Management of lawn mower injuries to the foot and ankle

Seventy consecutive patients treated for lawn mower injuries to the foot and ankle were reviewed to determine optimal treatment, functional results, and complications. Injuries were classified into 1 or more functional-anatomical zones (I, digits; II, dorsum; III, plantar nonweight-bearing surface; IV, heel; and V, ankle) for a total of 96 injuries. Thirty-one patients were available for follow-up. Mean age was 36.7 years and 84% were males. Most injuries (67%) involved patients > 16 years old using a push mower; however, 18% involved children < 5 years old, usually caused by riding mowers (70%). Primary closure after adequate irrigation and debridement was the preferred method of treatment except in patients with Zone IV injuries. Antibiotic prophylaxis was used in almost all injuries (93%). A 100% ambulation rate was achieved with 10% of patients requiring a prosthesis. Zone IV (heel) injuries had a 50% complication rate from chronic soft tissue breakdown. The wound infection rate per injury was 12.5% and did not vary significantly between closed (11.4%) and open (17.6%) treatment. Lawn mower injuries to the foot and ankle can be closed primarily after adequate irrigation and debridement without compromise of infection rate or function. Antibiotic prophylaxis is recommended. One-sixth of these injuries involve children < 5 years of age and can be prevented.