Injured knee/ACL?

Happy 2012 everyone.

I know it must be difficult to assess an injury from a description alone, but I can't get to a physio for another week or so, and I would like to hear the opinion of people here.

I hurt my knee over a week ago in a situation similar to this (Leglock - Wikipedia, the free encyclopedia). At the time I heard a snap/pop, but it was not loud and I experienced no pain. I completed the training session and ent to work for the day.

It was only that evening did I notice that my knee started "weird". There was no noticeable swelling, still no pain, and no real instability (as far as I could tell), my knee just felt tight across the front of the joint. The only time I feel any pain (and it' more like mild discomfort than pain) is when I flex/bend my knee past 90 degrees - just feels a bit weak through the back of the joint.

I'm always getting injured (once I heard a similar "pop" come from my elbow, and it was fine), and often I have often stopped training and rested which has turned out to be unnecessary, so I have continued to train. I have completed a few Jiu - Jitsu sessions, two kettle bell classes, a few weights sessions (I pressed 150kg with my legs), all without pain during or post workout.

So, considering all this, I have assumed that whatever injury I have, it couldn't be that bad. Therefore, does anyone think it is likely that I could do serious damage to my knee? Moreover, is it likely to be damage to the ACL or could it just be muscular?

Any feedback is appreciated.

The complete absence of any swelling or pain whatsoever and the fact that I would also imagine weights of 150kg's would flare-up a ligament/meniscal injury make me think its unlikely to be ACL but I'll ask for second opinion's on that please!
I'm inclined to suspect it's a bursa issue, the bursa's are fluid filled sacs that protect the knee and that may be why the joint feel tight there is also a bursa at the back of the knee.

Thanks so much for your reply,

That gives me some piece of mind, but I will definitely get a second opinion as soon as I can get an appointment with my physio.

I did forget to mention in my original message that I do experience some very minor pain when I kneel - or any combination of flexion and pressure to the joint (including outer thigh stretches). Is this in line with what you would expect for bursa issue?

Where is the pain when you do these things? At the front or the back of the knee?

It's quite difficult to pinpoint, but it seems be at the back and to the outside/lateral area of the knee (this can be reproduced when I sit with my leg crossed, i.e. when I sit upright on a chair and rest my left foot/ankle on my right knee). I feel no pain when I rub, press or massage the area.

In addition, I feel pain at the back of the knee if I try to do hamstring curls (lifting 23kg), so I stopped. However, it is not as noticeable using lighter weights, but I have ceased doing this exercise anyway.

Thanks.

You see now I'm starting to think it may be the popliteus muscle which is involved in unlocking the knee, ie bringing it from a straightened(extended) to a bent(flexed) knee position. The pain on hamstrings curls may bring this on, because you're essentially trying to resist this movement (ie the job of the popliteus) when you do this. You said that you feel no pain behind the knee normally, try sitting in that cross-legged position again and have a feel behind the knee, if it feels sore/tender behind the knee in that position it may well be the popliteus.

Thanks Sarah,

I've tried what you suggested and experienced no pain.

Since my last post I've completed a weights session, a kettle bell class, a cardio session (spin bike), and three brazilian jim jitsu sessions, and it has responded well each time. I guess it couldn't be that bad, if anything, it seems to be improving (slowly).

I do experience pain when I kneel, or when I extend my knee past my foot (moving forwards).

Any other ideas or advice would be appreciated, but if there's nothing else you can suggest I really appreciate your feedback - thanks.

The fact it's improving in such a short space of time would suggest to me it's likely to be more a soft tissue/inflammatory problem and it is settling down nicely. Kneeling is generally a position which aggravates knees regardless of the problem/injury as it puts a lot of pressure on the joint. If you're still managing to carry out such a high level of exercise/activity, I'd advise to continue as you are and just give it a bit more time to improve. :)

Furthermore, I'd add that if the pain worsens or does not settle, go and see a physio.