Wenqing Liang,1,* Chao Zhou,2,* Xiankun Liu,1 Qiong Xie,3 Linying Xia,3 Qingping Li,3 Hongming Lin,1 Xiaochun Xiong,1 Hao Zhang,1 Zeping Zheng,1 Jiayi Zhao1 

1Department of Orthopedics, Zhoushan Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Zhoushan, 316000, People’s Republic of China; 2Department of Orthopedics, Zhoushan Guanghua Hospital, Zhoushan, 316000, People’s Republic of China; 3Medical Research Center, Zhoushan Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Zhoushan, 316000, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Wenqing Liang; Jiayi Zhao, Department of Orthopaedics, Zhoushan Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, 355 Xinqiao Road, Dinghai District, Zhoushan, 316000, Zhejiang Province, People’s Republic of China, Tel +86-580-2615027 ; +86-580-2615024, Fax +86-580-2616545, Email liangwq@usx.edu.cn; zjy2038689@sina.com

Abstract: Osteoporosis, osteoarthritis, and fractures are bone-related disorders that have a huge impact on the quality of life and healthcare systems worldwide. Traditional treatments, including bone grafts, have their limitations, with bone grafts often being rejected by the immune system and infected, making new treatments necessary. Nanopillars based on synthetic polymers have been demonstrated to be promising tools for bone regeneration and repair, showing to emulate the extracellular matrix composition, stimulate osteoblast activity and induce osteointegration. In this review, nanopillars fabrication techniques, such as electrospinning, nanoimprint lithography and self-assembly, also the state of the art of nanopillars technology are presented. Their role in modulating cellular responses via both physical and biochemical means, to enhance mineralization and to stabilize implants is also discussed. Additionally, their applications in treating bone-related disorders, eg promotion of fracture healing, augmentation of dental or orthopedic implants, and improvement of bone tissue engineering are discussed in the review. Using these focuses, each section examines opportunities and challenges (eg optimizing fabrication processes, improving biocompatibility, and investigating the integration of nanopillars with upcoming therapies like gene and stem cell therapy) for the potential of nanopillar technology. Finally, this review points out the requirement of scalable fabrication techniques, long term biocompatibility studies and multifunctional therapeutic strategies to fully employ the therapeutic applications of nanopillars in clinical scenarios. This review seeks to consolidate current knowledge of synthetic polymer based nanopillars and identify future directions for their use in bone related disorders through a comprehensive synthetic polymer nanopillar review.

Keywords: synthetic polymers, nanopillars, bone repair, osteoblast activity, osteointegration