_In Affections of the Spinal Medulla._--In myelitis, progressive muscular atrophy, poliomyelitis, insular sclerosis, and in traumatic lesions, joint affections are occasionally met with.
The occurrence of joint lesions in _locomotor ataxia_ (tabes dorsalis) was first described by Charcot in 1868--hence the term "Charcot"s disease" applied to them. Although they usually develop in the ataxic stage, one or more years after the initial spinal symptoms, they may appear before there is any evidence of tabes. The onset is frequently determined by some injury. The joints of the lower extremity are most commonly affected, and the disease is bilateral in a considerable proportion of cases--both knees or both hips, for instance, being implicated.
Among the theories suggested in explanation of these arthropathies the most recent is that by Babinski and Barre, which traces the condition to vascular lesions of a syphilitic type in the articular arteries.
The first symptom is usually a swelling of the joint and its vicinity.
There is no redness or heat and no pain on movement. The peri-articular swelling, unlike ordinary dema, scarcely pits even on firm pressure.
[Ill.u.s.tration: FIG. 162.--Bones of Knee-joint in advanced stage of Charcot"s Disease. The medial part of the head of the tibia has disappeared.
(Anatomical Museum, University of Edinburgh).]
In mild cases this condition of affairs may persist for months; in severe cases destructive changes ensue with remarkable rapidity. The joint becomes enormously swollen, loses its normal contour, and the ends of the bones become irregularly deformed (Fig. 162). Sometimes, and especially in the knee, the clinical features are those of an enormous hydrops with fibrinous and other loose bodies and hypertrophied fringes--and great dema of the peri-articular tissues (Fig. 163). The joint is wobbly or flail-like from stretching and destruction of the controlling ligaments, and is devoid of sensation. In other cases, wearing down and total disappearance of the ends of the bones is the prominent feature, attended with flail-like movements and with coa.r.s.e grating. Dislocation is observed chiefly at the hip, and is rather a gross displacement with unnatural mobility than a typical dislocation, and it is usually possible to move the bones freely upon one another and to reduce the displacement. A striking feature is the extensive formation of new bone in the capsular ligament and surrounding muscles.
The enormous swelling and its rapid development may suggest the growth of a malignant tumour. The most useful factor in diagnosis is the entire absence of pain, of tenderness, and of common sensibility. The freedom with which a tabetic patient will allow his disorganised joint to be handled requires to be seen to be appreciated.
[Ill.u.s.tration: FIG. 163.--Charcot"s Disease of Left Knee. The joint is distended with fluid and the whole limb is dematous.]
The rapidity of the destructive changes in certain cases of tabes, and the entire absence of joint lesions in others, would favour the view that special parts of the spinal medulla must be implicated in the former group.
In _syringomyelia_, joint affections (gliomatous arthropathies) are more frequent than in tabes, and they usually involve the upper extremity in correspondence with the seat of the spinal lesion, which usually affects the lower cervical and upper thoracic segments. Except that the joint disease is seldom symmetrical, it closely resembles the arthropathy of tabes. The completeness of the a.n.a.lgesia of the articular structures and of the overlying soft parts is ill.u.s.trated by the fact that in one case the patient himself was in the habit of letting out the fluid from his elbow with the aid of a pair of scissors, and that in another the joint was painlessly excised without an anaesthetic.
[Ill.u.s.tration: FIG. 164.--Charcot"s Disease of both Ankles: front view.
Man, aet. 32.]
The disease may become arrested or may go on to complete disorganisation; suppuration may ensue from infection through a breach of the surface, and in rare cases the joint has become the seat of tuberculosis.
[Ill.u.s.tration: FIG. 165.--Charcot"s Disease of both Ankles: back view.
Man, aet. 32.]
_Treatment_, in addition to that of the nerve lesion underlying the arthropathy, consists in supporting and protecting the joint by means of bandages, splints, and other apparatus. In the lower extremity, the use of crutches is helpful in taking the strain off the affected limb. When there is much distension of the joint, considerable relief follows upon withdrawal of fluid. The best possible result being rigid ankylosis in a good position, it may be advisable to bring this about artificially by arthrodesis or resection. Operation is indicated when only one joint is affected and when the cord lesion is such as will permit of the patient using the limb. The wounds heal well, but the victims of tabes are unfavourable subjects for operative interference, on account of their liability to intercurrent complications. When the limb is quite useless, amputation may be the best course.
_In cerebral lesions_ attended with hemiplegia, joint affections, characterised by evanescent pain, redness, and swelling, are occasionally met with. The secondary changes in joints which are the seat of paralytic contracture are considered with the surgery of the Extremities.
