Cephalohematomas are common, and in the study from Nova Scotia shown in Table 33-3, these accounted for 80 percent of traumatic injuries with an incidence of 16 per 1000 (Baskett, 2007). They rarely develop in the absence of birth trauma, and an II-percent incidence was reported in 913 term
Diseases and Injuries of the Term Newborn 629 newborns delivered by vacuum extraction (Simonson, 2007). In the Network study of cesarean delivery outcomes cited above, the incidence of cephalohematoma was 2.4 per 1000 operations (Alexander, 2006). Others have reported lower incidences, although cephalohematoma is more common with vacuum compared with forceps deliveries-0.8 versus 2.7 per 1000 operative deliveries (Werner, 2011).
Subgaleal hemorrhage results from laceration of one of the emissary veins, with bleeding between the galea aponeurotica and the skull periosteum (Shah, 2016). Although most common with operative deliveries, cases with spontaneous vaginal delivery have been described (Uu, 2017). Because of its loose areolar tissue and large surface area, significant blood volumes can collect in this potential space and can extend from the neck to the orbits and laterally to the temporal fascia above the ears (Modanlou, 2016). Resulting hypotension can lead to signiicant morbidity, and cited mortality rates range from 12 to 18 percent (Chang, 2007; Kilani, 2006).
These are rare but are especially worrisome because of their association with the serious intracranial hemorrhages. Volpe (1995) considers three types of skull injuries to be fractures-linear and depressed fractures and occipital osteodiastasis. In a French study of nearly 2 million deliveries from 1990 to 2000, the incidence of skull fractures was reported to be 3.7 per 100,000 births, and 75 percent were associated with instrumented vaginal deliveries (Dupuis, 2005). These are occasionally seen with spontaneous or cesarean delivery (Fig. 33-3). These latter fractures are more common when the head is tightly wedged in the pelvis. In such cases, there are at least three possible causes. A fracture may result from skull compression against the sacral promontory, by hand pressure used to lift the head at cesarean delivery, or from transvaginally applied upward hand pressure by an assistant. Fractures are managed with surgical decompression, although spontaneous resolution can follow (Basaldella, 2011).
FIGURE 33-3 Depressed skull fracture evident immediately after cesarean delivery. Labor had progressed, and the head was deep in the pelvis. Dislodgment of the head from the birth canal was performed by an assistant using manual pressure upward through the vagina. (Used with permission from Dr. Kimberly M Spoonts.)
Overstretching of the spinal cord and associated hemorrhage and edema are rare. They are usually caused by excessive longitudinal or lateral traction of the spine or by torsion during delivery. In some cases, vertebrae are fractured or dislocated. Menticoglou and associates (1995) described 15 neonates with this type of high cervical spinal cord injury and found that all of the injuries were associated with forceps rotations. Spinal cord injury also can occur during breech delivery. Ross and coworkers (2006) described C5-6 vertebral dislocation associated with a Zavanelli maneuver done because of shoulder dystocia (Chap. 27, p. 523).
Traumatic injuries to nerves can be serious and distressing, especially if permanent. Injury can involve a single nerve, or it can afect a nerve root, plexus, or trunk (Volpe, 1995).