Ouch hope you recovered from that. If its not too personal or painful can you elaborate on that experience? Specifically how did you use the knife to extricate yourself?
The "what if you get trapped under a rock" scenario gets brought up a lot in the "folder vs. fixed blade" and "large knife versus hatchet and/or small knife" threads.It would be nice to hear the details of an actual real life experience and not just the usual "what if" speculations.
Sure can, tholiver.
First and most fortunately, I didn't have to extricate myself with my knife. At the time of the leg crushing and trapping, I was accompanied by one of the survival instructors, an ex-Army SF and Air Force PJ (he cross-trained from one branch to the other). The rock, which was later estimated by the university to weigh between 600-800lbs, was flat in shape. It came to rest both on my leg and a neighboring boulder, which itself was pitched in the middle. This lower boulder acted as a fulcrum, allowing the class instructor to push up on one side of the trapping boulder, causing it to slide back off my leg. Think of a teeter-totter that's perfectly balanced and resting horizontally: it would take very little effort to push up on one side, dropping the others end back. That's how the boulder was moved from my leg & foot. Not to mention that the instructor was very strong and regularly lifted weights, focusing on heavy lifting.
So, I was extricated due to a seeming fluke in where the boulder came to a rest. I attribute it to divine intervention. Had I been by myself, I may have been able to reach the boulder's edge with my knife (at that time, I was carrying a Cold Steel SRK) and lever it off of my leg. I would've been blowing frantically on my signal whistle for a long time, though, I can tell you that!

Most likely in my case, had the signal whistle failed to get anyone's attention, I'd have had to cut my leg off, tourniquet it, build a fire, and pray for a quick extraction. Even with the immediate, expert rescue I had, it took 3 hours to get to the university hospital, my state's only level 1 trauma center.
By the by, the surgeon had to wait 3 days before he could do the first surgery on my leg. It was so swollen, they had to wait and see if amputation was indicated. When the surgeon was finally able to go in, he said that all of the bone shards had been put perfectly in place by the instructors' expert traction on the leg when in the mountains. Had the traction been done by anyone less capable and experienced, he would've had to amputate. Yes, I believe in God and I believe He saved my leg.
As for my conviction on the necessity of carrying a strong fixed blade in the wilderness, getting my leg crushed by a boulder (ironically, while taking a wilderness skills course

) proved to me that *it*, whatever *it* may be, can and does happen to ordinary people. A strong, fixed blade knife is a very basic and useful tool, particularly when out of civilization.
If you have any more questions, tholiver, or anyone else for that matter, feel free to ask! I'm currently recovering slowly but nicely from my third surgery, a total reconstruction. Yep, 5 years after the fact and I'm starting to heal up...

But, I'm not shy about talking 'bout it.