(BQ) Part 2 book “Brachial plexus injuries” has contents: Surgical technique, results of surgery after breech delivery, treatment of co-contraction, war injuries, traumatic brachial plexus injuries in children, medial rotation contracture and posterior dislocation of the shoulder, and other contents. | Obstetrical Paralysis 16 Aetiology JM Hans Ubachs and Albert (Bart) CJ Slooff History The aetiology of the obstetric brachial plexus injuries has an interesting history. As early as 1764, Smellie suggested the obstetric origin of a paralysis of the arm in children. But only in 1872, in the third edition of his book De l’électrisation localisée et de son application à la pathologie et à la thérapeutique, Duchenne de Boulogne described four children with an upper brachial plexus lesion as a result of an effort to deliver the shoulder. The classical description by Erb in 1874 concerned the upper brachial plexus paralysis in adults, with the same characteristics as those described by Duchenne de Boulogne. Using electric stimulation, he found in healthy persons a distinct point on the skin in the suprascapular region, just anterior to the trapezius muscle, where the same muscle groups could be contracted as those affected in his patients. It is the spot where the fifth and sixth cervical roots unite, and where they are optimally accessible to electric current by virtue of their superficial position. Pressure on this ‘point of Erb’, caused either by fingers by traction on the armpits, by forceps applied too deep, or by a haematoma were for Erb, and many obstetricians after him, the only possible cause of the lesion. But not everybody accepted the compression theory. Poliomyelitis and toxic causes were mentioned. Some even pointed to the possibility of an epiphysiolysis of the humerus, caused by congenital lues, and consequently a paralysis of the arm. Doubts about the pressure theory, however, were raised as a result of observation of Horner’s syndrome, indicating damage of the sympathical nerve, together with an injury of the lower plexus. Augusta Klumpke, the first female intern in Paris, explained in 1885 Horner’s sign in the brachial plexus lesion by avulsions of the roots C8–T1 and involvement of the homolateral cervical sympathic nervous system (Klumpke 1885).
