At what body temperature does rigidity begin in hypothermic conditions?

Rigidity in hypothermic conditions, also known as "cold stiffening," typically begins at a body temperature of around 90 degrees Fahrenheit. As the body temperature drops due to hypothermia, the normal metabolic processes and muscle function decline. Below this temperature, muscle tissues begin to lose their ability to contract and relax, leading to increased stiffness and rigidity.

In the context of hypothermia, it is critical to recognize not only the temperature at which rigidity occurs but also the progression of symptoms as the body cools. At temperatures lower than 90 degrees, the risk of severe complications increases significantly, and muscle function is further impaired. This understanding is essential for emergency responders when assessing and treating individuals suffering from hypothermia.