The cutaneous neuro-fibroma or molluscum fibrosum has been shown by Recklinghausen to be a soft fibroma related to the terminal filaments of one of the cutaneous nerves ([Fig. 88]). The disease appears in the form of multiple, soft, projecting tumours, scattered all over the body, except the palms of the hands and soles of the feet. The tumours are of all sizes, some being no larger than a pin's head, whilst many are as big as a filbert and a few even larger. Many are sessile and others are distinctly pedunculated, but all are covered with skin. They are mobile, soft to the touch, and of the consistence of firm fat. In exceptional cases one of the skin tumours may attain an enormous size and cause a hideous deformity, hanging down by its own weight in lobulated or folded masses (pachy-dermatocele). The treatment consists in removing the larger swellings. In some cases molluscum fibrosum is associated with pigmentation of the skin and with multiple tumours of the nerve-trunks. The small multiple tumours rarely call for interference.
Fig. 89.—Elephantiasis Neuromatosa in a woman æt. 28
Elephantiasis neuromatosa is the name applied by Virchow to a condition in which a limb is swollen and misshapen as a result of the extension of a neuro-fibromatosis to the skin and subcutaneous cellular tissue of the extremity as a whole ([Fig. 89]). It usually begins in early life without apparent cause, and it may be associated with multiple tumours of the nerve-trunks. The inconvenience caused by the bulk and weight of the limb may justify its removal.
SURGERY OF THE INDIVIDUAL NERVES[6]
[6] We desire here to acknowledge our indebtedness to Mr. James Sherren's work on Injuries of Nerves and their Treatment.
The Brachial Plexus.—Lesions of the brachial plexus may be divided into those above the clavicle and those below that bone.
In the supra-clavicular injuries, the violence applied to the head or shoulder causes over-stretching of the anterior branches (primary divisions) of the cervical nerves, the fifth, or the fifth and sixth being those most liable to suffer. Sometimes the traction is exerted upon the plexus from below, as when a man in falling from a height endeavours to save himself by clutching at some projection, and the lesion then mainly affects the first dorsal nerve. There is tearing of the nerve sheaths, with hæmorrhage, but in severe cases partial or complete severance of nerve fibres may occur and these give way at different levels. During the healing process an excess of fibrous tissue is formed, which may interfere with regeneration.
Post-anæsthetic paralysis occurs in patients in whom, during the course of an operation, the arm is abducted and rotated laterally or extended above the head, causing over-stretching of the plexus, especially of the fifth, or fifth and sixth, anterior branches.