Impingment/Tendonitis in Knees, Elbow and Shoulder - linked?

[campionissimo]

In the last 12 months I've suffered badly with Hoffa's syndrome in the right knee (pinched fat pad behind the knee cap), tendonitis in the right elbow, and a rotator cuff injury to the right shoulder.

Now, my left knee is really painful with tendonitis (just above the knee). I can't squat down without feeling like the knee is going to explode, nor can I drive comfortably. I was in agony after a 30 mile journey yesterday, and missed 3 gearchanges as I couldn't fully depress the clutch.

I'm 6ft tall, 15 stone (so a bit extra, but nowt ridiculous), haven't done any sport since October when I stopped playing tennis due to the rotator cuff. I stay at home and look after the kids, so always on the go, doing lots of walking etc......

Anyone any idea if all these muscle/tendon impingements could all be linked - It seems odd to be picking up so many similar injuries in such a short space of time?

Any thoughts appreciated.