You can try the direct drive mode if you are playing VMD motion on PMX models. This is in the "Motion Settings" in the actor menu.
Also you can find in the "Troubleshooting" settings there are options to do "Twist correction", this can reduce twisting of the arms. This depends on the motion and the actor so there is no one-size-fit-all solution. You just need to try these settings and find the best configuration that works for the model and the motion you selected.