Mechanical stimulation of human chondrocytes by ultrasound as a bioinspired strategy to regenerate knee cartilage

Abstract

[Excerpt] Articular cartilage is naturally subjected to mechanical forces during knee joint loading. A constant and physiological loading of articular cartilage is essential for chondrocytes, the resident cells, that sense the mechanical deformations, activating their intracellular mechanisms to regulate and maintain the tissue homeostasis. However, either excessive or low magnitude mechanical loading may disturb this homeostasis and induce cartilage damage [1]. Cartilage injuries affect, approximately, 900,000 patients in USA per year, leading to more than 200,000 surgical procedures, with an annual incidence growth of 5% [2]. Current treatments fail in restoring articular cartilage, only delaying the progression of its degeneration, which ultimately results in osteoarthritis. Knee osteoarthritis is a major public health concern and one of the major causes of disability worldwide, affecting 7% of the global population and this is expected to increase over the years [3]. There is a significant economic and clinical need for new therapies that could induce cartilage regeneration or, at least, stop further degeneration by stimulating the natural cartilage biomechanical environment. [...]