How can my recent “minor” injury to the base of my thumb cause me so much pain and difficulty with even the lightest activities?

The joint in the base of the thumb is called the trapeziometacarpal joint (TM). If the ligaments around this key joint are injured or stretched, the joint becomes loose and unstable. This causes the tissues in and around the joint to be strained during relatively simple activities. Talk with your doctor about treatments that can help ease pain.