Treatment of Chronic Nonunion of a Sternal Fracture With Teriparatide

Teriparatide: an innovative and promising strategy for protecting the blood-spinal cord barrier following spinal cord injury

The blood-spinal cord barrier (BSCB) is disrupted within minutes of spinal cord injury, leading to increased permeability and secondary spinal cord injury, resulting in more severe neurological damage. The preservation of blood-spinal cord barrier following spinal cord injury plays a crucial role in determining the prognosis. Teriparatide, widely used in clinical treatment for osteoporosis and promoting fracture healing, has been found in our previous study to have the effect of inhibiting the expression of MMP9 and alleviating blood-brain barrier disruption after ischemic stroke, thereby improving neurological damage symptoms. However, there are limited research on whether it has the potential to improve the prognosis of spinal cord injury. This article summarizes the main pathological mechanisms of blood-spinal cord barrier disruption after spinal cord injury and its relationship with Teriparatide, and explores the therapeutic potential of Teriparatide in improving the prognosis of spinal cord injury by reducing blood-spinal cord barrier disruption.

Bioinformatics Analysis and Experimental Validation of Differential Genes and Pathways in Bone Nonunions

Non-union fractures pose a significant clinical challenge, often leading to prolonged pain and disability. Understanding the molecular mechanisms underlying non-union fractures is crucial for developing effective therapeutic interventions. This study integrates bioinformatics analysis and experimental validation to unravel key genes and pathways associated with non-union fractures. We identified differentially expressed genes (DEGs) between non-union and fracture healing tissues using bioinformatics techniques. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were employed to elucidate the biological processes and pathways involved. Common DEGs were identified, and a protein-protein interaction (PPI) network was constructed. Fibronectin-1 (FN1), Thrombospondin-1 (THBS1), and Biglycan (BGN) were pinpointed as critical target genes for non-union fracture treatment. Experimental validation involved alkaline phosphatase (ALP) and Alizarin Red staining to confirm osteogenic differentiation. Our analysis revealed significant alterations in pathways related to cell behavior, tissue regeneration, wound healing, infection, and immune responses in non-union fracture tissues. FN1, THBS1, and BGN were identified as key genes, with their upregulation indicating potential disruptions in the bone remodeling process. Experimental validation confirmed the induction of osteogenic differentiation. The study provides comprehensive insights into the molecular mechanisms of non-union fractures, emphasizing the pivotal roles of FN1, THBS1, and BGN in extracellular matrix dynamics and bone regeneration. The findings highlight potential therapeutic targets and pathways for further investigation. Future research should explore interactions between these genes, validate results using in vivo fracture models, and develop tailored treatment strategies for non-union fractures, promising significant advances in clinical management.

[Atrophic sternum nonunion-Case report based on the nonunion scoring system]

Pseudarthrosen nach Sternotomien sind rar und meist gut im Rahmen operativer Revisionen zu behandeln. Bei fehlgeschlagenen Revisionen ist ein differenziertes Vorgehen notwendig, das sowohl die biologischen wie auch biomechanischen Rahmenbedingungen berücksichtigt. Es wird über den Fall einer therapierefraktären atrophen Pseudarthrose nach auswärtig erfolgloser Revision berichtet. Diese wurde durch ein Therapievorgehen, orientiert an den Kriterien des Non Union Scoring System (NUSS), erfolgreich behandelt. Die Versorgungsstrategie wie auch der erfolgreiche Behandlungsverlauf werden dargestellt.

Traumatic sternal fractures: a narrative review

OBJECTIVE

Traumatic sternal fractures are injuries most commonly resulting from a direct blow to the anterior chest wall or forced deceleration. The purpose of this review is to define the clinical significance of these injuries, outline their initial evaluation and work up, and review current treatment strategies available and their outcomes.

