Symptoms.-Pronounced changes occur in the trajectory of a divided nerve. The muscles degenerate, atrophy and shorten, and show the reactions of degeneration. When union of the nerve occurs the muscles are restored to a normal condition. If the nerve contains sensory fibers, complete anesthesia (to touch, pain, and temperature) usually follows its division; but if a part is supplied by another nerve as well as by the divided one, anesthesia will not be complete. Trophic changes arise in the paralyzed parts. Among these changes are muscular atrophy; glossy skin; cutaneous eruptions; ulcers; dry gangrene; painless felons; falling of the hair; brittleness, furrowing, or casting off of the nails; jointinflammations; and ankylosis. Immediately after nerve-section vasomotor paralysis comes on, and for a few days the paralyzed part presents a temperature higher than normal. The diagnosis as to which nerve is cut depends upon a study of the distribution of paralysis and anesthesia.'

Treatment. In all recent cases of nerve-section, suture the ends. In 123 cases of primary suture, 119 were cured in from one day to one year (Willard). In 130 cases of secondary suture, 80 per cent. were more or less improved (Willard). If the patient is not seen until long after the accident, incise and apply sutures (secondary sutures); if the nerve cannot be found, extend the incision, find the trunk above and trace it down, and find the trunk below and follow it up. Even after primary suture loss of function is bound to occur for a time. After secondary suture sensation may return in a few days, but it may not return until after a much longer period; in any case muscular function is not restored for months. In partial section of a nerve the ends should be sutured. In secondary suture it may be necessary to perform "lengthening" in order to approximate the ends. Pressure upon nerves may arise from callus, scars, pressure of a dislocated bone or a tumor, or pressure from an external body. The symptoms may be anesthetic, paralytic, and trophic. The treatment is as follows: remove the cause (reduce a dislocated bone, chisel away callus, excise a scar, etc.); then employ massage, douches, and electricity.

Dislocation of the Ulnar Nerve at the Elbow.This condition is very rare. It may occur as a complication of a fracture or a dislocation, or as an uncomplicated condition. It may be produced by violence or by muscular effort, which ruptures the fascia whose function is to retain the nerve back of the inner condyle of the humerus. In some

1 See Bowlby on Injuries of Nerves.

cases the symptoms are slight and transitory, the nerve functionating well in its new situation. As a rule, there are pain, numbness, or anesthesia of the ulnar trajectory, some stiffness of the elbow and stiffness of the little finger or ring finger. The nerve can be felt in front of the inner condyle of the humerus. In some cases neuritis follows, with trophic changes. Treatment.-McCormick's Operation.-Expose the nerve by an incision, incise the fibrous tissue back of the inner condyle, and press the nerve into the bed prepared for it and hold it in place by sutures of kangaroo-tendon passing through the triceps tendon. Wharton advises suturing also "the margin of the fascial expansion of the triceps tendon superficial to the nerve."

Contusion of Nerves.-The symptoms of contusion of nerves may be identical with those of section. Sensation or motion, or both, may be lost. The case may get well in a short time, or the nerve may degenerate as after section. The treatment at first is rest, and later electricity, massage, frictions, and douches.

Punctured Wounds of Nerves.-The symptoms of punctured wounds of nerves may be partly irritative (hyperesthesia, acute pain, and muscular spasm) and partly paralytic (anesthesia, muscular wasting, and paralysis).

The treatment is the same as that for contusion.

3. OPERATIONS UPON NERVES.

Neurorrhaphy, or Nerve-suture.-When a nerve is completely or partially divided by accident it should be sutured. The instruments required are an Esmarch apparatus, a scalpel, blunt hooks, dissecting-forceps, hemostatic forceps, curved needles or sewing-needles, a needleholder, and catgut or kangaroo-tendon. In primary suture render the part bloodless and aseptic. Enlarge the incision if necessary. If the ends can readily be approximated, pass two or three sutures through both the nerve and its sheath

and tie them (Fig. 160). If the ends cannot be approximated, stretch each end and then suture. Remove the Esmarch band, arrest bleeding, suture the wound, dress antiseptically, and put the part in a relaxed position on a splint. After union of the wound remove the splint and use massage,

FIG. 160.--Nerve-suture.

1 A report of fourteen cases of dislocation of the ulnar nerve at the elbow, by H. R. Wharton, Am. Jour. Med. Sciences, Oct., 1895.

frictions, electricity, and the douche. The operation in some instances fails, but in many cases succeeds. In some few cases sensation returns in a few days, but in most cases does not return for many weeks or months. Sensation is restored before motor power. Secondary suture is performed upon cases long after division of a nerve. The part is rendered aseptic and bloodless; an incision is made; the bulbous proximal end is easily found and loosened from its adhesions; the shrunken distal end is sought for and loosened up (it may be necessary to expose the nerve below the wound and trace its trunk upward); the entire bulb of the proximal end is cut off; about one-quarter of an inch of the distal end is removed (Keen); each end is stretched, and the ends are approximated and sewn together. If even stretching does not permit of approximation, adopt one of Bowlby's expedients (Fig. 161), or graft a bit of nerve from a recently amputated limb or

splitting the ends (Beach).

from a lower animal (it makes no dif- FIG. 161-Suture of a nerve by ference as to whether the grafted

nerve were motor, sensory, or mixed). Mayo Robson has succeeded in grafting the spinal cord of a rabbit in the median nerve of a man. The restoration of function was complete. Von Bergmann suggests shortening the limb by excising a piece of bone. Létiévant has attached the cut end of the peripheral portion of a divided nerve to an adjacent uncut nerve. Assaky uses the suture à distance, catgut passing from end to end and serving as a bridge for reparative material.

