Ulnar-Sided Digital Nerve Tumor of the Thumb in the Professional Baseball Player Who Uses Grip-Adjusting Batting Equipment: A Report of 2 Cases.

Neuropathy of the ulnar digital nerve of the thumb is a relatively rare clinical entity. We report 2 cases of ulnar-sided digital nerve tumors of the thumb in 2 professional baseball players who routinely used grip-adjusting batting equipment. Symptomatic relief was achieved with nonsurgical treatment that allowed both players to continue playing during critical times during their season. We postulate that there may be an association with the grip-adjusting batting equipment and the development of digital neuropathy.