#Arthritis deformans# occurs as a hydrops with hypertrophy of the synovial fringes and loose bodies, or as a dry arthritis with eburnation and lipping of the articular margins.
#Neuro-arthropathies# are met with chiefly in syringomyelia, and are attended with striking alterations in the shape of the bones and with abnormal mobility.
#Pyogenic diseases# result from staphylococcal osteomyelitis--chiefly of the humerus or ulna--and from gonorrha.
The remaining diseases at the elbow include syphilitic disease in young children, bleeder"s joint, hysterical affections, and loose bodies, and do not call for special description.
#Ankylosis# of the elbow-joint, if interfering with the livelihood of the patient, may be got rid of by resecting the articular ends of the bones, or by inserting between them a flap of fascia and subcutaneous fat derived from the posterior aspect of the upper arm--_arthroplasty_.
THE WRIST-JOINT
The close proximity of the flexor sheaths to the carpal articulations permits of infective processes spreading readily from one to the other. The arrangement of the synovial membranes also favours the extension of disease throughout the numerous articulations in the region of the wrist.
#Tuberculous disease# is met with chiefly in young adults, but may occur at any age. It usually originates in the synovial membrane, but foci are frequently present in the carpal bones, and less commonly in the lower ends of the radius and ulna, or in the bases of the metacarpals. The clinical features are almost invariably those of white swelling, which is most marked on the dorsum where it obscures the bony prominences and the outlines of the extensor tendons. Wasting of the thenar and hypothenar eminences, and filling up of the hollows above and below the anterior annular ligament, render the appearance on the palmar aspect characteristic.
The att.i.tude is one of slight flexion with drooping of the hand and fingers. The fingers become stiff as a result of adhesions in the tendon sheaths, and the power of opposing the thumb and fingers may be lost. Pain is usually absent until the articular surfaces become carious. Softening of the ligaments may permit of lateral mobility, and sometimes partial dislocation occurs. Abscess may be followed by sinuses and infection of the tendon sheaths, especially those in the palm.
The localisation of disease in individual bones or joints can be determined by the use of the X-rays.
_Treatment._--Conservative measures may be persevered with over a longer period than in most other joints. The forearm, wrist, and metacarpus are immobilised in the att.i.tude of dorsal flexion, while the fingers and thumb are left free to allow of pa.s.sive movements. It may be necessary to give an anaesthetic to obtain the necessary degree of dorsiflexion. To inject iodoform, the needle is inserted immediately below the radial or the ulnar styloid process. Sometimes the carpal bones are so soft that the needle can be made to penetrate them in different directions. Operative treatment is indicated in cases which resist conservative measures, or when the general health calls for speedy removal of the disease.
_Other diseases of the wrist_ are comparatively rare. They include pyogenic affections, such as those resulting from infective conditions in the palm of the hand, different types of gonorrhal, rheumatic, and gouty affections, and arthritis deformans. An interesting feature, sometimes met with in arthritis deformans, consists in eburnation of the articular surfaces of the carpal bones, although the range of movement is almost nil.
THE HIP-JOINT
Owing to the depth of this joint from the surface, it is not possible to detect the presence of effusion or of synovial thickening as readily as in other joints, hence in the recognition of hip disease we have to rely largely upon indirect evidence, such as a limp in walking, an alteration in the att.i.tude of the limb, or restriction of its movements.
The whole of the anterior and fully one-half of the posterior aspect of the neck of the femur is covered by synovial membrane, so that lesions not only of the epiphysis and epiphysial junction, but also of the neck of the bone, are capable of spreading directly to the synovial membrane and to the cavity of the joint. Conversely, disease in the synovial membrane may spread to the bone in relation to it.
Infective material may escape from the joint into the surrounding tissues through any weak point in the capsule, particularly through the bursa which intervenes between the capsule and the ilio-psoas, and which in one out of every ten subjects communicates with the joint.
TUBERCULOUS DISEASE
Tuberculous disease of the hip, morbus c.o.xae, or "hip-joint disease,"
is especially common in the poorer cla.s.ses. It is a frequent cause of prolonged invalidism, and of permanent deformity, and is attended with a considerable mortality. It is essentially a disease of early life, rarely commencing after p.u.b.erty, and almost never after maturity.
#Pathological Anatomy.#--Bone lesions bulk more largely in hip disease than they do in disease of other joints--five cases originating in bone to one in synovial membrane being the usual estimate. The upper end of the femur and the acetabulum are affected with about equal frequency.
