The lumbar disc supports very high loads, as cadaver studies and in vivo demonstrated. In these latter studies, a pressure probe was inserted into the third lumbar disc of healthy volunteers. The pioneering works of Nachemson [1] have been replicated, and their results have been updated [2, 3]. Today, it can be considered that, in an adult weighing 65–75 kg, on the third or fourth lumbar disc in a sitting position, there is a load of 10 to 15 kg/cm2 (currently, pressure is measured with the less popular Pascal: 1 Mega Pascal (MPa) is equivalent to 10.2 kg/cm2). The pressure drops by 30% in static and 50% in supine position. The intradiscal pressure can rise to over 23 kg/cm2 when lifting an object weighing 20 kg with a flexed trunk.