01959nas a2200229   4500000000100000000000100001008004100002260001500043653000900058653002200067653001700089653002000106100002100126700001600147700001900163700002300182245008900205300001200294490000700306520140200313022001401715       2021                            d  c2021-02-0310aBone10acancer metastasis10amicrofluidic10aorgan on-a-chip1 aAmin Mansoorifar1 aRyan Gordon1 aRaymond Bergan1 aLuiz E. Bertassoni00aBone-on-a-chip: microfluidic technologies and microphysiologic models of bone tissue  a20067960 v313 aBone is an active organ that continuously undergoes an orchestrated process of remodeling throughout life. Bone tissue is uniquely capable of adapting to loading, hormonal, and other changes happening in the body, as well as repairing bone that becomes damaged to maintain tissue integrity. On the other hand, diseases such as osteoporosis and metastatic cancers disrupt normal bone homeostasis leading to compromised function. Historically, our ability to investigate processes related to either physiologic or diseased bone tissue has been limited by traditional models that fail to emulate the complexity of native bone. Organ-on-a-chip models are based on technological advances in tissue engineering and microfluidics, enabling the reproduction of key features specific to tissue microenvironments within a microfabricated device. Compared to conventional in-vitro and in-vivo bone models, microfluidic models, and especially organs-on-a-chip platforms, provide more biomimetic tissue culture conditions, with increased predictive power for clinical assays. In this review, we will report microfluidic and organ-on-a-chip technologies designed for understanding the biology of bone as well as bone-related diseases and treatments. Finally, we discuss the limitations of the current models and point toward future directions for microfluidics and organ-on-a-chip technologies in bone research.  a1616-301X