Birth injuries are an uncommon complication of vaginal and cesarean delivery. Injuries range from those that are minor and require no further diagnostic evaluation or treatment to those that are life threatening or associated with long-term morbidity. Risk factors for injury include macrosomia, precipitous or prolonged delivery, breech presentation, cephalopelvic disproportion, shoulder dystocia, and the use of forceps or vacuum to assist extraction. However, birth injuries also occur in infants with no identifiable risk factors, making prediction difficult.
Fractures as complications of the delivery process most commonly occur in the clavicle, humerus, and femur. Skull fractures are also reported, usually in association with forceps delivery. Long bone fractures generally require evaluation by an orthopedic specialist, whereas skull fractures are usually simple linear fractures that do not require intervention. Infants rarely have more than one fracture; for those with multiple fractures, diagnoses such as osteogenesis imperfecta should be considered.
Clavicle fractures occur as a complication of the delivery process in approximately 0.5%1 to 1.7%2 of all live births. Historically, clavicle fractures were thought to be a result of obstetric mismanagement. Recent studies, however, have shown that little can be done to prevent this complication. Clavicle fractures are most commonly reported with vaginal deliveries, but they are also reported with cesarean sections. Risk factors include fetal macrosomia, instrumented delivery, and a prolonged second stage of labor, but predictive models based on these factors have a high false-positive rate and have not been clinically useful.
The humerus is occasionally fractured during the delivery process, typically with a difficult vertex delivery of the shoulder or a breech delivery. The fracture may result from direct pressure or traction. A greenstick fracture is most common, but displaced fractures may also occur. Breech deliveries may also result in a femur fracture; most are complete fractures that result in obvious deformity.
Clavicular fractures are sometimes overlooked, particularly in the case of a nondisplaced fracture. Acutely, the examiner may feel crepitus, and irritability may be noted with pressure over the bone. In displaced fractures, a bony ledge may be palpated. The infant may have decreased movement of the ipsilateral arm with an asymmetric Moro response. This pseudoparalysis is typically related to pain but may also be the result of associated nerve damage. Frequently, the fracture is first diagnosed as normal healing occurs and the callus forms, which may be noted as early as the second week of life.
Humerus fractures may present clinically with swelling and pain; in the case of a displaced fracture an obvious deformity will be noted. The infant may refuse to move the affected arm, thereby resulting in an asymmetric Moro reflex and pseudoparalysis; however, nerve involvement may also occur. Most femur fractures will present as an obvious deformity.
The diagnosis of neonatal clavicle fracture may be made clinically either at the time of delivery or in the first month of life. A single anteroposterior radiograph of the chest is sufficient to confirm the fracture if the diagnosis is in question. Plain films are also usually sufficient to confirm the diagnosis of humerus or femur fractures.
Clavicular fractures usually heal without sequelae or deformity. Management is conservative and involves keeping the infant off the affected side; immobilization of the arm may help decrease pain. Healing should occur within 2 weeks, and callus formation may be seen radiographically in several weeks. Parents may complain of a bony irregularity as the clavicle heals, but it will become less prominent as the child grows.
Treatment of humerus fractures is generally limited to immobilization for 2 to 4 weeks in the adducted position, and the prognosis is excellent. Treatment of femur fractures is 3 to 4 weeks of traction and suspension of both lower extremities. Immobilization with a Pavlik harness may also be effective in treating femur fractures. The prognosis is excellent.
Admission to the neonatal intensive care unit for management and consultation with a pediatric orthopedic surgeon is indicated for infants with concerns for humerus or femur fracture, including focal pain, edema, erythema, or deformity. Infants with clavicular fracture can generally be managed on the routine postnatal ward. Discharge criteria include adequate pain control and nutritional intake as well as timely access to primary care and orthopedics follow-up if indicated.
Nerve damage is an infrequent, but important complication of the birthing process. In some cases, injury may be traced to traction on the neck and thus on the brachial plexus during delivery. Severity can range from mild stretching of the nerve, to nerve root avulsion. Brachial plexus injury is documented in 0.038% to 0.2% of all live births.3,4 A large retrospective analysis from the United States concluded that the risk of brachial plexus injury was 1 in 1000 live vaginal births.5 Incidence rates rise with birth weight; in one study of infants weighing more than 4500 g and born vaginally, the incidence of brachial plexus injury was 3.6%.6 Risk factors include macrosomia, shoulder dystocia, breech presentation, and instrumented delivery. However, because many cases of brachial plexus injury occur without these risk factors, an effective predictive model has not been established.
Injury to the fifth and sixth cervical (C5 and C6) nerve roots is the most common nerve injury (Figure 125-1) and results in partial paralysis of the upper extremity, known as Erb-Duchenne paralysis. Affected infants have unilateral arm weakness and an asymmetric Moro response. The hypotonic extremity is adducted, internally rotated, and pronated at the forearm. Additional involvement of the seventh cervical (C7) root results in paralysis of the wrist and finger extensors, which causes unopposed flexion of the hand. Together, this is described as the “waiter’s tip” position (Figure 125-2).
Klumpke paralysis is very rare and involves isolated injury to the seventh and eighth cervical (C8) and first thoracic (Tl) nerve roots. These infants have normal shoulder and elbow position but a weak or paralyzed hand. If the sympathetic fibers of Tl are also affected, miosis, ptosis, anhidrosis, and enophthalmos (Horner syndrome) are additional findings.
Infants may also have injury to the third and fourth cervical nerve roots (C3 and C4), which results in unilateral diaphragmatic paralysis from phrenic nerve involvement. These infants may present with respiratory distress, hypoxia, asymmetric chest wall movement, and diminished breath sounds on the affected side.
Total plexus injury (C5-T1) accounts for approximately 20% of all plexus injuries and results in a flaccid upper extremity. Involvement of C4 with or without C3 may accompany this severe form of plexus injury.
The differential diagnosis includes a clavicular or humeral fracture that may cause the infant pain and result in a pseudoparalysis that is not associated with nerve root damage. Pseudoparalysis of Parrot involving the upper extremity caused by a painful osteochondritis secondary to congenital syphilis can also mimic a brachial plexus injury. However, in this condition multiple long bones are generally involved and other features of congenital syphilis are often present.
The diagnosis of nerve root injury is usually made clinically and based on the finding of an upper extremity with abnormal tone and movement. Plain radiography can rule out an associated fracture of the clavicle or humerus. Electromyography and nerve conduction studies may help clarify the injury in anticipation of surgical repair, but they are rarely necessary otherwise. These studies are typically performed several weeks after birth. When required, magnetic resonance imaging (MRI) can define the anatomy and extent of injury.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
