Fibula and tibia fusion with cancellous allograft vitalised with autologous bone marrow: first results for infected tibial non-union

Bone marrow aspirate and bone marrow aspirate concentrate: Does the literature support use in long-bone nonunion and provide new insights into mechanism of action?

PURPOSE

To assess the use of bone marrow aspirate (BM) and bone marrow aspirate concentrate (BMAC) in the treatment of long-bone nonunion and to understand mechanism of action.

METHODS

A systematic review of PubMed and EBSCOHost was completed to identify studies that investigated the use of BM or BMAC for the diagnosis of delayed union and/or nonunion of long-bone fractures. Studies of isolated bone marrow-mesenchymal stem cells (BM-MSCs) and use in non-long-bone fractures were excluded. Statistical analysis was confounded by heterogeneous fracture fixation methods, treatment history, and scaffold use.

RESULTS

Our initial search yielded 430 publications, which was screened down to 25 studies. Successful treatment in aseptic nonunion was reported at 79-100% (BM) and 50-100% (BMAC). Septic nonunion rates were slightly better at 73-100% (BM) and 83.3-100% (BMAC). 18/24 studies report union rates > 80%. One study reports successful treatment of septic nonunion with BMAC and no antibiotics. A separate study reported a significant reduction in autograft reinfection rate when combined with BMAC (P = 0.009). Major adverse events include two deep infections at injection site and one case of heterotopic ossification. Most studies note transient mild donor site discomfort and potential injection site discomfort attributed to needle size.

CONCLUSION

The current literature pertaining to use of BM/BMAC for nonunion is extremely heterogeneous in terms of patient population and concomitant treatment modalities. While results are promising for use of BM/BMAC with other gold standard treatment methodologies, the literature requires additional Level I data to clarify the impact of role BM/BMAC in treating nonunion when used alone and in combination with other modalities.

LEVEL OF EVIDENCE

Level III.

Ilizarov method and its combined methods in the treatment of long bone defects of the lower extremity: systematic review and meta-analysis

BACKGROUND

Ilizarov method has become one of primary methods for treating bone defects. Currently, there is growing trend in the application of modified Ilizarov methods (e.g., applying unilateral external fixators or with flap tissue) and its combined methods (e.g., Ilizarov method with antibiotic spacer or internal fixation) to manage bone defects. However, there is a lack of studies with systematical evaluation of the clinical effects of these evolving methods. This study aimed to conduct a systematic review and meta-analysis for overall evaluating the clinical effects on long bone defects of lower extremity in Ilizarov methods and its combined methods.

METHODS

Studies were identified in three electronic databases (Pubmed, Embase and Cochrane Library) from the earliest indexing year through November 01, 2022, and relevant data were extracted subsequently. The total number of participants, number of participants with bone unions, bone result or functional result, and related complications including pin infection, pin loosening, pain, refracture, limb discrepancy, malalignment, joint stiffness, recurrent infection, and amputation were extracted in this study. Then, union rate (defined as the proportion of patients who achieved bone unions) and specific complication incidence rate (defined as the proportion of patients who experienced specific complication) were pooled estimated respectively. Relative risk (RR) was used for comparing the clinical effects among various Ilizarov technique.

RESULTS

Sixty-eight case series studies, 29 comparative studies, and 3 randomized clinical trials were finally included. The union rate of Ilizarov methods was 99.29% (95% CI: 98.67% ~ 99.86%) in tibial defects and 98.81% (95% CI: 98.81% ~ 100.00%) in femoral defects. The union rate of Ilizarov method with antibiotic spacer and intramedullary nail in tibial defects was 99.58% (95% CI: 98.05% ~ 100.00%) and 95.02% (95% CI: 87.28% ~ 100.00%), respectively. Compared to the Ilizarov methods, the union rate of the Ilizarov method with antibiotic spacer in tibial defects increased slightly (RR = 1.02, 95% CI: 1.01 ~ 1.04). Meanwhile, compared to Ilizarov methods, we found lower excellent rate in bone result in Ilizarov method with antibiotic spacer, with the moderate to high heterogeneity. Compared to the Ilizarov method, lower rate of pin infection, higher rate of recurrent infection and amputation were observed in Ilizarov method with intramedullary nail, however, the findings about the comparison of pin infection and recurrent infection between the two groups were presented with high degree of statistical heterogeneity.

