Congenital chickenpox infection may produce brachial plexus damage. The damage usually involves the cervical anterior horn motor neurons. Other central nervous system areas may be involved. Clinical manifestations include arm monoparesis and cutaneous scarring (Figure 264.1). Horner syndrome may also be present. Congenital chickenpox is the result of fetal infection by the varicella virus during early pregnancy. No specific treatment is available. Physical therapy is recommended. Surgical treatment of limb deformities and tendon transplant can be attempted when the patient is older.
Figure 264.1.— Intrauterine chickenpox infection. [A] Left Horner syndrome, atrophy of the left arm and absence of the left thumb. [B] Scar formation in shoulder region.