As this case study illustrates, proper treatment, case management, and outpatient therapy can mean the difference between recovery and tragedy.
James, an active 3-year-old, was playing in the yard while his grandfather cut the grass. Unfortunately, Grandpa accidentally backed the riding mower into James, causing a significant injury to the boy’s left foot.
FIGURE 1. Preoperative x-rays revealed extensive bone and soft tissue loss
James’ medical history was unremarkable. He had had the usual childhood illnesses and was up to date on his immunizations. There was no history of surgery or hospitalizations. His parents said it was normal for him to play in the yard while his father or grandfather cut the grass. On the day of the injury, James was taken to a rural hospital for stabilization and initial evaluation of his injuries. He was then flown to our hospital for definitive treatment.
Preoperative x-rays (Figure 1) revealed a loss of the calcaneal tuberosity with obvious soft-tissue injury. The forefoot was intact, and he could flex and extend his toes freely. Sensation was difficult to assess, but James said he could feel stroking on the top of his foot. A comprehensive exam was performed once the patient was in the operating room, adequately anesthetized, and properly prepped and draped.
Multiple cuts were visible on the heel pad, approximately 75% of which was only minimally attached and considered questionably viable. Antibiotics were administered prior to the initial surgery. On inspection, grass and dirt were noted in the wound, which was copiously irrigated with pulsatile lavage. After extensive debridement, intact tendons were noted. The Achilles tendon, however, had been torn from the calcaneal tuberosity. The neurovascular bundle was also intact, but the subtalar joint was open in the back.
The mower blade had caused extensive bone and soft-tissue loss to the left calcaneus. This raised obvious cosmetic concerns, but more important, the injury to the Achilles tendon could result in toe-walking and difficulty with ambulation, running, and sports participation. James was also at risk for developing an infection in the heel and foot area, which could lead to sepsis if not detected early and treated effectively.
The surgeon tacked the Achilles tendon remnant to the remaining calcaneal tuberosity down through the plantar fascia and lightly tacked the heel pad down with loose nylon sutures. A vacuum-assisted closure (VAC) dressing was applied. This process involves placing a foam sponge into the wound, sealing the site with an adhesive drape, and applying negative pressure to remove debris, eliminate interstitial fluid, and promote granulation.
The patient’s foot was positioned in full equinus, and a posterior splint was applied over the dressing. He was started on scheduled antibiotics and admitted for postoperative care.
FIGURE 2. One half of the heel was nonviable
James was taken back to the OR 48 hours after the initial surgery, which is standard procedure with open (especially dirty) wounds. When the VAC dressing was removed, approximately one half of the heel pad was found to be nonviable. Even with a flap placed over the area, a small defect was present in the posterior heel. Slight debridement was performed, and the periosteum over the remaining calcaneal tuberosity was repaired with suture. The medial and lateral sutures from the previous surgery were left intact (Figure 2), and the VAC was reapplied (Figure 3).
FIGURE 3. A vacuum-assisted closure dressing removes debris
Two days later, James returned to the OR for the final surgical debridement and examination under anesthesia. Thankfully, the remaining tissue was viable, and there was no sign of infection. After an additional 48 hours of IV antibiotics, James was discharged home with a portable vacuum device, a peripheral indwelling central catheter line for IV sedation, and one month of oral antibiotics.
James returned to the pediatric ICU for twice-weekly VAC dressing changes under conscious sedation. Conscious sedation allows the wound to be inspected closely, cleansed, and debrided if needed.
This therapy continued for almost eight weeks. The wound healed without infection (Figure 4), and James suffered minimal discomfort. Once the wound was almost completely healed and the VAC was no longer necessary, a silver-containing carboxymethylcellulose dressing (Aquacel AG) was applied to the open area and changed in the office weekly. This type of dressing absorbs and interacts with wound exudate to form a soft, hydrophilic, gas-permeable gel that traps bacteria and conforms to the contours of the wound while providing a micro-environment that is believed to facilitate healing.
FIGURE 4. After therapy, the wound healed without infection
Aggressive physical therapy was initiated. In one to two years, James will need surgery to lengthen his Achilles tendon. Fortunately, he should have a positive outcome and return to normal activities without limitations. This is not true of many other children suffering similar injuries.
