Lacerations to the leg and foot are commonly seen in the Emergency Department. The mechanism of injury determines the likelihood of disruption to underlying tissue, the risk of a retained foreign body, and the degree of potential contamination. See Chapter 9 for additional information about evaluating and preparing wounds for repair. As with other extremity injuries, evaluating limb positioning at the time of injury and replicating this during wound evaluation may help to uncover occult tendon injuries.
DIAGNOSIS AND DIFFERENTIAL
Assess lower extremity wounds for any associated nerve, vessel, or tendon injuries. Evaluate distal motor and sensory function and compare findings from the injured extremity to the contralateral side. Sensory function is best evaluated prior to providing anesthetic agents, but a full assessment of motor function and wound exploration may be easier to perform after the wound is anesthetized. Evaluate the superficial peroneal nerve (foot eversion), the deep peroneal nerve (foot inversion and ankle dorsiflexion), and the tibial nerve (ankle plantar flexion). Move the limb through its full range of motion to exclude tendon injury. Test each tendon function individually and visually inspect the wound at rest and in motion to rule out a partial laceration. Evaluate the extensor hallucis longus (great toe extension with ankle inversion), tibialis anterior (ankle dosiflexion and inversion), and achilles tendon (ankle plantar flexion and inversion).
Laboratory studies are not typically indicated for simple lacerations. Consider x-rays if there is suspicion for a fracture or radiopaque foreign body. Ultrasonography may also be useful to identify a foreign body, tendon injury, or bony abnormality.
EMERGENCY DEPARTMENT CARE AND DISPOSITION
See Chapter 9 for discussion of wound preparation. Thorough wound exploration and irrigation of lower extremity wounds are important.
Wounds on the lower extremities may be under greater tension than those on an upper limb. Consider performing a layered closure with 4-0 absorbable material to close the fascia and interrupted 4-0 nonabsorbable sutures to close the skin, when appropriate. This type of layered closure is not typically required for wounds on the foot.
When possible, avoid placement of absorbable deep sutures in patients with diabetes, immunocompromise, or venous stasis changes due to an increased risk of infection.
Determine each patient’s tetanus immunization status and update as necessary (see Chapter 94).
Cyanoacrylate glue is not used as often for wound repair on the lower extremities because of the greater wound tension associated with these injuries.
Once repaired, lacerations involving the joint or tendons should be splinted in a position of function.
Evidence does not support routine antibiotic prophylaxis in uncomplicated lacerations of the lower extremity. Antibiotics are recommended for open fractures, tendon or joint involvement, heavily contaminated wounds, bite wounds, patients with higher risks for infection, and wounds that exhibit early signs of infection.