preliminary outcomes of 12 cases and a description of the surgical technique

OBJECTIVE

To evaluate the preliminary outcomes of tetrafocal (three osteotomies) and pentafocal (four osteotomies) bone transport using Ilizarov technique for the treatment of distal tibial defect and describe the surgical technique.

METHODS

A total of 12 eligible patients with distal tibial defect > 6 cm caused by direct trauma or posttraumatic osteomyelitis who were admitted to our institution from January 2017 to January 2019 were treated by tetrafocal or pentafocal bone transport using Ilizarov technique. Detailed demographic data, including age, sex, etiology, defect size, number of osteotomies (three or four), external fixation time (EFT) and external fixation index (EFI), were collected, and the bone and functional outcomes were evaluated by the Association for the Study and Application of the Method of Ilizarov (ASAMI) scoring system. Complications during the surgery and the follow-up period were recorded and evaluated by the Paley classification at a minimum follow-up of two years after removal of the fixator.

RESULTS

There were 9 men and 3 women with an average age of 37.4±7.8 years. The etiology included posttraumatic osteomyelitis in 8 cases and posttraumatic bone loss in 4 cases. The mean bone defect after radical debridement was 7.1±0.6 cm. Tetrafocal bone transport was applied in 9 cases, and pentafocal bone transport was applied in 3 cases. The average EFT and EFI were 5.2±0.8 months and 0.7±0.2 months/cm, respectively. The average time of follow-up after removal of the external fixator was 28.5±3.3 months without recurrence of osteomyelitis. The bone results were good in 7 cases, fair in 4 cases, and poor in 1 case, and the functional results were good in 5 cases, fair in 6 cases, and poor in 1 case. The most common complication was pin tract infection, which occurred in all cases, but there were no major complications, such as nerve or vascular injury.

CONCLUSION

Tetrafocal and pentafocal bone transport using Ilizarov technique could be an alternative treatment option in selected cases with distal tibial defect > 6 cm. It could shorten the distraction period, fasten regeneration, and reduce the associated complications.

Evolution and Development of Ilizarov Technique in the Treatment of Infected Long Bone Nonunion with or without Bone Defects

The treatment of infected bone nonunion and bone defects is a considerable challenge in the orthopedics field. The standard clinical therapy methods include local free bone transplantation, vascularized bone graft, and the Ilizarov technique; the first two are controversial due to the iatrogenic self‐injury. The Ilizarov bone transport technique has been widely used to treat infected bone nonunion and bone defects, and good clinical effect has been demonstrated. Yet, it brings many related complications, which exerts additional suffering to the patient. The best treatment is to combine bone defect rehabilitation with infection control, intramedullary nail fixation, appropriate time for bone grafts, beaded type scaffold slippage and new Taylor fixation, reducing the external fixation time and the incidence of complications, thereby reducing the occurrence of patients' physical and psychological problems. This review focuses on the induction, summary and analysis of the Ilizarov bone transport technique in the treatment of infected long bone nonunion with or without bone defects, providing new ideas and methods for orthopedic disease prevention and treatment by the Ilizarov technique, which is following the development direction of digital orthopedics.

Progress in diagnosis and treatment of post-traumatic osteomyelitis

Post-traumatic osteomyelitis is one of the most common disorders of bone infection, which is secondary to open fracture caused by machinery injury, traffic accident, and it is also the main manifestation in the postoperative infection of open fracture. After trauma, bacteria invade bone tissue and reproduce rapidly in large quantities, which easily leads to osteomyelitis. Patients are often complaint of pain at the affected limb, loss of function, or even amputation due to deteriorated infection, resulting in loss of labor capability and poor quality of life. Because the diagnosis and treatment are not timely and standard, the treatment for post-traumatic osteomyelitis is often delayed, resulting in the difficulty of clinical cure. It also makes patients and their families bear a serious financial burden. However, the diagnosis and treatment for this disease is difficult for orthopedic physicians. In recent years, imaging methods (such as CT and MRI) combined with immune techniques have significantly improved the diagnostic accuracy and early diagnosis ability. The application of new diagnostic technologies (such as gene chip and second-generation sequencing) also makes the diagnosis more convenient and sensitive. The novel reconstruction and repair surgery (such as Ilizarov technology and Orthofix LRS technology) provides new treatment direction for orthopedic surgeons and patients.

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research (dedicated to 100th birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed "limb lengthening and reconstruction surgery". Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal's rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.