It depends difficult to predict factors, such as:
How many parties have a legal and financial stake in your case;
Whether the at-fault parties dispute their liability or the damages you should receive;
The complexity of your case and the difficulty, if any, of obtaining evidence; and
Court schedules and other administrative considerations.
By and large, neither you nor your lawyer can do much to influence these factors. You can, however, consult an experienced catastrophic injury lawyer as soon as possible, which begins any claim you may pursue.