Q: I play darts and snooker and sometimes I struggle to release the dart and I move as I deliver the cue to the ball. What can I do to improve my hand-eye co-ordination?

A: I don’t think your hand-eye co-ordination is at fault. You appear to have the darts and snooker equivalent of the golfer’s ‘yips’. That’s caused by holding the club, cue or dart too tightly, so that the muscles in your hands and wrists are too tense. Train yourself to hold the dart and cue more lightly, and you should be able to deliver both much more smoothly. Tension in your hand and forearm muscles is almost certainly the cause of your problem.

Q: I get muscular spasms in my neck that cause a sudden involuntary movement. Muscle relaxant tablets don’t help. Can you advise?

A: It sounds as if you may have a mild form of ‘dystonia’, which can range from a twitching eyelid or symptoms like your own to a wry neck or full body spasms. Your doctor may put you in touch with your local branch of the Dystonia Society, which helps sufferers. This is one good medical use of injections of botulinum toxin, which can stop the spasms. You may be offered them.

Q: I have been having vitamin B12 injections for pernicious anaemia for 20 years. For about a year now I’ve had numbness and pins and needles in my fingers and toes. Could this be caused by the injections?

A: Far from causing the symptoms, the vitamin B12 should be keeping symptoms like this at bay. Pernicious anaemia, and a similar disease, folate deficiency anaemia, can cause nerve problems that fit these symptoms exactly. You may need a higher dose of vitamin B12 or folic acid, or the symptoms may be due to something other than your anaemia. Do see your doctor, who will probably want to take things further.