The video is almost certainly a fake, but it has happened (well....the wing hasn't been completely lost.....but it's come loose)
Here's an account of a Zlin's wing partially falling off and having to fly an inverted circuit to keep it on before rolling out on final.....
IT all really depends on the amount of thrust availabel to maintain the knifedge....and not many aircraft (even high performance aerobatic aircraft) have enough to do so for the time in the video (assuming we're talking about the same thing). It can however happen in RC aircraft which generally have a very high thrust to weight ratio.
Here's a nice video of a very skilful landing following the sme kind of incident....just this time it's RC

.mic
.mic