CONCLUSION

Our study confirmed the reliable treatment of Ilizarov methods and its combined technique on long bone defects, and founded there were significant differences on some complications rate between Ilizarov methods and its combined technique. However, the findings need to be confirmed by further studies.

Fibula pro tibia and cancellous allograft vitalised with autologous bone for non-union of the distal tibia diaphysis: Surgical technique

Background

The management of medium-sized osseous defects and pseudoarthrosis of the tibia is challenging. This surgical technique aims to bridge medium-sized tibial defects using the fibula as a lead structure. The fibula and cancellous bone graft fuse with the tibia leading to synostosis.

Methods

Cortico-cancellous bone is harvested from the anterior iliac crest. The bone is shredded into small pieces of about 5 mm and mixed with stem cell-rich blood from the situs. Additionally, cancellous allografts can be used for expansion. The approach is extended along the interosseous membrane to reach the tibial defect. The pseudarthrosis is debrided and the tibial bone adjacent to the defect is decorticated. A 3.5 mm 1/3 tube plate is positioned to the fibula and fixed. Four quadricortical screws are positioned. Autograft is secured into the tibial bone defect and between the fibula and the tibia directly on the anterior surface of the interosseous membrane.

Results

15 patients were followed up for a mean of 17 months. Osseous consolidation was achieved in 73.3% of all cases. On average, bone healing has occurred 17 weeks postoperatively. These patients did not have any pain walking with full weight bearing and without any walking aids at the last follow-up.

Conclusion

The fibula pro tibia procedure is a sufficient tool for treating non-unions of the mid and distal third of the tibia diaphysis in cases with a bony defect size of 1 cm-6 cm.

Treatment of Posttraumatic Tibial Diaphyseal Bone Defects: A Systematic Review and Meta-Analysis

OBJECTIVE

To describe evidenced-based treatment options for patients who sustained trauma and/or posttraumatic osteomyelitis of the tibia resulting in diaphyseal bone defects and to compare outcomes between patients treated with nonvascularized bone grafts (NBGs), bone transport (BT), or vascularized bone grafts (VBGs).

DATA SOURCE

The Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data and Cochrane guidelines were followed. PubMed, EMBASE, Cochrane Library, Web of Science, Scopus, and CINAHL were searched from inception to June 2020.

STUDY SELECTION

Patients who were ≥18 years, had sustained trauma to the tibia resulting in fracture and/or osteomyelitis with measurable diaphyseal bone defects, and were treated by interventions such as NBGs, BT, or VBGs were eligible. Excluded studies were non-English, reviews, nonreviewed literature, cadavers, animals, unavailable full texts, nondiaphyseal defects, atrophic nonunions, malignancy, and replantations.

DATA EXTRACTION

A total of 108 studies were included with 826 patients. Two reviewers systematically/independently screened titles/abstracts, followed by full texts to ensure quality, accuracy, and consensus among authors for inclusion/exclusion of studies. A third reviewer addressed disagreements if investigators were unable to reach a consensus. Studies were quality assessed using "Methodological Quality and Synthesis of Case Series and Case Reports".

DATA SYNTHESIS

Analyses were performed with IBM SPSS version 25.0 (IBM Corporation, Armonk, NY) and G*Power3.1.9.2.

CONCLUSIONS

NBGs may be considered first line for trauma defect sizes ≤ 10 cm or posttraumatic osteomyelitis defect sizes <5 cm. BT may be considered first line for posttraumatic osteomyelitis defect sizes <5 cm. VBGs may be considered first line for trauma and posttraumatic osteomyelitis defect sizes ≥5 cm.

LEVEL OF EVIDENCE

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

Bone Marrow-Derived Cell Therapies to Heal Long-Bone Nonunions: A Systematic Review and Meta-Analysis-Which Is the Best Available Treatment?

