Ill add what I can to the already great advice you’ve received.
If this is an acute injury and inflamed I wouldn’t focus to much on strengthening or stretching but allow for any inflammation to dissipate. Although there is a current debate over ice or not, I always say a little ice and rest never hurt no joint. 🙂
First, I do not work for the following but I highly recommend you look into Foundation Training. www.foundationtraining.com It’s a great physical concept and program for shifting the body to more of a posterior dominant line. It will help you bring the client to a place of more glute control and a lengthened hamstring. Remember, flexibility is meaningless if you can’t recruit properly. Think effective length rather then flexibility. Most exercises can and should be done standing.
Also, I like to think of the knee as a dumb joint. It only does what the muscles around it tell it to do.
Lastly, look for a Physical Therapy platform. Essentially its a large raised gym mat that you should be able to get your client on, allowing you to do “floor work.”
I hope some of this helps. Please feel free to contact me with any more questions that might clarify my answer,
anything seated is better than standing or walking too much as it unloads the knee joints. If there is a pool available that would be great.
In addition to the already mentioned exercises you could try to do a “sitting-down/standing-up” (or box squat) exercise with a stable chair or bench that should be high enough. To facilitate this move he or she could use a TRX, ropes or strong bands to hold on through the move. This is a good way to teach how to use hamstrings and hips (pushing the butt back) when sitting down and standing up which all of my clients with knee problems can do.
I don’t have a video, but hope you can make sense of this.
a few of my favorite exercises are terminal knee extensions (http://www.youtube.com/watch?v=ZscBVtoX62U), seated straight leg raises (http://www.youtube.com/watch?v=iWGr0-dXqww) and leg curls using a dynaband (http://www.youtube.com/watch?v=j_IEOwAWyJM – I only do this one leg at a time, not both as shown in this video).