In addition to primary tuberculous lesions, secondary changes result from the inflamed and softened bones pressing against one another subsequent to the destruction of their articular cartilages. The head of the femur undergoes absorption from above downwards, becoming flattened and truncated, or disappearing altogether. In the acetabulum the absorption takes place in an upward and backward direction, whereby the socket becomes enlarged and elongated towards the dorsum ilii. To this progressive enlargement of the socket Volkmann gave the suggestive name of "wandering acetabulum" (Fig. 108). The displacement of the femur resulting from these secondary changes is one of the causes of real shortening of the limb.
[Ill.u.s.tration: FIG. 108.--Advanced Tuberculous Disease of Acetabulum with caries and perforation into pelvis.
(Anatomical Museum, University of Edinburgh.)]
#Clinical Features.#--It is customary to describe three stages in the progress of hip disease, but this is arbitrary and only adopted for convenience of description.
_Initial Stage._--At this stage the disease is confined to a focus in the bone which has not yet opened into the joint or to the synovial membrane. The onset is insidious, and if injury is alleged as an exciting cause, some weeks have usually elapsed between the receipt of the injury and the onset of symptoms. The child is brought for advice because he has begun to limp and to complain of pain. There is a history that he has become pale and has ceased to take food well, that his sleep has been disturbed, and that the pain and the limp, after coming and going for a time, have become more p.r.o.nounced. On walking, the affected limb is dragged in such a way as to avoid movement at the hip, and to subst.i.tute for it movement at the lumbo-sacral junction.
The child throws the weight of the trunk as little as possible on to the affected limb, and inclines to rest on the b.a.l.l.s of the toes rather than on the sole. There is usually some wasting of the muscles of the thigh and flattening of the b.u.t.tock. Diminution or loss of the gluteal fold indicates flexion at the hip which might otherwise escape notice. Pain is complained of in the hip, or is referred to the medial side of the knee, in the distribution of the obturator nerve.
Sometimes the pain is confined to the knee, and if the examination is restricted to that joint the disease at the hip may be overlooked. At this stage the att.i.tude of the limb is not constant; at one time it may be natural, and at another slightly flexed and abducted.
Tenderness of the joint may be elicited by pressing either in front or behind the head of the bone, but is of little diagnostic importance.
Pain elicited on driving the head against the acetabulum may occasionally a.s.sist in the recognition of hip disease, but the diagnostic value of this sign has been overrated and, in our opinion, this test should be omitted.
Most information is gained by testing the functions of the joint, and if this is done gently and without jerking, it does not cause pain.
The child should lie on his back, either on his nurse"s knee or on a table; and to rea.s.sure him the movements should be first practised on the sound limb. On slowly flexing the thigh of the affected limb, it will be found that the range of flexion at the hip is soon exhausted, and that any further movement in this direction takes place at the lumbo-sacral junction. The child is next made to lie on his face with the knees flexed in order that the movements of rotation may be tested. The thigh is rotated in both directions, and on comparing the two sides it will be found that rotation is restricted or abolished on the side affected, any apparent rotation taking place at the lumbo-sacral junction. These tests reveal the presence of _rigidity_ resulting from the involuntary contraction of muscles, which is the most reliable sign of hip disease during the initial stage, and they possess the advantage of being universally applicable, even in the case of young children.
_Second Stage._--This probably corresponds with commencing disease of the articular surfaces, and progressive involvement of all the structures of the joint. The child complains more, and usually exhibits the att.i.tude of abduction, eversion, and flexion (Fig. 109).
[Ill.u.s.tration: FIG. 109.--Early Tuberculous Disease of Right Hip-joint in a boy aet. 14, showing flexion, abduction, and apparent lengthening of the limb.]
At first the att.i.tude is maintained entirely by the action of muscles; but when it is prolonged, the muscles, fasciae, and ligaments undergo shortening, so that it becomes fixed.
On looking at the patient, the abnormal att.i.tude may not be at once evident, as he usually restores the parallelism of the limbs by lowering the pelvis on the affected side and adducting the sound limb.
This obliquity or tilting of the pelvis causes _apparent lengthening_ of the diseased limb, and is best demonstrated by drawing one straight line between the anterior iliac spines, and another to meet it from the xiphoid cartilage through the umbilicus; if the pelvis is in its normal position, the two lines intersect at right angles; if it is tilted, the angles at the point of intersection are unequal. The flexion may be largely compensated for by increasing the forward curve of the lumbar spine (lordosis), and by flexing the leg at the knee.