In cases of _hysteria_ and other _functional affections of the nervous system_, an intermittent neuropathic hydrops has been observed--especially in the knee. Without apparent cause, the joint fills with fluid and its movements become restricted, and after from two to eight days the swelling subsides and the joint returns to normal. A remarkable feature of the condition is that the effusion into the joint recurs at regular intervals, it may be over a period of years. Psychic conditions have been known to induce attacks, and sometimes to abort them or even to cause their disappearance. Hence it has been recommended that treatment by suggestion should be employed along with tonic doses of quinine and a.r.s.enic.
HYSTERICAL OR MIMETIC JOINT AFFECTIONS
Under this heading, Sir Benjamin Brodie, in 1822, described an affection of joints, characterised by the prominence of subjective symptoms and the absence of pathological changes. Although most frequently met with in young women with an impressionable nervous system, and especially among those in good social circ.u.mstances, it occurs occasionally in men.
The onset may be referred to injury or exposure to cold, or may be a.s.sociated with some disturbance of the emotions or of the generative organs; or the condition may be an involuntary imitation of the symptoms of organic joint disease presented by a relative or friend.
It is characteristic that the symptoms develop abruptly without satisfactory cause, that they are exaggerated and wanting in harmony with one another, and that they do not correspond with the features of any of the known forms of organic disease. In some cases the only complaint is of severe pain; more often this is a.s.sociated with excessive tenderness and with impairment of the functions of the joint.
On examination the joint presents a normal appearance, but the skin over it is remarkably sensitive. A light touch is more likely to excite pain than deep and firm pressure. Stiffness is a variable feature--in some cases amounting to absolute rigidity, so that no ordinary force will elicit movement. It is characteristic of this, as of other neuroses, that the symptoms come and go without sufficient cause. When the patient"s attention is diverted, the pain and stiffness may disappear. There is no actual swelling of the joint, although there may be an appearance of this from wasting of the muscles above and below. If the joint is kept rigid for long periods, secondary contracture may occur--in the knee with flexion, in the hip with flexion and adduction.
The _diagnosis_ is often a matter of considerable difficulty, and the condition is liable to be mistaken for such organic lesions as a tuberculous or pyogenic focus in the bone close to the joint.
The greatest difficulty is met with in the knee and hip, where the condition may closely simulate tuberculous disease. The use of the Rontgen rays, or examination of the joint under anaesthesia, is helpful.
The _local treatment_ consists chiefly in improving the nutrition of the affected limb by means of ma.s.sage, exercises, baths, and electricity.
Splints are to be avoided. In refractory cases, benefit may follow the application of blisters or of Corrigan"s b.u.t.ton. The general condition of the patient must be treated on the same lines as in other neuroses.
The Weir-Mitch.e.l.l treatment may have to be employed in obstinate cases, the patient being secluded from her friends and placed in charge of a nurse. Complete recovery is the rule, but when the muscles are weak and wasted from prolonged disuse, a considerable time may elapse before the limb returns to normal.
TUMOURS AND CYSTS
New growths taking origin in the synovial membrane are rare, and are not usually diagnosed before operation. They are attended with exudation into the joint, and in the case of _sarcoma_ the fluid is usually blood-stained. If the tumour projects in a polypoidal manner into the joint, it may cause symptoms of loose body. One or two cases have been recorded in which a _cartilaginous tumour_ growing from the synovial membrane has erupted through the joint capsule and infiltrated the adjoining muscles. _Multiple cartilaginous tumours_ forming loose bodies are described on p. 544.
_Cysts of joints_ const.i.tute an ill-defined group which includes ganglia formed in relation to the capsular ligament. Cystic distension of bursae which communicate with the joint is most often met with in the region of the knee in cases of long-standing hydrops. It was suggested by Morrant Baker that cystic swellings may result from the hernial protrusion of the synovial membrane between the stretched fibres of the capsular ligament, and the name "Baker"s cysts" has been applied to these.
In the majority of cases, cysts in relation to joints give rise to little inconvenience and may be left alone. If interfered with at all, they should be excised.
LOOSE BODIES
It is convenient to describe the varieties of loose bodies under two heads: those composed of fibrin, and those composed of organised connective tissue.
