Can you surgically remove knots on fingers caused from osteoarthritis?

Yes it is possible: Those knots caled hebreden node and could be removed if they bother.

Arthritic joints: Arthritis in some form is a common cause. The bumps on the distal joints near the nails are called hebreden's nodes and the ones near the pip or middle joints, bouchard's nodes. The bumps cannot generally be removed , they are part of the joint or small bone spurs and removal is ineffective and should nver be done for cosmesis alone or with the notion that it will alter the arthritic process