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What is it?
Basal Thumb Strain – also known as CMC osteoarthritis – is a condition that develops gradually over time. Pain at the base of the thumb is particularly common in post-menopausal women in the fifth to seventh decades of life. It is frequently located either at the palmar surface of the trapeziometa-carpal joint, or more dorsally, between the base of the first and second metacarpals.