It's ironic because if he was an employee, this kind of injury might be covered and surgery paid for by Workers Comp Insurance.
For example, when I worked as a Controller for a Food and Beverage Wholesaler, two of my office employee's had Carpal Tunnel
and the surgery and time loss was covered by our Worker's Compensation Insurance.
Obviously they used their hands for many personal activities
Following up on Lee's reasoning, if he has an HSA insurance plan, it becomes tax free if he uses HSA funds to pay for the medical costs not covered by his insurance. It isn't a business deduction, but tax free is still a good result.
Tom
Longview, TX