I pulled my shoulder the other day... was wondering how I could have done it. The answer was, while digging a few targets in semi hardened ground with my hand digger, the wooden handle that was already gaffa taped because it was busting out a little near the buisiness end gave way and became semi useless.... not to be detered I pushed on, just holding the digger in a choke hold to still be able to retrieve the junky miserable targets. This of course had an effect on my shoulder as the fulcrum had changed an unawares as I was damaged the shoulder muscle as I had to increase the muscle power to effect the same usual dig.... almost back to normal now, but was a real pain at first.... couldn't even do the washing up as much as I'd have liked too