Further Outpatient Care
See Rehabilitation Program.
Complications
Children with brachial plexus palsy are at risk of developing complications, such as progressive contractures, bony deformities, scoliosis, posterior shoulder dislocation, and agnosia of the affected limb.
Prognosis
Statistics on children who attain complete recovery after brachial plexus palsy (BPP) vary widely, with reports ranging from 4-93%. This discrepancy is due, at least in part, to the time of evaluation. Many children present to the newborn nursery with temporary weakness (neurapraxia) that resolves prior to discharge and is thus unaccounted for in most of these studies.
Each child with more severe injuries presents with a slightly different degree of injury and responds differently to growth and therapeutic interventions. [53] Experience in treating children teaches that children who present at 2 weeks of age with no signs of recovery generally are subject to development of sequelae, including mild scapular winging, inability to supinate the forearm fully, limitation in shoulder abduction, and forward flexion.
Peripheral nerves remyelinate at a rate of 1 mm/day. Thus, if the nerve is not transected, recovery can be expected by 4-5 months in Erb palsy, 6-7 months for an upper-middle trunk palsy, and 14 months for a total BPP. Some authors believe that infants who do not show signs of spontaneous recovery by 3-5 months usually are left with residual deficits if managed conservatively. Papazian and associates add that unfavorable functional outcome is related more often to aberrant reinnervation than to lack of reinnervation. [54] Aberrant reinnervation is especially common in brachial plexus lesions secondary to the close proximity of the nerves involved.
As one might expect, findings consistent with a more extensive initial injury (Horner syndrome and total BPP) portend a less favorable prognosis. The converse also is true; children with isolated upper trunk lesions generally have a better prognosis. The presence or absence of phrenic nerve involvement does not appear to have prognostic value in BPP.
Yilmaz and coworkers compared MRI, electrophysiologic studies, and muscle strength scoring in 13 infants with BPP to determine which indicator provided the most accurate prognosis of the outcome at 1 year. [22] They found that scoring of muscle strength (eg, elbow flexion; wrist, finger, and thumb extension) was the most reliable measure, with 94.8% confidence at 3 months. Electrophysiologic studies, while helpful in identifying patients with an unfavorable prognosis, occasionally are overoptimistic (in 1 of 13 cases). MRI findings of pseudomeningoceles were seen in 2 of 5 patients with an unfavorable prognosis and in 2 of 8 with a good prognosis.
A study by Buitenhuis et al found reduced sensibility of the thumb and index finger in children with neonatal BPP associated with C5 and C6, following either conservative or surgical treatment. [55]
Michelow and colleagues retrospectively studied 66 children with BPP. [56] They found that elbow flexion capacity at 3 months correlated well with good recovery of the arm at 1 year; however, predictions based on the presence or absence of elbow flexion at 3 months were incorrect in 12.8% of cases. When elbow flexion was combined with other physical findings (eg, improved extension of the elbow, wrist, thumb, finger), the prediction was incorrect in only 5.2% of cases.
Eng and associates pointed out that most patients who are treated conservatively exhibit a return of biceps function. [8] Biceps strength at 3-4 months, therefore, should not be the sole selection criterion for neurosurgical intervention. Many children did not show reinnervation of the biceps until 4-6 months of age, the forearm until 7-8 months, and the hand muscles (when affected) until 12-14 months. EMG signs of reinnervation are apparent 3-4 weeks before clinical recovery is seen. With conservative management alone, motor function continues to improve until age 2.5 years.
Eng classified sequelae as mild, moderate, and severe. Mild impairment was defined as minimal winging of the scapula, shoulder abduction to 90° or more, minimal limitation of shoulder rotation and elbow supination, normal hand function, and normal sweat and sensation. [8] Moderate impairment included moderate winging of the scapula, shoulder abduction of less than 90° with substitution by other muscles, elbow flexion contracture, no supination, weak wrist and finger extensors, good hand intrinsic muscles, and some loss of sweat and sensation. Severe impairment was defined as marked winging of the scapula, shoulder abduction less than 45°, severe elbow flexion contracture, no supination, poor or no hand function, severe loss of sweat and sensation, or agnosia of the limb.
Outcomes were followed in 149 children whose cases were managed conservatively. A total of 4% recovered completely, 62% developed mild sequelae, 19% had moderate symptoms, and 15% sustained severe impairment.
In 1999, Waters performed a retrospective analysis of 94 children with BPP, comparing outcomes following neurosurgical repair, tendon transfers, osteotomy of the humerus, and conservative management. [57] The investigators looked at 66 infants with BPP who presented in the first 3 months of life; 6 underwent microsurgical repair after no clinical improvement was seen in biceps contraction and antigravity strength at 6 months. Twenty-seven patients were referred after 6 months, secondary to persistent deficits; latissimus and teres major transfer was performed in 9 patients and a humeral derotation osteotomy in 7 for weakness in external rotation or tightness of the internal rotators.
The patients who underwent microsurgical repair had more favorable outcomes (based on the Mallet classification) than did those who did not have biceps function by 5 months, but their outcomes were not better than those who had a return of biceps function by 4 months. The Mallet scores, 4 in each category on average, after tendon transfers and osteotomy were equal to those of children who spontaneously regained biceps function in the first 3 months of life. Despite the small sample size, the investigators concluded that microsurgical repair leads to improved function in children who have not had clinical improvement of the biceps by 6 months. If biceps function by 3 months has been used as the main criterion for neurosurgical intervention, 39 additional patients would have qualified.
In 2004, Smith and colleagues concluded a 13-year prospective study that looked at the long-term outcome of patients with absent biceps function at 3 months. [58] Of the 170 patients studied, 28 had absent biceps function at 3 months. Twenty-seven of the 28 had at least antigravity biceps function at the time of follow-up. The researchers concluded that patients with C5-C6 injury and absent biceps function at age 3 months often have good long-term shoulder function without brachial plexus surgery.
Fisher and associates studied the utility of elbow flexion as a criterion to recommend nonoperative treatment for obstetrical BPP. [59] They studied 209 cases through retrospective chart review and organized them in 4 groups: Group A, no elbow flexion at 3 months (operative); Group B, elbow flexion at 3 months (operative); Group C, no elbow flexion at 3 months (nonoperative); and Group D, elbow flexion at 3 months (nonoperative). Elbow flexion was measured with the Active Movement Scale. The investigators found that Groups A, B, and C experienced a statistically significant increase in elbow function by the end of the study period (3 years), with no statistically significant differences between the 3 groups by the end of the study period. Group D showed statistically significant improvement by 3 months, compared with the other groups, leading most patients to be discharged from the clinic before the end of the 3-year study period.
Patient Education
See Physical Therapy.
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Brachial Plexus. Image courtesy of Michael Brown, MD.
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Mallet classification.