Nonunions represent one of the major indications for clinical settings with stem cell-based therapies. The objective of this research was to systematically assess the current evidence for the efficacy of bone marrow-derived cell-based approaches associated or not with bone scaffolds for the treatment of nonunions. We searched MEDLINE (PubMed) and CENTRAL up to July 2019 for clinical studies focused on the use of cell-based therapies and bone marrow derivatives to treat bone nonunions. Three investigators independently extracted the data and appraised the risk of bias. We analysed 27 studies including a total number of 347 participants exposed to four interventions: bone marrow concentrate (BMAC), BMAC combined with scaffold (BMAC/Scaffold), bone marrow-derived mesenchymal stromal cells (BMSCs), and BMSC combined with scaffold (BMSC/Scaffold). Two controlled studies showed a positive trend in bone healing in favour of BMAC/Scaffold or BMSC/Scaffold treatment against bone autograft, although the difference was not statistically significant (RR 0.11, 95% CI -0.05; 0.28). Among single cohort studies, the highest mean pooled proportion of healing rate was reported for BMAC (77%; 95% CI 63%-89%; 107 cases, n = 8) and BMAC/Scaffold treatments with (71%; 95% CI 50%-89%; 117 cases, n = 8) at 6 months of follow-up. At 12 months of follow-up, an increasing proportion of bone healing was observed in all the treatment groups, ranging from 81% to 100%. These results indicate that BMAC or BMAC/Scaffold might be considered as the primary choice to treat nonunions with a successful healing rate at a midterm follow-up. Moreover, this meta-analysis highlighted that the presence of a scaffold positively influences the healing rate at a long-term follow-up. More case-control studies are still needed to support the clinical improvement of cell-based therapies against autografts, up to now considered as the gold standard for the treatment of nonunions.

Novel Lipid Signaling Mediators for Mesenchymal Stem Cell Mobilization during Bone Repair

Introduction

Mesenchymal stem and progenitor cells (MSCs), which normally reside in the bone marrow, are critical to bone health and can be recruited to sites of traumatic bone injury, contributing to new bone formation. The ability to control the trafficking of MSCs provides therapeutic potential for improving traumatic bone healing and therapy for genetic bone diseases such as hypophosphatasia.

Methods

In this study, we explored the sphingosine-1-phosphate (S1P) signaling axis as a means to control the mobilization of MSCs into blood and possibly to recruit MSCs enhancing bone growth.

Results

Loss of S1P receptor 3 (S1PR3) leads to an increase in circulating CD45-/CD29+/CD90+/Sca1 putative mesenchymal progenitor cells, suggesting that blocking S1PR3 may stimulate MSCs to leave the bone marrow. Antagonism of S1PR3 with the small molecule VPC01091 stimulated acute migration of CD45-/CD29+/CD90+/Sca1+ MSCs into the blood as early as 1.5 hours after treatment. VPC01091 administration also increased ectopic bone formation induced by BMP-2 and significantly increased new bone formation in critically sized rat cranial defects, suggesting that mobilized MSCs may home to injuries to contribute to healing. We also explored the possibility of combining S1P manipulation of endogenous host cell occupancy with exogenous MSC transplantation for potential use in combination therapies. Importantly, reducing niche occupancy of host MSCs with VPC01091 does not impede engraftment of exogenous MSCs.

Conclusions

Our studies suggest that MSC mobilization through S1PR3 antagonism is a promising strategy for endogenous tissue engineering and improving MSC delivery to treat bone diseases.

Nonunion fractures, mesenchymal stem cells and bone tissue engineering

Depending on the duration of healing process, 5-10% of bone fractures may result in either nonunion or delayed union. Because nonunions remain a clinically important problem, there is interest in the utilization of tissue engineering strategies to augment bone fracture repair. Three basic biologic elements that are required for bone regeneration include cells, extracellular matrix scaffolds and biological adjuvants for growth, differentiation and angiogenesis. Mesenchymal stem cells (MSCs) are capable to differentiate into various types of the cells including chondrocytes, myoblasts, osteoblasts, and adipocytes. Due to their potential for multilineage differentiation, MSCs are considered important contributors in bone tissue engineering research. In this review we highlight the progress in the application of biomaterials, stem cells and tissue engineering in promoting nonunion bone fracture healing. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A:2551-2561, 2018.

