Specific knee exercises post meniscul injury?

I had an estimated 15-30% of my medial meniscus removed in 2004 due to a bucket handle tear. I was told to strengthen my legs to minimize risk of further injury. Up until Dec 2011, my only leg exercise was daily walking, very sporadic bike riding and daily martial arts with light kicking.

I reinjured it in Dec during a martial arts pivot or kick. Not acute. Just started hurting to the point that I stopped training. I started riding my bike almost daily. After 6 wks, my thighs were noticeably bigger (though I'm thin by nature) and knee feeling pretty good. So I started resumed my martial arts, stepped it up on my bike climbing hills in a high gear and reinjured it yet again. It was like I was back to square one. After 2-3 more wks of mild bike riding, there was only mild improvement so I saw an orthopod. He took x-rays but felt an MRI was not needed. X-rays indicated a very, very slight narrowing in the area where I had meniscul surgery. Dr said it was indicative of arthritis but that it wasn't enough to be concerned with.

Dr wasn't sure what was going on for sure but told me to continue strengthening my knee and to come back if that didn't help.

I'm done with martial arts...for now, maybe good. With a love of backpacking (ultralight) and hiking, this has me scared. As such, I am committed to doing what it takes to be able to continue for as long as possible.

Besides riding my bike, what other exercises should I be doing? I have a weight bench for leg extensions and curls. Would that be beneficial?

I am an otherwise healthy 43 yr old male at 6' and 150 lbs.

Advice would be greatly appreciated!

Thanks.

[John Gallucci Jr, MS, ATC, PT, DPT]

It would be my recommendation to see a physical therapist at this point to help educate you in the proper lower extremity exercises to increase stability at the knee joint during the twisting motions that seem to be effecting you the most.  The physical therapist will be able to contour the exercises based on your presentation and be right there to modify them accordingly to prevent increased irritation with certain mechanical movements.  There are many different lower extremity exercises, however, your body may become irritated with certain movements that would otherwise be common strengthening motions for the otherwise "healthy" individual.  If you would like I could refer you to a few physical therapy centers in your region.
Best in Health,
JAG