Violin Bow Hold- Thumb cramping- WhY? How can I fix it?

Question:So, I've been playing for 14 years. i started playing when I was 4-years-old. I've never had this problem until about a month ago. I think it might be over practicing or too much tension...cause I had a chamber soiree (quartet performance) a few weeks ago, recital yesterday, and a compeition tomorrow.
Yesterday, my recital went like crap because I physically couldn't play through my whole piece without my thumb hurting. and now it's my worst fear. I'm playing Praeludium & Allegro by Kreisler, which is a song that needs a lot of bow control.
I don't know how to fix it...

Best Answer - Chosen by Asker: So, I've been playing for 14 years. i started playing when I was 4-years-old. I've never had this problem until about a month ago. I think it might be over practicing or too much tension...cause I had a chamber soiree (quartet performance) a few weeks ago, recital yesterday, and a compeition tomorrow.
Yesterday, my recital went like crap because I physically couldn't play through my whole piece without my thumb hurting. and now it's my worst fear. I'm playing Praeludium & Allegro by Kreisler, which is a song that needs a lot of bow control.
I don't know how to fix it...

My first reaction is to tell you to relax. Cramping is usually caused by tightening your muscles and holding them for too long. If your bow is not loose and relaxed, you will not get the best out of it anyway.

Ask your teacher to look at your bow hold, and if your teacher is not also your director, ask your director as well. Go back to the basics and play some long full bows with a conscious effort to relax and relieve the pressure on your thumb. You could be suffering from improper bow hold or you might be unconsciously sticking your thumb through the gap instead of using the ferrule (the silver part) to help stabilize it. You may not be using your first finger properly and putting too much pressure on the thumb to stabilize thee bow. You may also be letting your first and second finger slip from the frog, which would also put too much pressure on your thumb. This is why a good partnership with a teacher or mentor is critical at every stage of your development.

There is also a slim chance that you may have a neuromuscular condition which can only be diagnosed by a physician. This is rare and your teacher can advise you if there is any chance at all. This may have nothing to do with your bowing, could be a result of something like carpal tunnel syndrome from typing or other repetitive stress injury, but it would be wise to get it diagnosed and treated as soon as possible to avoid permanent injury. I sincerely hope you get this under control as soon as possible and hope that this helps you identify and overcome it, even if the only useful advice I can offer is to seek professional help.

You need to back away from practicing for a while; your thumb is strained. When some part of the body is hurts -- quit doing that~~