If you are ever in a situation where you need a joint reset or you need to reset a joint check out this round-up of instructions for resetting Shoulder, Hip, Knee and Elbow joints from The Rebel Prepper. If you do a lot of hiking or camping this could come in handy to help you make it back home. Also if you live in a rural area where medical help may be far away this could be useful to pop a joint back into place to stop the pain or to make it possible to get to a doctor.
The biggest time this could be useful is in case of tornado or other weather catastrophe if someone needs a joint reset it be be hours or even days till medical help might arrive so at least if you knew how to reset a joint you could save someone hours or days of agony. Knowledge is never a bad thing to have and you just never know when something you learned along the road of life will come in handy.