On the plus side, I can now use my PC again, with a lot of hard work from Bobby of You Me and IT. Recommended by a fellow dog park denizen, they're much cheaper than I'd feared, and excellent.
Had my hair buzzed this morning, and as usual, I look like a Bedlamite, but it feels great. It's also much easier to deal with than attempting proper shampoo and maintenance/ 'styling' in the shower every day with one arm in a feckin' bin liner. The new 'normal' cast and sling are considerable improvements over the horrible 'trauma sling',too. It was like an itchy lead-lined duvet.