Lumbrical Tear in Major League Baseball Player Throwing 4-Seam Fastballs: A Case Report.

Proposed injury was secondary to the 4-seam fastball technique, which pulls apart the FDP of the second and third digit, as well as the FDP of third and fourth digit. This increases the distance between the origins of the second and third lumbricals, leading to strain and tearing. The increased pitch count of the player also may have contributed to the injury. After rest and gradual tossing program, the pitcher was able to return to a preinjury level of function at 6 weeks. One year out from injury, the patient continued to pitch and remained pain free.