**5. Early management**

### **5.1. Immobilization**

**2. Incidence**

82 Treatment of Brachial Plexus Injuries

**3. Etiology**

macrosomia [9].

**4. Natural history**

Incidence varies from region to region and depends on the obstetrical care available in the region. The incidence of 0.42 per 1000 live births (1 in 2300) was reported in United Kingdom and Republic of Ireland [2]. Incidence is estimated to be between 1.6 and 2.6 per 1000 births [3].

Shoulder dystocia is the most common cause of BPBP. The neck on the side of the anterior shoulder is stretched, and this stretch injures the brachial plexus on that side, causing a varying degree of injury. The right side is more affected as the left occipito anterior (LAO) is the most common presentation during delivery. In one study incorporating 305 infants, the author reported that 60% of patients were affected on the right side and 37% on the left side [4]. The incidence of LAO position is almost 90%, and it does not explain a higher occurrence of the left side involvement, and therefore other mechanisms like intrauterine injury to plexus is also thought of. In one study, it was observed that almost half the cases they reviewed had not shoulder dystocia, and authors concluded that it could be caused by intrauterine maladaptation and not birth trauma [5]. Another hypothesis is that the posterior shoulder can get stuck on the sacral promontory and cause injury through a stretch while the baby is in the early stage of labor before shoulder dystocia takes place [5]. There is some electrophysiological evidence to suggest that BPBP could have occurred in the intrauterine period because denervation potentials are seen in EMG performed on day 1 after delivery. This is not possible if it has occurred at the moment of delivery [6]. Interestingly, BPBP is also seen following cesarean sections [7]. Bicornuate uterus is thought to cause BPBP with phrenic palsy [8].

Macrosomia has been defined as birth weight greater than 4000–4500 g. The Royal College of Obstetricians and Gynecologists reported that BPBP is a major complication associated with

Two strategies are attempted to reduce the incidence of BPBP. The first is to consider for cesarean section when fetus is macrosomic and the second is to train obstetricians regarding the effective management of shoulder dystocia. A study to compare the incidence of BPBP from 1994 to 1998 and from 2004 to 2008 did not observe significant differences in the incidence [10], although the cesarean section rate had increased from 10.7 to 18.4%. The authors of this study concluded that despite training in the management of shoulder dystocia and a rising institutional cesarean section rate, the incidence of BPBP has remained unchanged compared with 10 years earlier.

Most cases of OBPI are transient and have full recovery spontaneously. However, 10 [11]–27% [12] of children have incomplete recovery. They have lifelong functional impairment due to

muscle weakness, muscle imbalance, muscle contracture, bone and joint deformities.

The absolute immobilization of extremity is not advised except the child has associated clavicle or humerus fracture. Limb can be immobilized in a simple sling or a Velpeau sling for extremity fracture for a period of 2 weeks. Few mothers like to apply a pin between forearm sleeve and shirt to prevent the flaccid limb to fall on a side or get compressed while feeding the baby.

#### **5.2. Passive range of motion exercises**

Passive range of motion exercises should be started immediately to prevent the development of contractures at shoulder, elbow and wrist while waiting for brachial plexus to recover. Birch et al. suggested to carry out exercises frequently in a day, preferably before every meal [14].

#### **5.3. Splinting**

Eng et al. reported using a wrist/hand cock-up splint with thumb in opposition in patients who were developing early contractures despite regular physiotherapy [2, 15]. Shoulder external rotation splint (airplane splint) can be used to prevent internal rotation contracture at the shoulder.

#### **5.4. Electrical stimulation**

Though electrical stimulation is commonly used in practice, its efficacy is not proved.
