Let's say that you find yourself in a situation like some character in JWR's "Patriots: A Novel of Survival in the Coming Collapse". Living in northern Idaho, you're a member of the resistance that is fighting back against the UN intrusion. As part of a three-member cell, you are often sent on missions for either reconnaissance or to show the opposing forces a little “Idaho welcome” with your heavily modified potato guns. Inevitably, one of your two companions suffers a fractured femur after falling from a lookout post. As they lay writhing on the ground, you instinctively know that by applying traction to the broken extremity, the muscle spasms will subside, giving your friend much relief. Take any piece of straight, rigid material you have with you, such as a branch from a tree, a walking stick, a ski pole, tent poles (doubled or tripled up and lashed together), etc., and lay them along the broken leg. Apply heavy padding to the inside of the groin and around the ankle in the form of folded t-shirts, etc. Now, use any form of rope or webbing available to tie two loops, one around the thigh high in the groin, and the other around the ankle, over the padding you just applied. Again, make sure they are well padded or you will cause more discomfort and risk interfering with circulation. They shouldn't be loose, but don't need to be overly tight, just enough to slip a finger or two under. Now with your remaining rope or webbing, attach the groin loop to the top tip of your straight, rigid pole. Do the same with the ankle loop, except make a simple pulley loop running from the bottom tip of the pole up through the ankle loop and back down to the tip again. In this way you can increase the amount of traction on the leg as necessary to relieve as much pain as possible. Furthermore, your rope/webbing/twine around the ankle, groin, and pole may relax with time, so you can simply unknot the pulley, pull tighter, and re-knot to keep the traction effective. When finished, lash the pole to the affected leg around the ankle and mid-calf for greater stability. One commercial option I've used is the Kendrick Traction Device (KTD) if you have the funds, but it is definitely not necessary. I would recommend watching a YouTube video of applying a KTD just in case you have questions about any of my instructions above, as obviously a video is worth 10,000 words.