How is Biodegradable Scaffold Effective in Gap Non-union? Insights from an Experiment

Treatment of Bone Defects and Nonunion via Novel Delivery Mechanisms, Growth Factors, and Stem Cells: A Review

Bone nonunion following a fracture represents a significant global healthcare challenge, with an overall incidence ranging between 2 and 10% of all fractures. The management of nonunion is not only financially prohibitive but often necessitates invasive surgical interventions. This comprehensive manuscript aims to provide an extensive review of the published literature involving growth factors, stem cells, and novel delivery mechanisms for the treatment of fracture nonunion. Key growth factors involved in bone healing have been extensively studied, including bone morphogenic protein (BMP), vascular endothelial growth factor (VEGF), and platelet-derived growth factor. This review includes both preclinical and clinical studies that evaluated the role of growth factors in acute and chronic nonunion. Overall, these studies revealed promising bridging and fracture union rates but also elucidated complications such as heterotopic ossification and inferior mechanical properties associated with chronic nonunion. Stem cells, particularly mesenchymal stem cells (MSCs), are an extensively studied topic in the treatment of nonunion. A literature search identified articles that demonstrated improved healing responses, osteogenic capacity, and vascularization of fractures due to the presence of MSCs. Furthermore, this review addresses novel mechanisms and materials being researched to deliver these growth factors and stem cells to nonunion sites, including natural/synthetic polymers and bioceramics. The specific mechanisms explored in this review include BMP-induced osteoblast differentiation, VEGF-mediated angiogenesis, and the role of MSCs in multilineage differentiation and paracrine signaling. While these therapeutic modalities exhibit substantial preclinical promise in treating fracture nonunion, there remains a need for further research, particularly in chronic nonunion and large animal models. This paper seeks to identify such translational hurdles which must be addressed in order to progress the aforementioned treatments from the lab to the clinical setting.

Collagen/Nano-hydroxyapatite Composite Scaffold Application with Exchange Reamed Nailing Accelerates Bone Union and Improves Quality of Life in Atrophic Femoral Shaft Nonunions: A Retrospective Comparative Study

BACKGROUND

Our aim in this study was to evaluate the effect of exchange intramedullary nailing in femoral shaft atrophic nonunions and the use of collagen/nano-hydroxyapatite composite scaffold applied in addition to the cancellous iliac crest autograft on the union, return to work, and quality of life.

MATERIALS AND METHODS

Fifty-four patients with an atrophic nonunion in the isthmic region of the femoral shaft were included in the study. The patients were divided into two groups. Group A consisted of 24 patients who underwent collagen/nano-hydroxyapatite composite scaffold in addition to exchange intramedullary nailing and iliac autograft, while group B consisted of 30 patients without scaffold. Short Form-36 (SF-36) questionnaire scores, union rates, time to union, return to work were complications were compared.

RESULTS

Mean age of patients was 47.5 ± 14.1. The mean follow-up period was 3.56 ± 1.88 years. There was no statistically significant difference between Group A and B in terms of age, gender, smoking and alcohol use, and trauma mechanism. Time to union and return to work were statistically significantly shorter in Group A than in Group B (p = 0.004, p = 0.001). All of the SF-36 survey scores at month six were better in Group A. In the first year, mental health and general health perception were still statistically better in group A (p = 0.009, p = 0.008).

CONCLUSION

In the treatment of atrophic nonunions of the femoral shaft isthmic region, the use of collagen/nano-hydroxyapatite composite scaffolds together with exchange intramedullary nailing affects the union positively. This positive effect also brings about earlier return to work and better quality of life.