Chondrocyte content in articular cartilage is very low. Only 2% to 5% of the tissue volume consists of chondrocytes [1]. Yet, these cells are responsible for maintenance of the tissue. Hence, the loss of chondrocytes that is often occurring at an early stage of cartilage degeneration is detrimental to articular cartilage. Excessive mechanical loading is known to be a cause of cell death. However, mechanical thresholds beyond which chondrocyte apoptosis would be induced are unknown.