Manual of Surgery Volume I Part 37

Two clinical types are recognised, one in which the disease progresses slowly and remains confined to the cervical glands for two or more years; the other, in which the disease is more rapidly disseminated and causes death in from twelve to eighteen months.

[Ill.u.s.tration: FIG. 81.--Lymphadenoma (Hodgkin's Disease) affecting left side of neck and left axilla, in a woman aet. 44. Three years' duration.]

In the acute form, the health suffers, there is fever, and the glands may vary in size with variations in the temperature; the blood presents the characters met with in secondary anaemia. The spleen, liver, testes, and mammae may be enlarged; the glandular swellings press on important structures, such as the trachea, sophagus, or great veins, and symptoms referable to such pressure manifest themselves.

_Diagnosis._--Considerable difficulty attends the diagnosis of lymphadenoma at an early stage. The negative results of tuberculin tests may a.s.sist in the differentiation from tuberculous disease, but the more certain means of excising one of the suspected glands and submitting it to microscopical examination should be had recourse to. The sections show proliferation of endothelial cells, the formation of numerous giant cells quite unlike those of tuberculosis and a progressive fibrosis.

Lympho-sarcoma can usually be differentiated by the rapid a.s.sumption of the local features of malignant disease, and in a gland removed for examination, a predominance of small round cells with scanty protoplasm.

The enlargement a.s.sociated with leucocythaemia is differentiated by the characteristic changes in the blood.

_Treatment._--In the acute form of lymphadenoma, treatment is of little avail. a.r.s.enic may be given in full doses either by the mouth or by subcutaneous injection; the intravenous administration of neo-salvarsan may be tried. Exposure to the X-rays and to radium has been more successful than any other form of treatment. Excision of glands, although sometimes beneficial, seldom arrests the progress of the disease. The ease and rapidity with which large ma.s.ses of glands may be sh.e.l.led out is in remarkable contrast to what is observed in tuberculous disease. Surgical interference may give relief when important structures are being pressed upon--tracheotomy, for example, may be required where life is threatened by asphyxia.

#Leucocythaemia.#--This is a disease of the blood and of the blood-forming organs, in which there is a great increase in the number, and an alteration of the character, of the leucocytes present in the blood. It may simulate lymphadenoma, because, in certain forms of the disease, the lymph glands, especially those in the neck, axilla, and groin, are greatly enlarged.

TUMOURS OF LYMPH GLANDS

#Primary Tumours.#--_Lympho-sarcoma_, which may be regarded as a sarcoma starting in a lymph gland, appears in the neck, axilla, or groin as a rapidly growing tumour consisting of one enlarged gland with numerous satellites. As the tumour increases in size, the sarcomatous tissue erupts through the capsule of the gland, and infiltrates the surrounding tissues, whereby it becomes fixed to these and to the skin.

[Ill.u.s.tration: FIG. 82.--Lympho-Sarcoma removed from Groin. It will be observed that there is one large central parent tumour surrounded by satellites.]

The prognosis is grave in the extreme, and the only hope is in early excision, followed by the use of radium and X-rays. We have observed a case of lympho-sarcoma above the clavicle, in which excision of all that was removable, followed by the insertion of a tube of radium for ten days, was followed by a disappearance of the disease over a period which extended to nearly five years, when death resulted from a tumour in the mediastinum. In a second case in which the growth was in the groin, the patient, a young man, remained well for over two years and was then lost sight of.

#Secondary Tumours.#--Next to tuberculosis, _secondary cancer_ is the most common disease of lymph glands. In the neck it is met with in a.s.sociation with epithelioma of the lip, tongue, or fauces. The glands form tumours of variable size, and are often larger than the primary growth, the characters of which they reproduce. The glands are at first movable, but soon become fixed both to each other and to their surroundings; when fixed to the mandible they form a swelling of bone-like hardness; in time they soften, liquefy, and burst through the skin, forming foul, fungating ulcers. A similar condition is met with in the groin from epithelioma of the p.e.n.i.s, s.c.r.o.t.u.m, or v.u.l.v.a. In cancer of the breast, the infection of the axillary glands is an important complication.

In _pigmented_ or _melanotic cancers_ of the skin, the glands are early infected and increase rapidly, so that, when the primary growth is still of small size--as, for example, on the sole of the foot--the femoral glands may already const.i.tute large pigmented tumours.

[Ill.u.s.tration: FIG. 83.--Cancerous Glands in Neck secondary to Epithelioma of Lip.

(Mr. G. L. Chiene's case.)]

The implication of the glands in other forms of cancer will be considered with regional surgery.

_Secondary sarcoma_ is seldom met with in the lymph glands except when the primary growth is a lympho-sarcoma and is situated in the tonsil, thyreoid, or t.e.s.t.i.c.l.e.

CHAPTER XVI

THE NERVES

Anatomy--INJURIES OF NERVES: Changes in nerves after division; Repair and its modifications; Clinical features; _Primary and secondary suture_--SUBCUTANEOUS INJURIES OF NERVES--DISEASES: _Neuritis_; _Tumours_--Surgery of the individual nerves: _Brachial neuralgia_; _Sciatica_; _Trigeminal neuralgia_.