Every year in the United States, approximately 9,400 children younger than 18 (total number of children and adults 68,000) receive emergency care for lawn-mower-related injuries. While most victims are older children and adolescents, about 25% of these injuries occur in children younger than 5 years old. Males are the victim in 75% of these incidents. Riding mowers account for 21% of injuries, and other power mowers account for 23%. More than 7% of pediatric mower-related injuries require hospitalization, which is about twice the hospitalization rate for consumer-product-related injuries overall. Amputations and avulsions are necessary in 7% of pediatric mower-related injuries.1
This year, Children’s Hospital in Columbus, Ohio, treated 11 lawn-mower-related injuries (this did not include tractors or other farm equipment). Patients ranged in age from 18 months to 14 years. Most children younger than 5 sustained their injuries after falling off the mower while riding alongside an adult. Some were inadvertently run over while playing in the yard. While each child’s injury was different, every one was completely preventable.
When assessing a patient injured by a lawn mower, be sure to conduct an intact neurovascular and musculoskeletal exam. Once the status of these systems has been established, make sure the patient is comfortable about moving forward with treatment, whether it involves irrigation, suturing, or a simple dressing. Next, establish immunization status. If a patient with an open wound cannot remember or primary-care staff cannot determine the date of his last tetanus-diphtheria (Td) shot, an updated Td needs to be given.
Determining the nature of the environment at the site of the incident will facilitate antibiotic selection and prophylaxis. A broad-spectrum cephalosporin, such as cephalexin (Keflex), is appropriate prophylaxis in most instances, unless there is barnyard contamination. Most patients will have injuries that are more extensive and need tertiary-care treatment with two or more antibiotics.
Traditional wound care is appropriate for lawn-mower injuries. If the decision is to close a wound, copious irrigation and cleansing must be performed prior to suturing and followed with at least one week of appropriate antibiotics. If the wound is macerated and cannot be sutured, the severely injured skin should be debrided under local anesthesia before dressings are applied. A nonstick dressing is the bandage of choice, with once- or twice-daily cleaning using mild soap and water. Once the wound starts to granulate, a dry sterile dressing may be applied until the wound can be left open.
Topical antibiotics, such as bacitracin/neomycin/polymyxin B (Neosporin) or sulfadiazine (Silvadene) cream, can be applied at the clinician’s discretion. Each injury will be different and should be treated individually.
How these injuries happen
In addition to falling off a riding mower while seated alongside an adult, children can fall or slip into the moving blades of any lawn mower while playing nearby. Injuries can also occur when the mower is operated by children who are too young or immature. Rocks, metal, and other debris can be thrown by the mower and strike a child, frequently in the eyes or head. Burns can also be sustained by touching the mower while it is running or soon after it is turned off.
Lawn-mower injuries can be physically life-altering for the patient and emotionally wrenching for everyone involved.3, 4 Education, caution, and common sense need to be emphasized with every parent and caregiver regarding the proper use of riding and power mowers. Some lawn-mower injuries can be treated by a primary-care practitioner, but serious cases should be referred to the emergency department. Immunization status needs to be addressed, wound care administered, and prophylactic antibiotics given depending on the environment. If the patient has sustained a major injury, psychological counseling (for the patient and family) should be strongly encouraged and started as soon as possible. Finally, the wound VAC device allows these injuries to heal more evenly, cleanly, and quickly. We have used this device on every lawn-mower wound we have treated, with excellent results.
Ms. Horn is a nurse practitioner with the orthopedic service at Columbus Children’s Hospital, in Ohio. Ms. Ruth is a pediatric nurse at Columbus Children’s Hospital, with special training in wound and skin care.
1. Bull MJ, Agran P, Gardner HG, et al. Lawn mower-related injuries to children. Pediatrics. 2001;107:1480-1481.
2. American Academy of Pediatrics. Lawn Mower Safety. Available at www.aap.org/family/tipplawn.htm. Accessed May 17, 2007.
3. American Orthopaedic Foot & Ankle Society. Preventing Lawn Mower Injuries. Available at www.aofas.org/i4a/pages/index.cfm?pageid=3683. Accessed May 17, 2007.
4. Trautwein LC, Smith DG, Rivara FP. Pediatric amputation injuries: etiology, cost, and outcome. J Trauma. 1996;41:831-838.