I just began playing violin again after a 10-year break, and I am having problems with my 4th finger. When I place it on the violin, my knuckle collapses (the bottom one - on my hand) and then I have problems removing my finger from the string quickly and easily. Can you suggest any exercises, troubleshooting ideas, etc?

Hi. I have been playing for 3 yrs. Getting control over your 4thfinger is easy. you have to strengthen it. I recomend "pinky ups". a technique where u pull the pinky down and up. perhaps on a table. hope this works.