Treatment Of Extensive Bone Defects Research Articles

Functionalized PLGA Microsphere Loaded with Fusion Peptide for Therapy of Bone Defects.

The challenges in the treatment of extensive bone defects are infection control and bone regeneration. Bone tissue engineering is currently one of the most promising strategies. In this study, a short biopeptide with specific osteogenic ability is designed by fusion peptide technology and encapsulated with chitosan-modified poly(lactic acid-glycolic acid) (PLGA) microspheres. The fusion peptide (FP) mainly consists of an osteogenic functional sequence (P-15) and a bone-specific binding sequence (Asp-6), which can regulate bone formation accurately and efficiently. Chitosan-modified PLGA with antimicrobial and pro-healing effects is used to achieve the sustained release of fusion peptides. In the early stage, the antimicrobial and soft tissue healing effects can stop the wound infection as soon as possible, which is relevant for the subsequent bone regeneration process. Our data show that CS-PLGA@FP microspheres have antibacterial and pro-cell migration effects in vitro and excellent pro-wound-healing effects in vivo. In addition, CS-PLGA@FP microspheres promote the expression of osteogenic-related factors and show excellent bone regeneration in a rat defect model. Therefore, CS-PLGA@FP microspheres are an efficient biomaterial that can accelerate the recovery of bone defects.

Surgical treatment of children with extensive bone defects (Literature review)

BACKGROUND: Reconstruction of extensive defects to bone tissue is one of the important problems of orthopedics and traumatology. Especially in acuteis, the problem is associated with the restoration of bone tissue in conditions of its deficiency in pediatric patients.
 AIM: The aim of the study is to analyze modern methods of surgical treatment in children with extensive bone tissue injuries based on the published literature.
 MATERIALS AND METHODS: Our report presents a review of the literature of methods of surgical treatment of extensive bone defects. The literature search was carried out in several databases such as PubMed, ScienceDirect, E-library, GoogleScholar for the period from 2005 to 2020, using the keywords given below. As a result of the search, 105 foreign and 37 domestic sources were found. After exclusion, 56 articles were analyzed, all presented works were published in the last 15 years.
 RESULTS: The gold standard for replacing bone defects is still the use of autografts, including the use of technologies on a vascular pedicle. Various types of xenografts and allografts of bone tissue are increasingly being replaced by various kinds of synthetic implants.
 CONCLUSIONS: To date, there is no single generally accepted standard for the surgical treatment of extensive bone defects. The option of surgical treatment of extensive bone tissue defects using tissue-engineered bone implants with axial blood supply seems to be extremely interesting and promising.

Efficiency of 3D Implants with Bioactive Properties for Treatment of Extensive Bone Defects: Experimental Study

Background. The problem of replacing extensive bone defects remains relevant. The use of implant structures with bioactive properties can stimulate osteogenesis, which will improve the final treatment result.The aim of the study. In an in vivo experiment, to study the possibility of replacing an extensive defect in the bone diaphysis with a personal bioactive cellular 3D implant and evaluate the long-term results of its use.Materials and Methods. In an in vivo experiment, adult large mongrel dogs (n = 8) were modeled with an extensive segmental defect of the tibial diaphysis measuring 4 cm. The defect was replaced with a cellular bioactive 3D implant made of titanium alloy Ti6Al4V, manufactured using the additive technology. The diameter of the cells was 1.5 mm on average. The walls of the implant had pores of 100– 300 μm in size. The inner and outer surfaces were coated with a calcium phosphate layer formed by micro-arc oxidation. The primary fixation was provided with the Ilizarov apparatus. In the early postoperative period, antibiotic prophylaxis with broad-spectrum drugs was performed. Clinical, X-ray, histological and statistical methods were used to analyze the results. The main control points were considered: the end of external fixation with the Ilizarov apparatus, after 180 days and 1 year after the termination of external fixation.Results. During the experiment, the death of animals and complications were not observed. The spatial location of the implant was preserved. The formation of a strong bone-implantation block occurred 37.2±6.3 days after the operation. During this period, the external fixation apparatus was dismantled. Osseointegration was provided under conditions of sufficient primary mechanical stability, due to the cellular structure of the implant, the presence of pores on its walls, and the osteoinductive properties of the applied calcium phosphate coating. The achieved degree of osseointegration persisted in long-term periods (6 months and 1 year after the termination of external fixation). The osteoinductive properties of the calcium phosphate coating were confirmed by the expression of osteopontin cells at all stages of the experiment. Outflow of Ca and P from bone fragments was not observed. An elastic sheath was formed on the surface of the implant, similar in structure to the periosteum. The implant cells were filled with a well-vascularized bone substrate. In the projection of the intermediate zone, compact bone tissue was formed, and in the projection of the medullary canal — reticulofibrous bone marrow. This indicates the possibility of organotypic remodeling of bone structures inside the implant.Conclusion. The results of the study showed the effectiveness of using a bioactive cellular 3D implant to replace an extensive defect in the shaft of the bone. The architectonics and osteoinductive properties of the implant surface contributed to the formation of complete osseointegration in a short time, while maintaining the achieved result in long-term periods.