#Anatomy.#--A nerve-trunk is made up of a variable number of bundles of nerve fibres surrounded and supported by a framework of connective tissue. The nerve fibres are chiefly of the medullated type, and they run without interruption from a nerve cell or _neuron_ in the brain or spinal medulla to their peripheral terminations in muscle, skin, and secretory glands.

Each nerve fibre consists of a number of nerve fibrils collected into a central bundle--the axis cylinder--which is surrounded by an envelope, the neurolemma or sheath of Schwann. Between the neurolemma and the axis cylinder is the medullated sheath, composed of a fatty substance known as myelin. This medullated sheath is interrupted at the nodes of Ranvier, and in each internode is a nucleus lying between the myelin and the neurolemma. The axis cylinder is the essential conducting structure of the nerve, while the neurolemma and the myelin act as insulating agents. The axis cylinder depends for its nutrition on the central neuron with which it is connected, and from which it originally developed, and it degenerates if it is separated from its neuron.

The connective-tissue framework of a nerve-trunk consists of the _perineurium_, or general sheath, which surrounds all the bundles; the _epineurium_, surrounding individual groups of bundles; and the _endoneurium_, a delicate connective tissue separating the individual nerve fibres. The blood vessels and lymphatics run in these connective-tissue sheaths.

According to Head and his co-workers, Sherren and Rivers, the afferent fibres in the peripheral nerves can be divided into three systems:--

1. Those which subserve _deep sensibility_ and conduct the impulses produced by pressure as well as those which enable the patient to recognise the position of a joint on pa.s.sive movement (joint-sensation), and the kinaesthetic sense, which recognises that active contraction of the muscle is taking place (active muscle-sensation). The fibres of this system run with the motor nerves, and pa.s.s to muscles, tendons, and joints. Even division of both the ulnar and the median nerves above the wrist produces little loss of deep sensibility, unless the tendons are also cut through. The failure to recognise this form of sensibility has been largely responsible for the conflicting statements as to the sensory phenomena following operations for the repair of divided nerves.

2. Those which subserve _protopathic_ sensibility--that is, are capable of responding to painful cutaneous stimuli and to the extremes of heat and cold. These also endow the hairs with sensibility to pain. They are the first to regenerate after division.

3. Those which subserve _epicritic_ sensibility, the most highly specialised, capable of appreciating light touch, _e.g._ with a wisp of cotton wool, as a well-localised sensation, and the finer grades of temperature, called cool and warm (72104 F.), and of discriminating as separate the points of a pair of compa.s.ses 2 cms. apart. These are the last to regenerate.

A nerve also exerts a trophic influence on the tissues in which it is distributed.

The researches of Stoffel on the minute anatomy of the larger nerves, and the disposition in them of the bundles of nerve fibres supplying different groups of muscles, have opened up what promises to be a fruitful field of clinical investigation and therapeutics. He has shown that in the larger nerve-trunks the nerve bundles for special groups of muscles are not, as was formerly supposed, arranged irregularly and fortuitously, but that on the contrary the nerve fibres to a particular group of muscles have a typical and practically constant position within the nerve.

In the large nerve-trunks of the limbs he has worked out the exact position of the bundles for the various groups of muscles, so that in a cross section of a particular nerve the component bundles can be labelled as confidently and accurately as can be the cortical areas in the brain. In the living subject, by using a fine needle-like electrode and a very weak galvanic current, he has been able to differentiate the nerve bundles for the various groups of muscles. In several cases of spastic paralysis he succeeded in picking out in the nerve-trunk of the affected limb the nerve bundles supplying the spastic muscles, and, by resecting portions of them, in relieving the spasm. In a case of spastic contracture of the p.r.o.nator muscles of the forearm, for example, an incision is made along the line of the median nerve above the bend of the elbow. At the lateral side of the median nerve, where it lies in contact with the biceps muscle, is situated a well-defined and easily isolated bundle of fibres which supplies the p.r.o.nator teres, the flexor carpi radialis, and the palmaris longus muscles. On incising the sheath of the nerve this bundle can be readily dissected up and its ident.i.ty confirmed by stimulating it with a very weak galvanic current. An inch or more of the bundle is then resected.

INJURIES OF NERVES

Nerves are liable to be cut or torn across, bruised, compressed, stretched, or torn away from their connections with the spinal medulla.

#Complete Division of a Mixed Nerve.#--Complete division is a common result of accidental wounds, especially above the wrist, where the ulnar, median, and radial nerves are frequently cut across, and in gun-shot injuries.