Mussel-inspired dual-functional PEG hydrogel inducing mineralization and inhibiting infection in maxillary bone reconstruction

Infection compromises healing process after bone fracture. An anti-bacterial bone graft synthesized from polymer and mineralization components is becoming preferable for its accessibility and low cost and tunable chem-physic properties. In this study, mussel-inspired polydopamine (PDA) was used to synthesize in-situ silver nanoparticles (AgNPs) and mineralization on polyethylene hydrogel (PEG). With dual functions of anti-bacteria and graft mineralization, we found the hydrogel (AgNPs/PDA) promoted bone generation and show significant antibacterial activity. Specifically, the gel upregulated the expression of osteogenic genes of bone sialoprotein gene, alkaline phosphatase, osteocalcin and runt-related transcription factor 2. It also significantly inhibited the growth of Staphylococcus aureus and Escherichia coli. In vivo the AgNPs/PDA gel could repair maxillary bone defect efficiently.

First mid-term results after cancellous allograft vitalized with autologous bone marrow for infected femoral non-union

BACKGROUND

Surgical treatment of infected femoral non-union is challenging. Only few reports exist including autologous bone grafting (ABG) from the iliac crest promoting union. Vitalized allogeneic bone grafting (VABG) is an alternative promoting osseous healing and reconstructing bone defects. VABG contains allogeneic cancellous bone, impregnated with autologous bone marrow puncture harvested from the iliac crest. Yet, no systematic trial exists summarizing the results of septic femoral non-union using VABG analyzing the infection eradication rate, rate of osseous integration with union, and osseous remodeling.

METHODS

In this prospective non-randomized cohort study, 18 patients treated by nailing or plating for femur fractures that subsequently developed a septic non-union were included. The surgical intervention included a standardized protocol by eradicating infection first, followed by implantation VABG to promote osseous union. Main outcome measurements were radiographic union and clinical parameters.

RESULTS

Mean follow-up was 5.9 years (range: 2-8 years). Infection eradication was achieved for all patients, while union was achieved in 15 out of 18 cases (83.3 %). Mean time for union took 16.9 weeks (range: 12-24). Radiographic analysis proved osseous remodeling and full integration of VABG within 12 months for 15 patients. No infection recurrence occurred at final follow-up.

CONCLUSIONS

VABG demonstrated a high union rate without donor site morbidity as the main advantage over ABG. Sufficient osseous integration within 3 months and remodeling within 12 months are promising aspects, as no late fatigue fractures occurred. However, further trials are necessary due to the limitations of this study.

Effect of nanocrystalline hydroxyapatite socket preservation on orthodontically induced inflammatory root resorption

Objective

Orthodontically induced inflammatory root resorption (OIIRR) is considered to be an important sequel associated with orthodontic tooth movement (OTM). OTM after Socket preservation enhances the periodontal condition before orthodontic space closure. The purpose of this study is to investigate the histologic effects of NanoBone®, a new highly nonsintered porous nano-crystalline hydroxyapatite bone on root resorption following OTM.

Materials and Methods

This experimental study was conducted on four male dogs. In each dog, four defects were created at the mesial aspects of the maxillary and mandibular first premolars. The defects were filled with NanoBone®. We used the NiTi closed coil for mesial movement of the first premolar tooth. When the experimental teeth moved approximately halfway into the defects, after two months, the animals were sacrificed and we harvested the area of interest. The first premolar root and adjacent tissues were histologically evaluated. The three-way ANOVA statistical test was used for comparison.

Results

The mean root resorption in the synthetic bone substitute group was 22.87 ± 11.25×10^-4mm² in the maxilla and 21.41 ± 11.25×10^-4mm² in the mandible. Statistically, there was no significant difference compared to the control group (p>0.05).

Conclusion

The use of a substitution graft in the nano particle has some positive effects in accessing healthy periodontal tissue following orthodontic procedures without significant influence on root resorption (RR). Histological evaluation in the present study showed osteoblastic activity and remodeling environment of nanoparticles in NanoBone®.

