The upper plexus paralysis however does not always extend to all of the above-named muscles; in rare cases, muscles are affected singly, as, for example, isolated deltoid paralysis; in other children, be sides the muscles of the Erb-Duchenne type, additional muscles, e.g., subs•apularis rhomboideus, serratus and pectoralis major may be con comitantly involved. Bilateral plexus paralysis has been observed very rarely.
In the course of the following months, atrophies and contractures occur in the cases which do not recover; prominence of the shoulder bones and lateral flattening of the shoulder are characteristic for a paral ysis of considerable duration. The bony growth of the affected extrem ity is. retarded the general development of the child advances; a subluxation of the humerus in the shoulder-joint sometimes follows, which of itself materially limits the usefulness of the extremity. The most important complications of obstetrical paralysis are injuries to the bones and joints which modify the clinical picture and which may even relegate the symptoms of the paralysis into the background. Frac tures of the humerus, clavicle and scapula, and epiphyseal separation at the upper end of the humerus are not uncommon. Facial palsy and wry neck often accompany the paralysis. A predisposing r61e for the occurrence of obstetrical paralysis has (Well been ascribed to wry neck (Schiiller). The few anatomical findings of obstetrical paralysis show, in recent cases an extravasation of blood into the plexus or else a tear ing of its fibres; in a case of longer duration (examined by Oppenheim and Nonne) degenerations were found in the distribution of the fifth and sixth cervical roots.
The etiology of obstetrical paralysis is still somewhat obscure. Whereas Erb holds energetic pressure of the fingers over the plexus (especially in the application of the Prague mane uvre) responsible, the present opinion is That pressure, either of forceps, or of a narrow pelvis, of a clavicle or finger in carrying out the method of Mauriceau, or else the tearing and stretching resulting from wrongly directed traction with forceps, especially with excessive flexion of the head or bending of the head during the evolving of the shoulder, may be each at times responsible for obstetrical paralysis. Under these manipulations the fifth and sixth cervical nerves would suffer principally (Fieux et al.). According to Peters the pure type of Duchenne-Erb's palsy occurs only in children born with the breech presenting. Obstetrical paralysis has only been twice observed in unassisted labor. Stransky calls attention to asphyxia and the resultant hypervenosity of the blood as a favoring element through which the peripheral nerves are rendered more sus ceptible to trauma.
The diagnosis is easily established. Errors may be made in differ entiating the condition from an immobility of the extremity due to enlargements of the bones. A separation of the upper epiphysis of the
humerus, which likewise is accompanied by inward rotation of the arm, is said to simulate plexus paralysis rather frequently (Kiistner). Care ful examination and the use of the Röntgen rays will protect against this error. The possibility of congenital syphilitic pseudoparalysis or of congenital peripheral paralysis must be considered and excluded by careful scrutiny of the symptom-complex. Infantile cerebral paralysis will hardly cause confusion in diagnosis because of the different state of the muscular tone of the reflexes and the distribution of the paralyses.
The prognosis varies: the fewer the number of muscles involved, the quicker the is re-established and the sooner the treatment is instituted, the better the prognosis. The majority of obstetrical paralyses recover fully; however a considerable number resist treatment either entirely or in part.
The therapy consists in the early application of the faradic or gal vanic current to the diseased muscle; the treatment should be carried out for several minutes daily. Massage and passive movements are used to combat the occurrence of atrophies and contractures. Splints and other orthopedic appliances are employed in older cases; plastic opera tions on the tendons and nerves come into consideration. Mikulicz ob tained a good result in a baby five weeks old, by stretching the plexus which he had exposed with the knife.
Besides the typical obstetrical paralysis of the upper extremity, injuries to other nerves occur, most frequent among which is a periph eral facial paralysis. This may be uni- or bilateral: all or only one of the branches of the facial nerve may be involved. The paralysis occurs as a rule in instrumental labor as a result of the pressure of the blade of the forceps on the trunk of the facial nerve. It occurs only very excep tionally in unassisted labor. It may be caused by an (edema or a hamia toma in the trunk of the facial nerve, which has been produced by the pressure of the bony pelvic ring, in cases of contracted pelvis.
Th, diagnosis is made as in facial paralysis from other causes (which see): the possibility of the paralysis being central (e.g. from congenital cerebral paralysis or congenital mad-development of the facial muscles) must be considered in every case. The prognosis is rela tively a good one. The paralysis disappears in the most instances within a few months.
Obstetrical paralyses of the lower extremities have not often been observed. Injuries and tears of the spinal cord occur only with exces sively energetic attempts at extraction and as a rule lead to the death of the child, themorrhages into the spinal cord, with rare exceptions, give rise to no clinical symptoms.