It is totally preventable if caught early enough, and even once it's semi-advanced can be managed and even reduced.
Surgery is only required in the worst cases.
The fingers are controlled by muscles in the forearm.
These forearm muscles turn into tendon that then cross the wrist joint and connect to the end of the finger.
As the trigger finger dynamic advances, the tendon enlarges (usually at a single finger joint) and then bone grows up in the area.
Trigger finger symptoms first look like stiffness in the finger(s).
Then when bending and/or straightening the affected finger, the motion starts to 'catch' or 'stick'.
Meaning, the other fingers will keep moving, but the affected finger won't move, stuck, until it suddenly lets go (sometimes with an audible pop or crack noise).
This not only looks kind of creepy, but it is frightening to the affected person because they can see the trend of less and less 'correct' movement of their finger, and it consistently gets worse.
We take our healthy bodies for granted until they begin to not work so well..
Trigger finger is a form of tendonitis and develops for one of both of two reasons: Repetitive Motion, and/or nutritional issues.
Trigger finger often shows up with arthritis, and/or with diabetes, both of which are the long term results of nutritional deficiency (and lack of exercise, and other basic requirements for a healthily functioning body).
The tendon is inflamed, it gets swollen, and then it hardens.
And just like all tendonitis, the actual problem is originally and continually caused by muscles that are too tight, connective tissue that is too tight and restrictive, a process of inflammation, nutritional deficiency, etc.
No amount of rest can ever fix trigger problem in a finger.
To reduce the side effects of trigger finger, you must decrease each of the above factors.
As long as they are in place, the tendon at the affected knuckle will continue to get larger, harder, etc, and the tissue around it will also continue to grow and harden.
The body works best when soft, healthy, and supple.
Anybody suffering from trigger finger would be well advised to do something effective as soon as possible.
The worse trigger digit gets, the harder it is to stop it's progression and to remove the side effects.
For instance, once bone grows up towards or around the tendon, there's no getting rid of it or making it smaller (aside from trigger finger surgery, which causes it's own damage and problem).
Likewise, once a tendon increases size and hardens, it takes A LOT of work to make it soft and supple.
The moral of the story is, start effective self care for trigger finger as soon as it is noticed.
The longer it's ignored or avoided, the harder it is to make it better.
Understand how trigger finger works so you can stop it in it's tracks.