I’ve developed a lack of mobility and pain in my left wrist, that only became apparent when trying to perform push-ups. I am right-handed and have a desk job, and haven’t traumatized the wrist (to the best of my knowledge) to warrant a sudden issue. Would physio be able to diagnose or help correct my issue?

A physio will be able to determine what in your wrist is causing the decreased mobility. It could be tight muscles, swelling in one of the small joints of the wrist, a slightly displaced bone in your wrist (there are lots of small bones in your wrist), or a combination of the above. What happened to cause this problem may be more difficult, but very important, to figure out. The physio will try to work this out with you. It may be easier once the structures that are injured are known. It may be as simple as you having your wrist bent up while you are sleeping. Once the diagnosis is known treatment can be started if necessary to resolve the problem. Hope this helps.