BACKGROUND

The diagnosis of traumatic sternal fractures has seen a recent rise, largely due to the increased access to computed tomography (CT) scan. Currently, there are no published guidelines to make recommendations on operative fixation for sternal fractures. This is probably related to the lack of evidence in published literature along with patient heterogeneity.

METHODS

We conducted a non-systematic review of the English literature published from January 2000 to December 2020, including meta-analyses, systematic reviews, case series and case reports regarding the diagnosis, treatment, and complications of traumatic sternal fractures. We critically analyzed the available evidence to provide an overview of the treatment and clinical outcomes of traumatic sternal fractures.

CONCLUSION

Isolated sternal fractures are commonly benign injuries that can be managed conservatively in an outpatient setting. Polytrauma patients with sternal fractures should be carefully screened for possible associated injuries. Surgical stabilization of sternal fractures is feasible and safe, and should be considered in unstable fractures, severe displacement, symptomatic malunion or non-union.

PTH1-34 improves devitalized allogenic bone graft healing in a murine femoral critical size defect

The treatment of large segmental defects of long bones resulting from trauma, infection, or bone tumor resections is a major challenge for orthopedic surgeons. The reconstruction of bone defects with acellular allografts can be used as an osteoconductive approach. However, devitalized allografts are associated with high rates of clinical failure as a result of poor intrinsic osteoinduction properties and a lack of further remodeling. Nevertheless, evidence suggests that due to its anabolic properties, teriparatide (PTH_1-34) could be effective as an adjuvant therapy for massive allograft healing. Therefore, our goal was to investigate in a murine critical-sized defect model whether the intermittent administration of PTH_1-34 improves the incorporation and revitalization of acellular structural bone allografts. Thus, a 2.5-mm critical-sized defect was established in the right femur of C57BL/6 mice, followed by the reconstruction with a devitalized cortical structural allograft. A titanium micro locking plate was applied to the anterior femoral surface and secured in place with self-tapping locking screws. Subsequently, daily doses of PTH_1-34 (30, and 40 µg/kg) or saline were administered to the mice for 14 days after surgery. The mice were maintained without PTH_1-34 therapy for an additional 7 days before being euthanized at 3 weeks post-surgery. Bone graft consolidation was assessed on radiographic images and by histomorphometric analysis. Additionally, to determine the frequency of osteoprogenitor cells in the bone marrow and their in vitro osteogenic capacity, stromal cells were isolated from the bone marrow of animals treated with 30 or 40 µg/kg/day of PTH_1-34 following the same protocol used for the experimental animals. Our results suggest that intermittent PTH_1-34 treatment at 30 µg/kg/day after femoral allograft reconstruction surgery accelerated the healing process as evidenced by new bone formation induced on endosteal and periosteal surfaces, enhanced revitalization of allogeneic graft, and increased frequency and osteogenic capacity of bone marrow stromal cells (BMSC). These findings should encourage further studies aimed at investigating the potential therapeutic use of intermittent PTH_1-34, specifically with regards to the optimal dosing regimen in clinically challenging orthopedic scenarios.

Does Teriparatide Improve Fracture Union?: A Systematic Review

We conducted an updated review of the evidence of teriparatide (TPTD) for fracture healing for the following questions. (1) Does it decrease fracture healing time?; (2) Can it be an alternative treatment for nonunion?; (3) Does it aid the union of atypical femoral fracture (AFF)? We searched PubMed, EMBASE, and Cochrane Library including “Fracture” AND “nonunion” AND “Teriparatide”. In total, 57 publications met our inclusion criteria were summarized. This systemic review of the available literature revealed that TPTD works positively with regard to enhancing fracture healing time and union of AFF. There are also many case studies on the use of TPTD could be a potential new safe treatment for nonunion with no side effects. However, level 1 studies on the evidence of TPTD are still lacking so far. Over the last decade, a growing body of evidence has accumulated suggesting that TPTD can be an adjunct to enhance fracture healing or a therapeutic option to treat nonunion, but greater evidences from large volume prospective trials are needed.