Neurectasy, Neurotomy, and Neurectomy.-Neurectasy, or nerve-stretching, may be applied to motor, sensory, or mixed nerves. A nerve can be stretched about one-twentieth of its length (Vogt). Neurectasy has been employed for neuralgia, neuritis, muscular spasm, hyperesthesia, anesthesia, painful ulcer, perforating ulcer, and the pains of locomotor ataxia. The operation, which was once the fashion, seems to benefit some cases, but it is not now thought so highly of as formerly. The incision for neurectasy is identical with the incision for neurectomy or neurotomy of the same nerve. Neurotomy, or section of a nerve, is only performed upon small and purely sensory nerves. It is performed chiefly for peripheral neuralgia or for some other painful malady. It is useless because sensation soon returns. Paget saw return of sensation entirely in four weeks after division of the median

nerve. Corning endeavors to prevent this regeneration by inserting oil between the ends. He uses oil of theobroma containing enough paraffin to make the melting-point 105°. The oil is melted, is injected around the nerve, and cold is applied. The nerve is now sectioned with a canaliculated knife, the ends are separated widely, more oil is injected, and cold is again applied. The theory is that this oil, which is solid at the temperature of the body, devitalizes the nerve at the point of section and acts as a barrier to the passage of regenerating fibers. This method has been applied especially in cervicobrachial neuralgia.' Neurectomy, or excision of a portion of a nerve-trunk, is only applicable to sensory nerves and to painful affections.

Stretching of the Sciatic Nerve.-Some surgeons stretch the sciatic nerve by anesthetizing the patient and holding the leg and thigh in line, strong flexion being made upon the hip, the entire lower extremity being used as a lever (Keen). This method, which has caused death, inflicts needless damage, and the operative plan is safer and better. The instruments required are a scalpel, hemostatic forceps, dissecting-forceps, an Allis dissector, retractors, and a scale with a handle and a hook. The patient lies prone, the thighs and legs being extended. An incision four inches in length is made a little external to the middle of the thigh, and going at once through the deep fascia; the biceps is found and is drawn outward; the nerve is discovered between the retracted biceps on the outside and the semitendinosus on the inside, resting upon the adductor magnus muscle. The nerve, which is caught up by the finger, is first pulled down. from the spine and then up from the periphery, and finally the hook of the scale is inserted beneath the trunk and the nerve is stretched to the extent of forty pounds. Very rarely is even a single ligature needed. The wound is sutured and dressed. If the incision is made at a higher level below the gluteo-femoral crease, the sciatic nerve will be found just by the outer border of the biceps.

Neurectomy of the Infraorbital Nerve.-The instru ments required in this operation are a scalpel, dissectingforceps, aneurysm-needle, hemostatic forceps, blunt hooks, an Allis dissector, and metal retractors. The patient lies upon his back, the head being a little raised by pillows. The surgeon stands to the outside of, and faces, the patient. A curved incision one and a half inches long is made below the lower border of the orbit. The nerve lies in a line

1 Med. Rec., Dec. 5, 1896.

dropped from the supraorbital notch to between the two lower bicuspid teeth. The nerve is found upon the levator labii superioris muscle, and a piece of silk is passed under the nerve by an aneurysm-needle and firmly fastened. The upper border of the incision is drawn upward; the periosteum of the floor of the orbit is elevated and held by a retractor; the roof of the infraorbital canal is broken through; the nerve is picked up far back with the blunt hook and is divided with scissors, and the entire nerve is drawn out by making traction upon the silk. The bleeding in the orbit is checked by pressure. The wound is stitched without drainage.

Neurectomy of the Supraorbital Nerve.-In this operation shave off the eyebrow. The instruments required and the position of the patient are as for the operation upon the infraorbital nerve. A curved incision one inch long discloses the nerve as it emerges from the supraorbital notch or foramen at the junction of the inner and middle thirds of the eyebrow. The nerve is pulled forward and cut off above and below.

Neurectomy of the Inferior Dental Nerve. The instruments are the same as for any other neurectomy, and in addition a chisel, a mallet, and a rongeur forceps. Make a curved incision around the angle of the jaw. Lift the supramaxillary branch of the facial nerve downward (Kocher). Separate the masseter muscle with a periosteum-elevator and slight touches with the knife. Chisel an opening in the center of the ascending ramus (Velpeau's rule). This opening exposes the beginning of the dental canal (Kocher). If necessary, the opening may be enlarged with a rongeur. Pull the nerve out with a hook and remove a piece from it.

Removal of the Gasserian Ganglion.-This operation is dangerous, bloody, and difficult, and is only undertaken in very severe cases of tic douloureux, and in cases upon which less grave procedures have failed. The operation usually cures the pain if the patient recovers from the actual procedure. The mortality is from 12 to 15 per cent. In some cases the pain has subsequently returned. Out of Keen's 9 cases of removal, 3 had corneal trouble, but in not one case was the eye lost. Some atrophy is apt to be noted in the tongue, and the eye becomes insensitive and watery.

Operation. The surgeon is provided with the instruments for osteoplastic resection of the skull. Krause and others employ a surgical engine. Special retractors, various hooks, scalpels, a dry dissector, dissecting- and hemostatic forceps,