#Fibrinous Loose Bodies# (Corpora oryzoidea).--These are h.o.m.ogeneous or concentrically laminated ma.s.ses of fibrin, sometimes resembling rice grains, melon seeds, or adhesive wafers, sometimes quite irregular in shape. Usually they are present in large numbers, but sometimes there is only one, and it may attain considerable dimensions. They are not peculiar to joints, for they are met with in tendon sheaths and bursae, and their origin from synovial membrane may be accepted as proved. They occur in tuberculosis, arthritis deformans, and in Charcot"s disease, and their presence is almost invariably a.s.sociated with an effusion of fluid into the joint. While they may result from the coagulation of fibrin-forming elements in the exudate, their occurrence in tuberculous hydrops would appear to be the result of coagulation necrosis, or of fibrinous degeneration of the surface layer of the diseased synovial membrane. However formed, their shape is the result of mechanical influences, and especially of the movement of the joint.
_Clinically_, loose bodies composed of fibrin const.i.tute an unimportant addition to the features of the disease with which they are a.s.sociated.
They never give rise to the cla.s.sical symptoms a.s.sociated with impaction of a loose body between the articular surfaces. Their presence may be recognised, especially in the knee, by the crepitating sensation imparted to the fingers of the hand grasping the joint while it is flexed and extended by the patient.
The _treatment_ is directed towards the disease underlying the hydrops.
If it is desired to empty the joint, this is best done by open incision.
[Ill.u.s.tration: FIG. 166.--Radiogram of Multiple Loose Bodies in Knee-joint and Semi-membranosus Bursa in a man aet. 38.
(Mr. J. W. Dowden"s case.)]
#Bodies composed of Organised Connective Tissue.#--These are comparatively common in joints that are already the seat of some chronic disease, such as arthritis deformans, Charcot"s arthropathy, or synovial tuberculosis. They take origin almost exclusively from an erratic overgrowth of the fringes of the synovial membrane, and may consist entirely of fat, the arborescent lipoma (Fig. 159) being the most p.r.o.nounced example of this variety. Fibrous tissue or cartilage may form in one or more of the fatty fringes and give rise to hard nodular ma.s.ses, which may attain a considerable size, and in course of time may undergo ossification.
Like other hypertrophies on a free surface, they tend to become pedunculated, and so acquire a limited range of movement. The pedicle may give way and the body become free. In this condition it may wander about the joint, or lie snugly in one of its recesses until disturbed by some sudden movement. A loose body free in a joint is capable of growth, deriving the necessary nutriment from the surrounding fluid. The size and number of the bodies vary widely. Single specimens have been known to attain the size of the patella. The smaller varieties may number considerably over a hundred.
[Ill.u.s.tration: FIG. 167.--Loose Body from Knee-joint of man aet. 25.
Natural size.
a = Convex surface. b = Concave surface.]
In arthritis deformans a rarer type of loose body is met with, a portion of the lipping of one of the articular margins being detached by injury.
In Charcot"s disease, bodies composed of bone are formed in relation to the capsular and other ligaments, and may be made to grate upon one another.
The _clinical features_ in this group are mainly those of the disease which has given rise to the loose bodies, and it is exceptional to meet with symptoms from impaction of the body between the articular surfaces.
Treatment is to be directed towards the primary disease in the joint, as well as to the removal of the loose bodies.
[Ill.u.s.tration: FIG. 168.--Multiple partially ossified Chondromas of Synovial Membrane, from Shoulder-joint, the seat of arthritis deformans, from a man aet. 35.]
_Loose Bodies in Joints which are otherwise healthy._--It is in joints otherwise healthy that loose bodies causing the cla.s.sical symptoms and calling for operative treatment are most frequently met with. They occur chiefly in the knee and elbow of healthy males under the age of thirty.
The complaint may be of vague pains, of occasional cracking on moving the joint, or of impairment of function--usually an inability to extend or flex the joint completely. In many cases a clear account is given of the symptoms which arise when the body is impacted between the articular surfaces, namely, sudden onset of intense sickening pain, loss of power in the limb and locking of the joint, followed by effusion and other accompaniments of a severe sprain. On some particular movement, the body is disengaged, the locking disappears, and recovery takes place.
Attacks of this kind may recur at irregular intervals, during a period of many years. On examining the joint, it is usually found to contain fluid, and there may be points of special tenderness corresponding to the ligaments that have been overstretched. In cases in which there has been recurrent attacks of locking, the ligaments become slack, the joint is wobbly, and the quadriceps is wasted. The patient himself, or the surgeon, may discover the loose body and feel it roll beneath his fingers, especially if it is lodged in the supra-patellar pouch in the knee, or on one or other side of the olecranon in the elbow. In most instances the patient has carefully observed his own symptoms, and is aware not only of the existence of the loose body, but of its erratic appearance at different parts of the joint. This feature serves to differentiate the lesions from a torn medial meniscus in which the pain and tenderness are always in the same spot. As the body usually contains bone, it is recognisable in a skiagram.