Intervertebral disc degeneration (IDD) serves as an independent risk factor for lower back pain and is closely associated with spinal musculoskeletal disorders, including lumbar disc herniation, radiculopathy, and myelopathy. , also named IL-17A, is a critical signature cytokine of T-helper 17 cells. Upon binding to

3D-printed porous implants have been attracting increased attention. Although pore size is thought to be an important factor affecting the biocompatibility of implants, there is still no accurate conclusion about the optimal pore size of implants. In searching the relevant literature, it was found, that the pore size of implants is not clearly defined in many studies. Additionally, the definition methods are different in a few studies, that have clearly defined the apertures. In the current review, the definitions of pore size in different experiments are summarized and the factors affecting the definitions are analyzed, to provide an important framework for future research and design.