We managed thirty-three patients who had open injuries of the foot related to the use of a lawn mower from 1985 through 1992. Twenty-eight of the patients were male and five were female. They ranged in age from four to seventy-three years old. The injuries were associated with the use of push lawn mowers (twenty-two patients), riding lawn mowers (nine patients), and self-propelled lawn mowers (two patients). The injuries included forty open fractures, twenty amputations, eighteen lacerations of the skin and nail beds, nine lacerations of tendons, two closed fractures, segmental loss of bone in two patients, and segmental loss of the Achilles tendon in one patient. The findings on culture of intraoperative specimens revealed a mean of 3.1 organisms (range, one to nine organisms) per patient. All of the patients were managed with at least one operative procedure (mean, 2.4 operations; range, one to five operations), and all were treated with parenteral antibiotic therapy (mean, 2.3 antibiotics; range, one to six antibiotics) except for one patient who had oral antibiotic therapy. The mechanism of injury was documented for twenty of the twenty-two patients who had been injured by a push lawn mower. Seventeen patients were injured while pulling the push lawn mower backward, and eight of those patients had been pulling the lawn mower up a slope.(ABSTRACT TRUNCATED AT 250 WORDS)