Cubital Tunnel Syndrome, otherwise known as Ulnar Neuropothy, is much like it's more well known family member, Carpal Tunnel Syndrome, but effects a different area of the body, although close. CTS is caused by nerve pressure near the elbow, or funny bone area and causes tingling, muscle weakness and numbness in the hands and whole arms. You are at further risk of CTS and it's symptoms by leaning on or bending your elbow for long periods (for example, talking on a phone), sleeping on it or damaging connecting ligaments (athletes are most at risk here).
The first signs you are effected by Cubital Tunnel Syndrome are the aforementioned numbness and tingling anywhere in your arm and specifically in the ring fingers to smaller fingers. Worsened symptoms include loss of grip, hand muscle and developing a claw like deformity of the hand. A physical examination by a doctor and perhaps a more extensive test called electromyography can determine whether you have this condition and what it's being caused by.
To prevent worsening of the condition it's important to employ some form of treatment so you don't experience the more severe symptoms. Your best treatment options will be directly related to the cause of it. If you bend the elbow while sleeping or a lot during the day (perhaps for work), you may want to use a splint that prevents over-use and bending of the elbow. You can also use a protective sleeve over the elbow to keep it warm and it's user conscious of proper use and form. Both these options are ideal for treatment, especially if Ulnar pressure is not detected by the electromyography test. If Ulnar pressure is detected and symptoms are severe, surgery maybe recommended. Although it's results are not immediate, surgery can return finger, hand and arm strength and over a longer period of time, reduce the tingling and numb sensations.