A streetnail derives its name from the carriage horses of old, who spent their days pounding pavement on less than perfectly manicured roads.  Stray metal in the form of nails, screws, and wire littered the roads of the past, creating a treacherous surface for horses to work on.  Many a horse was rendered permanently unsound, if they even survived the incident.

A streetnail is not limited to metal objects alone.  Wood and plastic can easily be hard enough to penetrate the hoof.  The frog area is commonly affected due to its spongier composition.  Whatever the object is composed of, a foreign body in the foot is a serious situation.  While your gut may tell you to pull the nail, screw, or stick out of your horse’s foot, leaving in it may actually allow for your veterinarian to better determine its position in the foot, and if any important structures are affected. 

Radiographs are the first line of defense in working up and treating a streetnail.  Radiographs allow the veterinarian to determine where the object appears to be in the foot and in what proximity it is to critical structures such as the navicular and coffin bones, the coffin joint, the navicular bursa, and the deep digital flexor tendon and its sheath.  Objects that penetrate the foot but do not contact any of these critical structures may be treated more conservatively, pending the horse’s soundness, than those that do.  The digital flexor tendon sheath, the coffin joint, and the navicular bursa can be accessed via centesis to determine if communication between the wound and these synovial structures is present.  Surgery, to debride bony lesions and clean out infected pockets may be performed when objects appear to contact either the coffin bone or the navicular bone and it’s bursa.  Tenoscopy may be performed to flush out infected synovial fluid in the deep digital flexor tendon sheath and to debride any tendon lacerations.  Soundness for work has a guarded prognosis in these situations. 

In all cases, the object should be left in place if at all possible until the veterinarian has been able to take radiographs.  Following removal, all horses should be treated with broad-spectrum intravenous antibiotic therapy to combat infection, Bute or banamine to decrease inflammation and for pain relief, and boostered for Tetanus.  The wound should be flushed with sterile saline and antiseptic such as betadine and packed with antiseptic or antibiotic soaked gauze.  The horse should be kept quiet and the foot kept dry.  Soundness should be assessed daily, and is critical to assess in those horses who have confirmed or suspected synovial structure involvement.  The horse’s other feet should be monitored for soreness, heat, and increased digital pulses as laminitis can develop as a result of uneven weight bearing.  Streetnail is a potentially life-threatening injury that should be treated as such.