Straddle injuries occur when the soft tissues of the vulva are compressed between an object and the underlying bones of the pelvis. This trauma may result in ecchymoses (bruises), abrasions, and lacerations (see Figs. 16-1A & B and 16-2A & B). Extravasation of blood into the loose areolar tissue in the labia, along the vagina, the mons, or clitoral area, may cause ecchymosis (see Fig. 16-4) and/or hematoma to form (see Fig. 16-5). Examples of commonplace accidental straddle injuries include falling onto the frame of a bicycle, playground equipment, or piece of furniture. Nonpenetrating injuries usually involve the mons, clitoris, and labia and result in linear lacerations,
ecchymoses, and abrasions, sparing the hymen and vagina (see Figs. 16-6 and 16-7). Lacerations may require repair under local anesthesia, conscious sedation, or general anesthesia.

Vulvar hematomas (often sustained as a result of a straddle injury) can be very painful and may prevent a child or adolescent from urinating because of pain and swelling (see Fig. 16-5). The patient can be managed conservatively with immediate application of ice packs and limitations on physical activities if these conditions are met: (a) the hematoma is not large or expanding, (b) the perineal anatomy is not distorted, and (c) the patient has no difficulty emptying her bladder. In patients who are unable to void, placement of a Foley catheter is appropriate; otherwise, urinary retention will result (see Fig. 16-8). As the hematoma resolves, the blood will track along the fascial planes. The ecchymotic discoloration may take weeks to resolve. Pressure from an expanding hematoma may cause necrosis of the skin overlying the hematoma and result in eschar formation and tissue sloughing (3). The hematoma may spontaneously rupture and require evacuation, cleaning, debridement, and closure (see Fig. 16-9A–E) (see also Treatment page 301).

Penetrating injuries occur if the victim falls upon a sharp or pointed object and impales herself. Examples of household objects associated with impalement include in-lawn sprinkling systems, pipes, fence posts, trailer hitches, and furniture. The vagina, urethra and bladder, anus, rectum, and peritoneal cavity can also be pierced by sharp or pointed objects. The physical findings may vary and can appear to be quite minimal, yet the patient may have a more serious underlying injury only appreciated with adequate exposure (see Fig. 16-10A–C). In a report of 34 perineal impalements, several patterns emerged. Most injuries occurred in the home. Many children either slipped or fell in the bathroom on bathtub toys, soap dispensers, or the shower diverter valves or fell onto objects when climbing out of the tub or when running out of the bathroom after bathing. Slippery surfaces and the lack of protective clothing were stated to be the common contributing factors. Bedroom accidents occurred when children were jumping from one bed to another, a common play activity with obvious risk. Infants and children should be supervised in the bathtub as they may be at risk for drowning and scalding injuries if the bath water is too hot. They are also at risk for trauma from falls onto objects, but even the presence of supervising adults did not completely prevent these accidents (4). Accidental penetrating injuries may closely mimic the injuries associated with sexual assault, so corroboration of the events by an eyewitness is very helpful.

Vaginal insufflation injuries occur when pressurized fluids enter the vagina. The walls may overdistend and tear, resulting in bleeding with significant blood loss. Such injuries may produce no sign of external genital trauma, and only careful vaginal examination (often under anesthesia) will reveal the source of bleeding and true extent of injury. This may occur accidently when girls fall while water skiing or riding jet skis, sliding down water chutes, and coming in direct contact with pool or spa jets. Children and women who participate in water sports can decrease their risk for vaginal insufflation injuries by using protective clothing such as neoprene wetsuits or cut-off jeans while water or jet skiing. When using a waterslide, head-first entries are usually forbidden to prevent head and neck injury, but it is also wise for girls to cross their ankles and/or to keep their feet together when entering water from a waterslide to prevent genital trauma (5,6,7).

Motor vehicle accidents are the most common mechanism of injury resulting in pelvic fractures for occupants, pedestrians, pedal cyclists, and motorcyclists. Shear forces can lead to lacerations when there is a fall associated with rapid abduction of the lower extremities or from the compressive forces associated with being run over by a motor vehicle. Vaginal lacerations with and without associated hymenal injuries have been reported (8,9). Falls or crush injuries during a collapse of a building due to structural problems or stresses from natural catastrophes (earthquakes), bombings, and warfare are the next leading cause of pelvic fractures that may lead to genitourinary injuries. Any time a pelvic fracture occurs, genital injuries may arise when fragments of the pelvic bone penetrate the vagina and lower urinary tract. This may lead to lacerations of the bladder, urethra, or vagina. The overall incidence of a genitourinary injury associated with a pelvic fracture was 3.62% in women (age not specified) in the National Trauma Data Bank. Predictors of bladder injury include widening of the symphysis pubis and sacroiliac joint. Fractures of the inferior and superior pubic rami and widening of the pubic symphysis were associated with urethral injuries (10).

Animal bites are rare but may be a cause of genital trauma. Most dog bites involve the extremities but in children more commonly involve the head and neck. Many dog bites are inflicted by the family pet or a neighbor’s animal. Human bites tend to occur in children as a result of playing or fighting, while in adults they are usually the result of aggressive behavior or participation in sports or during sexual activity. Mammalian bites may cause significant damage to delicate tissue of the genitalia. Microorganisms contained in saliva may cause infections resulting in local cellulitis or facilitate inoculation and transmission of communicable diseases. Genital bites are at high risk for infection because the loose subcutaneous tissue may facilitate bacterial spread (11,12,13).

Scalds are the leading cause of burn-related hospitalizations and emergency department visits for young children. Scalding due to hot tap water may be prevented by reducing the temperature settings in hot water tanks and testing the temperature of the water before placing a child in the bath. Recent awareness indicates that the bulk of scald injuries are non–tap water related and are associated with meal-time preparation of food (14,15,16).

Accidental immersion burns, where a child falls into a container of hot liquid, typically have irregular borders and nonuniform depth as the victim struggles to escape the hot liquid. This thrashing also causes splash marks, which, although they may sometimes be found in forced immersion, are more characteristic of accidental immersion. In accidental splash and spill burns, the head, neck, and trunk are commonly involved as the hot liquid is pulled or knocked over from a higher surface and spilled over by the child. Accidental contact burns are often patchy and superficial as the child quickly withdraws from the hot object or the falling object brushes across the skin.