There may also be an attempt to compensate for the eversion of the limb by rotating the pelvis forwards on the affected side.
[Ill.u.s.tration: FIG. 110.--Disease of Left Hip: position of ease a.s.sumed by patient, showing moderate flexion and lordosis.]
[Ill.u.s.tration: FIG. 111.--Disease of Left Hip: disappearance of lordosis on further flexion of the hip.]
To demonstrate the lordosis, the patient should be laid on a flat table; in the resting position the lordosis is moderate, when the hip is flexed it disappears, when it is extended the lordosis is exaggerated, and the hand or closed fist may be inserted between the spine and the table (Fig. 112).
[Ill.u.s.tration: FIG. 112.--Disease of Left Hip: exaggeration of lordosis produced by extending the limb.]
When the functions of the joint are tested, it will be found that there is rigidity, and that both active and pa.s.sive movements take place at the lumbo-sacral junction instead of at the hip. While rigidity is usually absolute as regards rotation, it may sometimes be possible with care and gentleness to obtain some increase of flexion.
For diagnostic purposes most stress should therefore be laid on the presence or absence of rotation.
If the sound limb is flexed at the hip and knee until the lumbar spine is in contact with the table, the real flexion of the diseased hip becomes manifest, and may be roughly measured by observing the angle between the thigh and the table (Fig. 113). This is known as "Thomas"
flexion test," and is founded upon the inability to extend the diseased hip without producing lordosis.
[Ill.u.s.tration: FIG. 113.--Thomas" Flexion Test, showing angle of flexion at diseased (left) hip.]
_Swelling_ is seen on the anterior aspect of the joint; it may fill up the fold of the groin and push forward the femoral vessels. It is doughy and elastic, but may at any time liquefy and form a cold abscess. Swelling about the trochanter and neck of the bone may be estimated by measuring the antero-posterior diameter with callipers, and comparing with the sound side. Swelling on the pelvic aspect of the acetabulum can sometimes be discovered on rectal examination.
_Third Stage._--This probably corresponds with caries of the articular surfaces, since pain is now a prominent feature, and there are usually startings at night. The att.i.tude is one of adduction, inversion, flexion, and apparent or real shortening of the limb (Fig. 114). The _flexion_ is usually so p.r.o.nounced that it can no longer be concealed by lordosis, so that when the patient is rec.u.mbent, although the spine is arched forwards, the limb is still flexed both at the hip and at the knee; with the spine flat on the table, the flexion of the thigh may amount to as much as a right angle. The _adduction_ varies greatly in degree; when it is slight, as is most often the case, the toes of the affected limb rest on the dorsum of the sound foot. When moderate, it is compensated for by raising the pelvis on the affected side, with _apparent shortening_ of the limb, this being the result of an effort on the part of the patient to restore the normal parallelism of the limbs, the sound limb being abducted to the same extent as the affected limb is adducted. It is important to recognise the cause of this shortening, as it can be corrected by treatment. As a result of the obliquity of the pelvis, the patient, when erect, exhibits a lateral curvature of the spine with the dorso-lumbar convexity to the sound side.
[Ill.u.s.tration: FIG. 114.--Tuberculous Disease of Left Hip: third stage, showing adduction and shortening.]
When adduction is p.r.o.nounced, the patient is unable to restore the normal parallelism of the limbs, and the knee on the affected side may cross the sound limb. There is a deep groove at the junction of the perineum and thigh, great prominence of the trochanter, and the pelvis may be tilted to such an extent that the iliac crest comes into contact with the lower ribs.
As a result of the pressure of the carious articular surfaces against one another, the acetabulum is enlarged and the upper end of the femur is drawn gradually upwards and backwards within the socket.
Examination will then reveal the existence of a variable amount of _actual shortening_; it will also be found that the trochanter is displaced above Nelaton"s line, while above and behind the trochanter there is a prominent hard swelling corresponding to the enlarged acetabulum.
There may, therefore, be a combination of real and apparent shortening together amounting to several inches (Fig. 115).
[Ill.u.s.tration: FIG. 115.--Advanced Tuberculous Disease of Left Hip-joint in a girl aet. 14, showing flexion, adduction, shortening, and iliac abscess.]