I'm 44 and for a few years now have been having a very intermittent problem with my left shoulder where it seems to partly dislocate then pop back in again (I believe this is called a subluxation). It can be incredibly painful and if it's a bad occurrence the shoulder and even the arm can be painful for at least a few hours, maybe even days.

Unfortunately the time that it usually happens is when I'm asleep and lying on my left side - I can wake up shouting with the pain and shock of it. This used to only happen once every few months, but lately it's been happening about once a week. If I can avoid lying on my left side (tricky when you're asleep!) then it's okay. I say it happens when I'm asleep, but sometimes during day to day activities if I twist or stretch my arm awkwardly it will also occur. Lifting a heavy object above my head can also cause this seemingly partial dislocation of the shoulder joint.

I must admit that I'm not a fit person (I'm not overweight though) - I get about zero exercise and my work involves the repair of circuit boards, so very few muscles get exercised from that!

Is there anything that I can do to minimise the problem? Avoiding sleeping on my left side seems like a good idea, but that seems difficult to put into practice!

Would it be worth strapping up my left arm in some form when I go to bed to avoid it moving into a position that will perhaps cause the problem?

I should say that I'm right handed and have no problems at all with my right shoulder (perhaps because the muscles are slightly better developed?).