The indications and donor-site morbidity of tibial cortical strut autografts in the management of defects in long bones

Magnesium-oxide-enhanced bone regeneration: 3D-printing of gelatin-coated composite scaffolds with sustained Rosuvastatin release

Critical-size bone defects are one of the main challenges in bone tissue regeneration that determines the need to use angiogenic and osteogenic agents. Rosuvastatin (RSV) is a class of cholesterol-lowering drugs with osteogenic potential. Magnesium oxide (MgO) is an angiogenesis component affecting apatite formation. This study aims to evaluate 3D-printed Polycaprolactone/β-tricalcium phosphate/nano-hydroxyapatite/ MgO (PCL/β-TCP/nHA/MgO) scaffolds as a carrier for MgO and RSV in bone regeneration. For this purpose, PCL/β-TCP/nHA/MgO scaffolds were fabricated with a 3D-printing method and coated with gelatin and RSV. The biocompatibility and osteogenicity of scaffolds were examined with MTT, ALP, and Alizarin red staining. Finally, the scaffolds were implanted in a bone defect of rat's calvaria, and tissue regeneration was investigated after 3 months. Our results showed that the simultaneous presence of RSV and MgO improved biocompatibility, wettability, degradation rate, and ALP activity but decreased mechanical strength. PCL/β-TCP/nHA/MgO/gelatin-RSV scaffolds produced sustained release of MgO and RSV within 30 days. CT images showed that PCL/β-TCP/nHA/MgO/gelatin-RSV scaffolds filled approximately 86.83 + 4.9 % of the defects within 3 months and improved angiogenesis, woven bone, and osteogenic genes expression. These results indicate the potential of PCL/β-TCP/nHA/MgO/gelatin-RSV scaffolds as a promising tool for bone regeneration and clinical trials.

Effect of autologous platelet-rich plasma on new bone formation and viability of a Marburg bone graft

This study aimed to compare the new bone formation, the process of remodeling, and the viability of bone grafts, using a combination of platelet-rich plasma (PRP) and Marburg bone graft versus bone grafts without any additional elements. For this study, 48 rabbits (with 24 rabbits in each group) were used. Bone defects were made in the femur, and the bone graft used was the human femoral head prepared according to the Marburg Bone Bank. Rabbits were divided into the following groups: heat-treated bone graft (HTBG group) and HTBG with PRP (HTBG + PRP group). After 14, 30, and 60 days post-surgery, the assessment of the results involved X-ray, histopathological, and histomorphometric analyses. The greater new bone formation was detected in the HTBG + PRP group on the 14 and 30 day (p < 0.001). Furthermore, the group using bone grafts with PRP demonstrated notably enhanced remodeling, characterized by stronger bone integration, more significant graft remineralization, and a circular pattern of newly formed bone. The PRP-bone graft complex improves bone tissue repair in the bone defect in the initial stages of bone regeneration. PRP has been identified to enhance the remodeling process and amplify the osteoconductive and osteoinductive capabilities of HTBGs.

Reconstruction After En Bloc Resection of a Distal Radius Tumor. An Updated and Concise Review

The distal radius is rarely affected by either primary or metastatic bone cancers. The most frequent tumors of the distal radius are giant cell tumors, which are benign tumors with the propensity to invade. En bloc excision of giant cell tumors of the distal radius achieves a low recurrence rate but compromises the wrist joint, necessitates a significant reconstruction, and has functional consequences. Reconstruction after en bloc resection of a distal radius bone tumor is challenging. Furthermore, orthopedic oncologists disagree on treating such long bone anomalies most effectively. The present article summarizes the various biological and non-biological reconstruction techniques performed after en bloc resection of a distal radius tumor, discusses the advantages and disadvantages of each reconstruction strategy, and summarizes several case studies and case reports.

Bone-Graft Resorption Reduced by the Induced Membrane Technique and Factors Affecting Volumetric Changes: An Analysis of 120 Serial Computed Tomographic Scans in 40 Patients

BACKGROUND

Little is known about the volumetric changes of grafted bone over time when using the induced membrane technique. This study investigates the volumetric changes of bone graft using serial computed tomographic (CT) scans following the induced membrane technique.