Bone fracture healing: cell therapy in delayed unions and nonunions

Bone fracture healing impairment related to mechanical problems has been largely corrected by advances in fracture management. Better protocols, more strict controls of time and function, and hardware and surgical technique evolution have contributed to better prognosis, even in complex fractures. However, atrophic nonunion persists in clinical cases where, for different reasons, the osteogenic capability is impaired. When this is the case, a better understanding of the basic mechanisms under bone repair and augmentation techniques may put in perspective the current possibilities and future opportunities. Among those, cell therapy particularly aims to correct this insufficient osteogenesis. However, the launching of safe and efficacious cell therapies still requires substantial amount of research, especially clinical trials. This review will envisage the current clinical trials on bone healing augmentation based on cell therapy, with the experience provided by the REBORNE Project, and the insight from investigator-driven clinical trials on advanced therapies towards the future. This article is part of a Special Issue entitled Stem Cells and Bone.

Cell therapy for bone repair

When natural bone repair mechanisms fail, autologous bone grafting is the current standard of care. The osteogenic cells and bone matrix in the graft provide the osteo-inductive and osteo-conductive properties required for successful bone repair. Bone marrow (BM) mesenchymal stem cells (MSCs) can differentiate into osteogenic cells. MSC-based cell therapy holds promise for promoting bone repair. The amount of MSCs available from iliac-crest aspirates is too small to be clinically useful, and either concentration or culture must therefore be used to expand the MSC population. MSCs can be administered alone via percutaneous injection or implanted during open surgery with a biomaterial, usually biphasic hydroxyapatite/β-calcium-triphosphate granules. Encouraging preliminary results have been obtained in patients with delayed healing of long bone fractures or avascular necrosis of the femoral head. Bone tissue engineering involves in vitro MSC culturing on biomaterials to obtain colonisation of the biomaterial and differentiation of the cells. The biomaterial-cell construct is then implanted into the zone to be treated. Few published data are available on bone tissue engineering. Much work remains to be done before determining whether this method is suitable for the routine filling of bone tissue defects. Increasing cell survival and promoting implant vascularisation are major challenges. Improved expertise with culturing techniques, together with the incorporation of regulatory requirements, will open the way to high-quality clinical trials investigating the usefulness of cell therapy as a method for achieving bone repair. Cell therapy avoids the drawbacks of autologous bone grafting, preserving the bone stock and diminishing treatment invasiveness.

Exchange reamed nailing compared to augmentation compression plating leaving the inserted nail in situ in the treatment of aseptic tibial non-union: a two-centre study

BACKGROUND

A remarkable number of investigations are available treating tibial non-unions by exchange reamed nailing (ERN). Only few authors reported positive results after augmentation compression plating (ACP) for the same entity. To our knowledge no systematic study is published comparing ERN vs. ACP, so that this trial compares ACP leaving the already inserted un-reamed nail in situ against ERN in the treatment of aseptic tibial non-union, analysing success rate, time for union and operation time.

PATIENTS AND METHODS

Forty-eight patients with aseptic hypertrophic diaphyseal tibial non-union treated previously by un-reamed nailing were included retrospectively in this two-centre study. Group A consisted of 25 patients with ERN and group B of 23 patients with ACP leaving the underlying un-reamed nail in situ.

RESULTS

Mean follow-up was 3.8 years. Union was achieved in 24 out of 25 cases (96 %) for group A and in 22 out of 23 cases (95.6 %) for group B. Time needed for union varied; an average of 29 weeks for group A and 14 weeks for group B. The mean operation time for group A was 99 min, while it was 65 min for group B.

CONCLUSIONS

ERN and ACP with remaining pre-existing nail in situ are both safe and straightforward surgical procedures with equivalent high success rates of about 95 %. ACP has the advantage of less time for union and operating time in this series, but is associated with the disadvantage of requiring an additional incision and complaints associated to the plate requiring implant removal.

Attaining tibiofibular union using an inter-tibiofibular autograft. A series of 43 cases

INTRODUCTION

This study consisted of a series of 43 patients with lower leg non-union that were treated with an inter-tibiofibular autograft (ITFG).

MATERIAL AND METHODS

After reviewing the surgical technique, the overall theory behind the treatment is described, including stabilization, soft tissue repair, infection control if necessary and then performing a procedure to help achieve bone union.

