Hi Susan,
Twitching would take place when the nerve is being compressed either by swelling of the nerve itself as would occur in an injury or compression on it by surrounding structures which could be muscle bone or any growth. Swelling can also occur in the surrounding structures in case of of injury.
The trembling of the limbs further suggests that the nerves suuplying these areas are under pressure which needs to be examined as well as the pressure should be relieved . Such a situation can also occur in imbalance of the certain minerals and neuropathies.
Right now your husband needs to medical care and I would suggest you to take him to ER as soon as possible.