METHODS

Patients with critical-sized bone defects had serial CT scans after undergoing bone-grafting using the induced membrane technique. CT scans to evaluate the volume of bone graft were obtained immediately postoperatively and at 6 and 12 months. The change in the volume of bone graft was determined at 6 and 12 months postoperatively. Patient demographic characteristics, the location and composition of the bone graft, and the type of fixation construct were analyzed.

RESULTS

Forty patients met inclusion criteria. There were 27 tibiae and 13 femora with a mean size defect of 8.6 cm (range, 2.5 to 20.6 cm). Of these patients, 21 received autograft with cancellous bone graft and 19 received mixed autogenous bone with demineralized bone matrix (DBM) at a mean time of 17 weeks after the membrane formation. For the first 6 months, there was an overall osseous resorption of -9.9%. The overall graft volume from 6 to 12 months demonstrated an increase of osseous volume by +1.6%. For the entire 12-month period, there was a mean graft volume resorption of -8.3%. A correlation was found between the early volumetric changes of grafted bone and the percentage of DBM in the graft mixture. A correlation was also found between the late volumetric changes and the location of defect or the type of fixation.

CONCLUSIONS

At 1 year after use of the induced membrane technique for the treatment of a critical-sized bone defect, resorption of the grafted bone averaged -8.3%. The volumetric changes were influenced by the property of the grafted bone, the fixation construct, and the location of the defect.

LEVEL OF EVIDENCE

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

Recent developments in biomaterials for long-bone segmental defect reconstruction: A narrative overview

Reconstruction of long-bone segmental defects (LBSDs) has been one of the biggest challenges in orthopaedics. Biomaterials for the reconstruction are required to be strong, osteoinductive, osteoconductive, and allowing for fast angiogenesis, without causing any immune rejection or disease transmission. There are four main types of biomaterials including autograft, allograft, artificial material, and tissue-engineered bone. Remarkable progress has been made in LBSD reconstruction biomaterials in the last ten years.

THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE

Our aim is to summarize recent developments in the divided four biomaterials utilized in the LBSD reconstruction to provide the clinicians with new information and comprehension from the biomaterial point of view.

Autologous bone marrow clot as an alternative to autograft for bone defect healing

Objectives

Long bone defects often require surgical intervention for functional restoration. The ‘gold standard’ treatment is autologous bone graft (ABG), usually from the patient’s iliac crest. However, autograft is plagued by complications including limited supply, donor site morbidity, and the need for an additional surgery. Thus, alternative therapies are being actively investigated. Autologous bone marrow (BM) is considered as a candidate due to the presence of both endogenous reparative cells and growth factors. We aimed to compare the therapeutic potentials of autologous bone marrow aspirate (BMA) and ABG, which has not previously been done.

Methods

We compared the efficacy of coagulated autologous BMA and ABG for the repair of ulnar defects in New Zealand White rabbits. Segmental defects (14 mm) were filled with autologous clotted BM or morcellized autograft, and healing was assessed four and 12 weeks postoperatively. Harvested ulnas were subjected to radiological, micro-CT, histological, and mechanical analyses.

Results

Comparable results were obtained with autologous BMA clot and ABG, except for the quantification of new bone by micro-CT. Significantly more bone was found in the ABG-treated ulnar defects than in those treated with autologous BMA clot. This is possibly due to the remnants of necrotic autograft fragments that persisted within the healing defects at week 12 post-surgery.

Conclusion

As similar treatment outcomes were achieved by the two strategies, the preferred treatment would be one that is associated with a lower risk of complications. Hence, these results demonstrate that coagulated BMA can be considered as an alternative autogenous therapy for long bone healing.

Cite this article: Z. X. H. Lim, B. Rai, T. C. Tan, A. K. Ramruttun, J. H. Hui, V. Nurcombe, S. H. Teoh, S. M. Cool. Autologous bone marrow clot as an alternative to autograft for bone defect healing. Bone Joint Res 2019;8:107–117. DOI: 10.1302/2046-3758.83.BJR-2018-0096.R1.