The deformities induced by gout, rheumatism, and rheumatoid arthritis fall more directly within the domain of the physician, while those due to tuberculous or traumatic lesions are of more immediate concern to the surgeon, but the characters which distinguish the various conditions from each other are of interest for every practitioner. The chief points bearing upon diagnosis are as follows: In the gouty form the personal and family history of the patient, the acute and painful nature of the local inflammatory attacks, the presence of urate of soda deposits in the part, and the evidence of similar disease in other portions of the body. In chronic rheumatism, which is more often present in women and in the poorer classes, the moderately painful attacks of synovitis with crepitation, and evidence of wearing away of cartilage. In chronic rheumatoid arthritis the presence of bony outgrowths around the margin of the articulation is the main element of distinction from the latter condition. In tuberculous disease the personal and family history, the soft fusiform swelling, the tendency to breaking down of the morbid tissue, and the more or less complete destruction of the articular capsule in the later stages. Contractions with ankylosis may also occur in acute rheumatism and acute rheumatoid arthritis, and in a peculiar neuropathic condition simulating the latter. These will be referred to in connection with the contractions of the toes. In the traumatic forms the history and marks of injury will usually be sufficient for diagnosis; but it must, of course, be understood that common injuries, by weakening the resistance of the part, may localise the attack of a specific disease, such as tuberculosis or gout, and hence the onset of tubercular or gouty arthritis may coincide with an ordinary traumatism. It is, as a rule, only in the tuberculous and traumatic forms that the surgeon is consulted. The treatment must, of course, be based on general principles; but it is necessary to recollect that an ankylosed finger-joint nearly always renders the digit worse than useless, especially if the articulation be fixed in the position of extension.
It is only necessary to mention that contractions without joint lesion may occur in the fingers as a result of disease or injury of the bone. Simple fracture in the neighbourhood of an articulation may produce a deformity closely resembling that of dislocation. Caries or necrosis may also lead to a breach of continuity in the shaft of a bone, and various distortions may follow the cure of the disease.
CONTRACTIONS OF PARALYTIC AND SPASTIC ORIGIN FOLLOWING LOCAL INJURY.
A complete account of the various conditions falling under this denomination would require an entire course of lectures, and it is hence necessary to confine our attention to those forms which belong to the surgeon rather than to the physician.
Spastic conditions following local injury are very rare. An example was brought before the Medical Society by Dr. Beevor[6] in April 1888, in which a contusion of the right hand in a boy of fifteen was followed five days later by permanent contraction of the hand with total anæsthesia as far as the shoulder and loss of the muscular sense, the movements of the arm and forearm remaining unimpaired. In the discussion a similar case was referred to by Dr. Hadden.
All the nerves which govern the muscles acting upon the fingers are liable to injury—the median and ulnar more particularly by wounds, usually in the wrist, and the musculo-spiral by pressure of a crutch.
An injury involving solution of continuity of the Ulnar nerve is a very grave accident, unless it can be treated surgically without any long delay. The symptoms are such as might be inferred from a knowledge of the distribution of the branches. It will be remembered that the nerve supplies the flexor carpi ulnaris and ulnar half of the flexor profundus digitorum in the forearm, the whole of the muscles of the hand, except the abductor, opponens, and outer head of the flexor brevis pollicis, and the two inner lumbricales, and it gives sensation to the skin over the inner side of the wrist and hand, to the palmar and dorsal surfaces of the little and ulnar half of the ring finger, and sometimes also to the radial half of the ring finger and ulnar half of the middle finger. The effects of the nerve lesion will, of course, vary with the position of the injury. If the trunk be divided just above the wrist, the branches to the two forearm muscles and the cutaneous branch to the back of the hand and fingers will be spared; but the palmar cutaneous filament will probably be implicated by the wound. The paralysis of the interossei produces an inability to flex the first phalanges and extend the second and third, while the unbalanced action of the extensor, and superficial and deep flexors, causes the position of super-extension of the metacarpo-phalangeal joint with flexion of the inter-phalangeal joints, which constitutes the main en griffe of French pathologists ([Fig. 9]). The clawing is chiefly marked in the ring and little digits, especially the latter, but is lessened in the index and middle fingers by the continued integrity of the first and second lumbricales. There is, in addition, great loss of power in flexion and adduction of the thumb, and complete loss of sensation over the front and distal part of the back of the little finger and the corresponding portion of the ulnar side of the ring finger. At a later stage nutritive changes appear in the paralysed structures, and the deformity becomes complicated by the atrophy of the skin and subcutaneous fat, the hollowing of the interosseous spaces and the wasting of the thenar and hypothenar eminences. If the nerve be injured at the elbow, the paralysis of the two forearm muscles, and the loss of sensation over the ulnar side of the back of the hand would add to the symptoms, but would not sensibly affect the deformity.
Fig. 9.
Deformity in case of wound of ulnar nerve above wrist.