Treatment of forearm diaphyseal non-union: Autologous iliac corticocancellous bone graft and locking plate fixation

Biomaterials for bone defect repair: Types, mechanisms and effects

Bone defects or bone discontinuities caused by trauma, infection, tumours and other diseases have led to an increasing demand for bone grafts and biomaterials. Autologous bone grafts, bone grafts with vascular tips, anastomosed vascular bone grafts and autologous bone marrow components are all commonly used in clinical practice, while oversized bone defects require the use of bone tissue engineering-related biomaterials to repair bone defects and promote bone regeneration. Currently, inorganic components such as polysaccharides and bioceramics, as well as a variety of bioactive proteins, metal ions and stem cells can be loaded into hydrogels or 3D printed scaffold materials to achieve better therapeutic results. In this review, we provide an overview of the types of materials, applications, potential mechanisms and current developments in the repair of bone defects.

Synergistic effects of autologous platelet-rich plasma combined with an extracorporeal shock wave in treatment of long diaphysis aseptic nonunion

INTRODUCTION

Union of long bone fractures is a complicated biological mechanism affected by numerous systemic and local variables. Disruption of any of these components may result in fracture nonunion. There are various types of clinically available treatment strategies for aseptic nonunion. Both activated platelet plasma and extracorporeal shock waves play important roles in fracture healing. This study aimed to investigate the interaction of platelet-rich plasma (PRP) and extracorporeal shock wave (ESW) in bone healing of nonunion.

HYPOTHESIS

PRP and ESW have synergistic effects in treating long bone nonunion.

METHODS

Between January 2016 and December 2021, a total of 60 patients with established nonunion of a long bone (18 tibias, 15 femurs, 9 humerus, 6 radii, and 12 ulnae) were included in this study, comprising 31 males and 29 females, ranging from 18 to 60 years old. Patients with bone nonunion were separated into two groups: PRP alone (Monotherapy group) and those treated with PRP combined with ESW (Combined treatment group). The two groups were compared to assess the therapeutic benefits, callus development, local problems, bone healing time, and Johner Wruhs functional classification of operated limbs.

RESULTS

Fifty-five patients were followed up, 5 patients were lost to follow-up, two in the PRP group and three in the PRP+ESW group, the follow-up time varied from 6 to 18 months, with an average of 12.7±5.2 months. At 8, 12, 16, 20, and 24 weeks following intervention, the callus score in the monotherapy group was significantly lower than in the combined treatment group (p<0.05). Both groups had no swelling and infection in the soft tissue of the nonunion operation site. In the PRP+ESW group, the fracture union rate was 92.59% and the healing time was 16.3±5.2 weeks. In the PRP group, the fracture union rate was 71.43% and the healing time was 21.5±3.7 weeks. The clinical healing time of the monotherapy group was significantly longer than the combined treatment group (p<0.05). All the nonunion patients with no signs of healing were treated with revision surgery. The excellent and good rate of Johner-Wruhs functional classification of affected limbs in the monotherapy group was significantly lower than in the combined treatment group (p<0.05).

CONCLUSION

PRP combined with ESW has a certain synergistic effect in treating aseptic nonunion after fracture surgery. It can significantly improve the formation of new bone, it is a minimally invasive and effective strategy to treat aseptic nonunion in a clinical setting.

LEVEL OF EVIDENCE

III, retrospective, single-centre, case-control study.

Union, complication, reintervention and failure rates of surgical techniques for large diaphyseal defects: a systematic review and meta-analysis

To understand the potential and limitations of the different available surgical techniques used to treat large, long-bone diaphyseal defects by focusing on union, complication, re-intervention, and failure rates, summarizing the pros and cons of each technique. A literature search was performed on PubMed, Web of Science, and Cochrane databases up to March 16th, 2022; Inclusion criteria were clinical studies written in English, of any level of evidence, with more than five patients, describing the treatment of diaphyseal bone defects. The primary outcome was the analysis of results in terms of primary union, complication, reintervention, and failure rate of the four major groups of techniques: bone allograft and autograft, bone transport, vascularized and non-vascularized fibular graft, and endoprosthesis. The statistical analysis was carried out according to Neyeloff et al., and the Mantel–Haenszel method was used to provide pooled rates across the studies. The influence of the various techniques on union rates, complication rates, and reintervention rates was assessed by a z test on the pooled rates with their corresponding 95% CIs. Assessment of risk of bias and quality of evidence was based on Downs and Black’s “Checklist for Measuring Quality” and Rob 2.0 tool. Certainty of yielded evidence was evaluated with the GRADE system. Seventy-four articles were included on 1781 patients treated for the reconstruction of diaphyseal bone defects, 1496 cases in the inferior limb, and 285 in the upper limb, with trauma being the main cause of bone defect. The meta-analysis identified different outcomes in terms of results and risks. Primary union, complications, and reinterventions were 75%, 26% and 23% for bone allografts and autografts, 91%, 62% and 19% for the bone transport group, and 78%, 38% and 23% for fibular grafts; mean time to union was between 7.8 and 8.9 months in all these groups. Results varied according to the different aetiologies, endoprosthesis was the best solution for tumour, although with a 22% failure rate, while trauma presented a more composite outcome, with fibular grafts providing a faster time to union (6.9 months), while cancellous and cortical-cancellous grafts caused less complications, reinterventions, and failures. The literature about this topic has overall limited quality. However, important conclusions can be made: Many options are available to treat critical-size defects of the diaphysis, but no one appears to be an optimal solution in terms of a safe, satisfactory, and long-lasting outcome. Regardless of the bone defect cause, bone transport techniques showed a better primary union rate, but bone allograft and autograft had fewer complication, reintervention, and failure rates than the other techniques. The specific lesion aetiology represents a critical aspect influencing potential and limitations and therefore the choice of the most suitable technique to address the challenging large diaphyseal defects.

Octacalcium Phosphate Bone Substitute (Bontree®): From Basic Research to Clinical Case Study

Bone grafts used in alveolar bone regeneration can be categorized into autografts, allografts, xenografts, and synthetic bones, depending on their origin. The purpose of this study was to evaluate the effect of a commercialized octacalcium phosphate (OCP)-based synthetic bone substitute material (Bontree®) in vitro, in vivo, and in clinical cases. Material characterization of Bontree® granules (0.5 mm and 1.0 mm) using scanning electron microscopy and X-ray diffraction showed that both 0.5 mm and 1.0 mm Bontree® granules were uniformly composed mainly of OCP. The receptor activator of NF-κB ligand (RANKL) and alkaline phosphatase (ALP) activities of MG63 cells were assessed and used to compare Bontree® with a commercial biphasic calcium phosphate ceramic (MBCP+TM). Compared with MBCP+TM, Bontree® suppressed RANKL and increased ALP activity. A rabbit tibia model used to examine the effects of granule size of Bontree® grafts showed that 1.0 mm Bontree® granules had a higher new bone formation ability than 0.5 mm Bontree® granules. Three clinical cases using Bontree® for ridge or sinus augmentation are described. All eight implants in the three patients showed a 100% success rate after 1 year of functional loading. This basic research and clinical application demonstrated the safety and efficacy of Bontree® for bone regeneration.