Question: My girlfriend tells me that while i'm sleep, I occasionally start to jerk, sometimes violently. It is to the point that she is scared to sleep next to me because she has gotten injured in the past.

I never realize these movements, but it does cause me to wake up frequently cause poor sleep and extreme fatigue throughout the day.

She describes these jerking motions usually starting with a lim (leg or arm) that will quickly push outward and inward multiple times then spreading to other lims. My torso will also jerk forward and back really fast and even neck.
She describes that the episodes last for only a few seconds multiple times through the night and says that I usually awaken right after.

Again, I am unaware of these movements but they are apparently making it impossible for me to sleep well, and making it impossible for my girlfriend to sleep next to me.

Im not sure when this started but it developed at lease 2 years ago and seems to be getting worse. Im also unable to function during the day due to the exhaustion.

What could cause this issue. Should I be concerned? Are there any solutions?