_Changes in Structure and Function._--The mere interruption of the continuity of a nerve results in degeneration of its fibres, the myelin being broken up into droplets and absorbed, while the axis cylinders swell up, disintegrate, and finally disappear. Both the conducting and the insulating elements are thus lost. The degeneration in the central end of the divided nerve is usually limited to the immediate proximity of the lesion, and does not even involve all the nerve fibres. In the distal end, it extends throughout the entire peripheral distribution of the nerve, and appears to be due to the cutting off of the fibres from their trophic nerve cells in the spinal medulla. Immediate suturing of the ends does not affect the degeneration of the distal segment. The peripheral end undergoes complete degeneration in from six weeks to two months.

The physiological effects of complete division are that the muscles supplied by the nerve are immediately paralysed, the area to which it furnishes the sole cutaneous supply becomes insensitive, and the other structures, including tendons, bones, and joints, lose sensation, and begin to atrophy from loss of the trophic influence.

#Nerves divided in Amputation.#--In the case of nerves divided in an amputation, there is an active, although necessarily abortive, attempt at regeneration, which results in the formation of bulbous swellings at the cut ends of the nerves. When there has been suppuration, and especially if the nerves have been cut so as to be exposed in the wound, these bulbous swellings may attain an abnormal size, and are then known as "amputation" or "stump neuromas" (Fig. 84).

When the nerves in a stump have not been cut sufficiently short, they may become involved in the cicatrix, and it may be necessary, on account of pain, to free them from their adhesions, and to resect enough of the terminal portions to prevent them again becoming adherent. When this is difficult, a portion may be resected from each of the nerve-trunks at a higher level; and if this fails to give relief, a fresh amputation may be performed. When there is agonising pain dependent upon an ascending neuritis, it may be necessary to resect the corresponding posterior nerve roots within the vertebral ca.n.a.l.

[Ill.u.s.tration: FIG. 84.--Stump Neuromas of Sciatic Nerve, excised forty years after the original amputation by Mr. A. G. Miller.]

#Other Injuries of Nerves.#--_Contusion_ of a nerve-trunk is attended with extravasation of blood into the connective-tissue sheaths, and is followed by degeneration of the contused nerve fibres. Function is usually restored, the conducting paths being re-established by the formation of new nerve fibres.

When a nerve is _torn across_ or badly _crushed_--as, for example, by a fractured bone--the changes are similar to those in a divided nerve, and the ultimate result depends on the amount of separation between the ends and the possibility of the young axis cylinders bridging the gap.

_Involvement of Nerves in Scar Tissue._--Pressure or traction may be exerted upon a nerve by contracting scar tissue, or a process of neuritis or perineuritis may be induced.

When terminal filaments are involved in a scar, it is best to dissect out the scar, and along with it the ends of the nerves pressed upon.

When a nerve-trunk, such as the sciatic, is involved in cicatricial tissue, the nerve must be exposed and freed from its surroundings (_neurolysis_), and then stretched so as to tear any adhesions that may be present above or below the part exposed. It may be advisable to displace the liberated nerve from its original position so as to minimise the risk of its incorporation in the scar of the original wound or in that resulting from the operation--for example, the radial nerve may be buried in the substance of the triceps, or it may be surrounded by a segment of vein or portion of fat-bearing fascia.

_Injuries of nerves resulting from_ #gun-shot wounds# include: (1) those in which the nerve is directly damaged by the bullet, and (2) those in which the nerve-trunk is involved secondarily either by scar tissue in its vicinity or by callus following fracture of an adjacent bone. The primary injuries include contusion, partial or complete division, and perforation of the nerve-trunk. One of the most constant symptoms is the early occurrence of severe neuralgic pain, and this is usually a.s.sociated with marked hyperaesthesia.

#Regeneration.#--_Process of Repair when the Ends are in Contact._--_If the wound is aseptic_, and the ends of the divided nerve are sutured or remain in contact, they become united, and the conducting paths are re-established by a regeneration of nerve fibres. There is a difference of opinion as to the method of regeneration. The Wallerian doctrine is that the axis cylinders in the central end grow downwards, and enter the nerve sheaths of the distal portion, and continue growing until they reach the peripheral terminations in muscle and skin, and in course of time acquire a myelin sheath; the cells of the neurolemma multiply and form long chains in both ends of the nerve, and are believed to provide for the nourishment and support of the actively lengthening axis cylinders. Another view is that the formation of new axis cylinders is not confined to the central end, but that it goes on also in the peripheral segment, in which, however, the new axis cylinders do not attain maturity until continuity with the central end has been re-established.

_If the wound becomes infected_ and suppuration occurs, the young nerve fibres are destroyed and efficient regeneration is prevented; the formation of scar tissue also may const.i.tute a permanent obstacle to new nerve fibres bridging the gap.

_When the ends are not in contact_, reunion of the divided nerve fibres does not take place whether the wound is infected or not. At the proximal end there forms a bulbous swelling, which becomes adherent to the scar tissue. It consists of branching axis cylinders running in all directions, these having failed to reach the distal end because of the extent of the gap. The peripheral end is completely degenerated, and is represented by a fibrous cord, the cut end of which is often slightly swollen or bulbous, and is also incorporated with the scar tissue of the wound.