Joint Stretch

Hilton’s Law states,

The nerve supplying a joint supplies also the muscles which move the joint and the skin covering where those muscles attach to the bone.
John Hilton (1804-1878), an English Surgeon who studied anatomy

Due to this major neuromuscular law of body function, stretching a joint is very helpful to encourage the body to release tensions from another focus—from the joint to the muscles. This passive work helps restore the normal range of motion of the joint addressed.