Which muscle is being injected by botulin?

The technique for injecting botulinum toxin into the inferior lateral pterygoid muscle. Note that there is an electrode on the chin and a wire attached to the needle so that the electromyographic activity can be monitored at the needle tip. B, Once the needle is placed to the proper depth, the patient is asked to push against resistance provided by the operator. If the needle is properly placed in the inferior lateral pterygoid muscle, the electromyogram will increase on the monitor. Once the proper position has been verified, the botulinum toxin is injected.