Mechano-bioengineering of the knee meniscus

The meniscus is a fibrocartilaginous structure of the knee joint that serves a crucial role in joint health and biomechanics. Degeneration or removal of the meniscus is known to lead to a chronic and debilitating disease known as knee osteoarthritis, whose prevalence is expected to increase in the next few decades. Meniscus bioengineering has been developed as a potential alternative to current treatment methods, wherein meniscus-like tissues are engineered using cells, materials, and biomechanical stimuli. The application of mechanical stimulation in meniscus bioengineering has presented varied results but, for the most part, it has been shown to enhance meniscus-like tissue formation. In this review, we summarized literature over the last 10 years of various mechanical stimuli applied in bioengineering meniscus tissues. The role of individual loading types is examined, and the effects on engineered meniscus are evaluated on both molecular and tissue levels. In addition, simulated microgravity is highlighted as a new area of interest in meniscus engineering, and its potential use as a disease-driving platform is discussed. Taken together, with the increased understanding of the effects of mechanical stimulation on bioengineered meniscus tissues, the most suitable loading regime could be developed for meniscus tissue engineering and osteoarthritis modeling.