The approach of ameloblastoma of the mandible: a case treated by hyperbaric oxygen therapy and bone graft reconstruction

Reconstruction of mandibular defects after tumor resection is a challenge to the head and neck surgeon because of associated functional and esthetic problems. The intention of mandibular reconstructive surgery is to achieve maximum possible functionality, which means the restoration of masticatory function and speech with a good esthetic result. Hyperbaric oxygen therapy (HBO) is already a well-accepted adjunct in the treatment of extensive bone defects. It has been shown to enhance osteogenesis and improve soft tissue wound healing in a variety of circumstances. The following case report describes a 29-year-old woman who was diagnosed with mandibular ameloblastoma. The treatment of choice is resection with mandibular base maintenance. The patient underwent 10 sessions of hyperbaric oxygen therapy and subsequent nonvascularized iliac crest graft. Six months after, mandibular reconstruction is possible to observe the preservation of mandibular contouring and facial esthetics. A panoramic radiograph revealed good positioning of the bone graft and volume maintenance. The mandibular reconstruction is extremely important for the rehabilitation of the patient who underwent bone resection. The restoration of mandibular function and facial esthetics is essential to maintain the quality of life. The use of HBO in mandibular reconstruction is an important adjunct to successful treatment, however, more studies are needed to establish the best modalities of rehabilitation.

Bone tissue engineering with human stem cells.

Treatment of extensive bone defects requires autologous bone grafting or implantation of bone substitute materials. An attractive alternative has been to engineer fully viable, biological bone grafts in vitro by culturing osteogenic cells within three-dimensional scaffolds, under conditions supporting bone formation. Such grafts could be used for implantation, but also as physiologically relevant models in basic and translational studies of bone development, disease and drug discovery. A source of human cells that can be derived in large numbers from a small initial harvest and predictably differentiated into bone forming cells is critically important for engineering human bone grafts. We discuss the characteristics and limitations of various types of human embryonic and adult stem cells, and their utility for bone tissue engineering.

Treatment of Large Femoral Bone Defects - 15-Year Experiences with the Cementless Bicontact Revision Stem with Distal Interlocking

With the steady growth in the number of hip arthroplasty revision operations, the concept and long-term results of the Bicontact revision stem with distal interlocking for the treatment of extensive femoral bone defects were investigated in this prospective study. The first 156 stem revision operations performed between January 1992 and December 2002 were evaluated. The indication for operation was aseptic loosening in 133, stem fracture in 14, recurrent dislocation in 2 and reimplantation following Girdlestone removal of a septic prosthesis in 7. The cup component was revised at the same time in 74 cases. Higher-grade femoral bone defects were found intraoperatively in 66 %. The average age of the patients was 71.4 (34 - 88) years at operation and 76.9 (44 - 94) years at the last follow-up. The average period until follow-up, re-revision or loss to follow-up was 5.54 (0.1 - 14.9) years. The clinical and radiological follow-up rate (with reference to the total number of patients) was 35 % (55 von 156), and 51 % (55 of 107) with reference to patients still living. The median Harris Hip Score was 63.7 points. In the observation period, 12 stems were exchanged for a cemented standard stem, 5 stems were removed because of infection and 2 stems were revised because of periprosthetic fracture. The calculated survival rate for the stems after 14.9 years was 85.9 %. The 15-year results confirm the biomechanical concept of the Bicontact revision stem with optional distal interlocking for the treatment of extensive bone defects in stem revision surgery.

Aplicaciones de la hidroxiapatita coralina HAP-200 como material de implante óseo en ortopedia

The coralina hydroxyapatites developed in Cuba have been evaluated in odontology, but a study of their use in orthopedic cases has not been carried out until now, The present work shows the results of the use of porous hydroyapatite coralina HAP-200 in traumatology and orthopaedics. It includes 10 patients with different tumoral bone diseases which were treated at C.J. Finlay Hospital. The radiographic, haematological and ciinical evolution confirmed the excellent properties of this biomaterial for the regeneration of bone tissue and suggests its possible use in the treatment of extensive bone defects.