Basal Thumb Arthritis, or arthritis at the base of the thumb, can be very disabling. Because the strength and motion of the thumb is required for nearly every activity - whether writing, opening a jar, or buttoning a shirt - pain from this condition may impede the most basic everyday tasks.
Like other forms of osteoarthritis, basal thumb arthritis develops when cartilage on the surfaces of the bones that meet at the joint wears away and the metacarpal bone begins to slip out of the joint. This loss of alignment often creates the appearance of a bump near the wrist. For reasons that remain unclear, the degree of inflammation and associated pain can fluctuate.
Arthritis in this location generally begins in patients from 40-50 years old, often with the x-ray appearance in advance of the symptoms.