RESULTS

After an average follow-up of 2 years, all the patients achieved union, but some required additional procedures. Only one patient had a delayed reactivation of the infection, which was successfully treated.

CONCLUSION

A broad set of indications for ITFG are proposed for lower leg non-union cases, in particular non-infected cases.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

High success rate for augmentation compression plating leaving the nail in situ for aseptic diaphyseal tibial nonunions

OBJECTIVES

To evaluate adjunctive compression plating leaving the previously unreamed inserted intramedullary nail (URIMN) in situ for treating a resultant diaphyseal tibial nonunion.

DESIGN

Retrospective study.

SETTING

Level 1 trauma center (University Hospital).

PATIENTS/PARTICIPANTS

Patients treated by URIMN for diaphyseal tibial fractures that developed an aseptic hypertrophic nonunion.

INTERVENTION

Dynamization of the nail and compression plating leaving the URIMN in situ.

MAIN OUTCOME MEASUREMENTS

Radiographic and clinical parameters.

RESULTS

The mean follow-up was 3.8 years (range 2-7 years). Mean time for healing was 15 weeks with a mean operation time of 63 minutes. Union occurred in 27/28 (96.4%). There were no infections.

CONCLUSIONS

This simple technique seems to have a high success rate and should be considered when a nonunion occurs after URIMN. The need for an additional incision and removal of symptomatic implants remains a disadvantage.

LEVEL OF EVIDENCE

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

Repair of long-bone pseudoarthrosis with autologous bone marrow mononuclear cells combined with allogenic bone graft

BACKGROUND AIMS

Long-bone pseudoarthrosis is a major orthopedic concern because of numerous factors such as difficulty of the treatment, high recurrence, high costs and the devastating effects on the patients' quality of life, which sometimes ends in amputation. Although the "gold standard" for the treatment of this pathology is autologous bone grafting, which has high osteogenic, osteoconductive and osteoinductive properties, this treatment presents some restrictions such as the limited amount of bone that can be taken from the patient and donor site morbidity. Bone marrow mononuclear cells (BM-MNCs) comprise progenitor and stem cells with pro-angiogenic and pro-osteogenic properties. Allogenic cancellous bone graft is a natural and biodegradable osteoconductive and osteoinductive scaffold. Combination of these two components could mimic the advantages of autologous bone grafting while avoiding its main limitations.

METHODS

Long-bone pseudoarthrosis was treated in seven patients with autologous BM-MNCs from iliac crest combined with frozen allogenic cancellous bone graft obtained from the tissue bank.

RESULTS

All patients showed complete bone consolidation 5.3 ± 0.9 months (range, 2-9 months) after cell transplantation. Moreover, limb pain disappeared in all of them. The mean follow-up was 35.8 ± 4.6 months after transplantation (range, 24-51 months) without pseudoarthrosis recurrence or pain reappearing.

CONCLUSIONS

Combination of autologous BM-MNCs and allogenic bone graft could constitute an easy, safe, inexpensive and efficacious attempt to treat long-bone pseudoarthrosis and non-union by reproducing the beneficial properties of autologous bone grafting while restricting its disadvantages.

Bone regeneration: stem cell therapies and clinical studies in orthopaedics and traumatology

Regenerative medicine seeks to repair or replace damaged tissues or organs, with the goal to fully restore structure and function without the formation of scar tissue. Cell based therapies are promising new therapeutic approaches in regenerative medicine. By using mesenchymal stem cells, good results have been reported for bone engineering in a number of clinical studies, most of them investigator initiated trials with limited scope with respect to controls and outcome. With the implementation of a new regulatory framework for advanced therapeutic medicinal products, the stage is set to improve both the characterization of the cells and combination products, and pave the way for improved controlled and well-designed clinical trials. The incorporation of more personalized medicine approaches, including the use of biomarkers to identify the proper patients and the responders to treatment, will be contributing to progress in the field. Both translational and clinical research will move the boundaries in the field of regenerative medicine, and a coordinated effort will provide the clinical breakthroughs, particularly in the many applications of bone engineering.