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PARALLEL MOTION
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PARALLEL See also:MOTION , a See also:form of See also:link-See also:work invented by See also: Paralysis may therefore be divided into three See also:great See also:groups: (I) loss of voluntary power without muscular wasting except from disuse, and without See also:electrical changes in the muscles due to injury or disease of the upper cerebral segment of the motor path of volition; (2) loss of muscular power with wasting and electrical changes in the muscles due to disease or injury of the lower spinal segment formed by the cells of the grey matter of the spinal cord, the anterior roots and the peripheral motor nerves; (3) See also:primary wasting of the muscles. The more common forms of paralysis will now be described. r. Hemiplegia, or paralysis affecting one See also:side of the body, is a frequent result of See also:apoplexy (q.v.); there is loss of motion of the See also:tongue, See also:face, See also:trunk and extremities on the side of the body opposite the See also:lesion in the brain. In a See also:case of severe See also:complete hemiplegia both See also:arm and See also:leg are powerless; the face is paralysed chiefly in the lower part, while the upper part moves almost as well as on the unparalysed side, and the See also:eye can be shut at will, unlike peripheral facial paralysis (See also:Bell's palsy). The tongue when protruded deviates towards the paralysed side, and the muscles of mastication See also:contract equally in ordinary See also:action, although difficulty arises in eating, from See also:food accumulating between the cheek and gums on the paralysed side. Speech is thick and indistinct, and when there is right-sided hemiplegia in a right-handed See also:person, there may be associated various forms of aphasia (q.v.), because the speech centres are in the See also:left hemisphere of the brain. Some muscles are completely paralysed, others are merely weakened, while others, e.g. the trunk muscles, are apparently unaffected. In many cases of even complete hemiplegia, improvement, especially in See also:children, takes See also:place after a few See also:weeks or months, and is generally first indicated by return of movement in the muscles which are habitually associated in their action with those of the opposite unparalysed side; thus, movement of the leg returns first at the See also:hip and See also:knee See also:joints, and of the arm at the See also:shoulder and See also:elbow, although the See also:hand may remain motionless. The recovery however in the See also:majority of cases is only partial, and the sufferer of hemiplegia is left with a permanent weakness of one side of the body, often associated with contracture and rigidity, giving rise to a characteristic gait and attitude. The patient in walking leans to the See also:sound side and swings See also:round the affected leg from the hip, the inner side of the toe of the See also:boot scraping the ground as it is raised and advanced. The arm is adducted at the shoulder, flexed at the elbow, See also:wrist and fingers, and resists all attempts at See also:extension. According to the part of the brain damaged See also:variations of paralytic symptoms may arise; thus occasionallythe paralysis may be limited more or less to the face, the arm or the leg. In such case it is termed a monoplegia, a See also:condition sometimes arising from cerebral See also:tumour. Occasionally the face is paralysed on one side and the arm and leg on the other side ; this condition is termed alternate hemiplegia, which is due to the fact that the disease has damaged the motor path from the brain to the leg and arm before it has crossed over to the opposite side, whereas the path to the face muscles is damaged after it has crossed. In rare cases both leg, arm and face on one side may be paralysed—triplegia; or all four limbs—bilateral hemiplegia. Infantile spastic paralysis, infantile diplegia, or as it is sometimes called Little's disease, is a See also:birth palsy caused by injury from protracted labour, the use of forceps or other causes. The symptoms are generally not observed until See also:long after birth. See also:Convulsions are common, and the See also:child is unable to sit up or walk long after the See also:age at which it should do so. Paraplegia is a See also:term applied to paralysis of the lower extremities; there are many causes, but in the great majority of instances it arises from a See also:local or general disease or injury of the spinal cord. A localized transverse See also:myelitis will interrupt the motor and sensory paths which connect the brain with the spinal grey matter below the lesion, and when the destruction is complete, motor and sensory paralysis in all the structures below the injury results; thus fracture, dislocation and disease of the spinal See also:column (e.g. tubercular See also:caries, syphilitic disease of the membranes, localized tumours and haemorrhages) may cause See also:compression and inflammatory softening, and the result is paralysis of the voluntary muscles, loss of sensation, loss of See also:control over the bowel and See also:bladder, and a great tendency to the development cf See also:bed-sores. The muscles do not See also:waste except from disuse, nor undergo electrical changes unless the disease affects extensively the spinal grey matter or roots as well as the cerebral path. When it does so, as in the case of acute spreading myelitis, the symptoms are usually more severe and the outlook is more See also:grave. In cases of See also:focal myelitis from injury or disease, recovery may take place and the return of power and sensation may occur to such an extent that the patient is able to walk long distances; this happy termination in cases of localized disease or injury of the spinal cord often takes place by keeping the patient on his back in bed, daily practising See also:massage and passive movements, and so managing the case as to avoid bedsores and septic inflammation of the bladder—the two dangerous complications which are liable to arise. 2. Paralysis may result from acute inflammatory affections of the spinal cord involving the grey and See also: In the less severe cases (and they are the most common) only a group of muscles undergo complete paralysis and atrophy, and there is always See also:hope of some return of power in a paralysed limb. Associated with the withered condition of the limb due to the muscular atrophy is an enfeebled circulation, rendering the limb See also:cold, See also:blue and livid; the See also:nutrition of the bones and other parts is involved, so that a limb paralysed in See also:early See also:infancy does not grow and is shorter than its See also:fellow. Deformities arise, some the result of simply failing muscular support; others due to permanent changes in the position of the limbs, for example clubfoot. There is See also:absence of bladder and bowel troubles, and bedsores do not occur; the disease itself is rarely, if ever, fatal. About a See also:month after the onset of the disease local treatment of the atrophied muscles should be commenced, and every effort should be made by massage, by suitable positions and passive movements to promote the circulation and prevent deformities in the affected limbs. Should these See also:measures fail, surgical aid should be sought. Sub-acute and chronic forms of atrophic and spinal paralysis have been described, but some of them were undoubtedly cases of peripheral See also:neuritis. Wasting Palsy. Progressive Muscular Atrophy.—This is a chronic disease characterized by slow and insidious weakness and wasting of groups of muscles due to disease of the anterior spinal grey matter. It begins mostly in adult See also:life between 25 and 45 years of age, and affects See also:males more than See also:females. In the majority of cases it commences in the upper extremities, and the small muscles of the hand are especially liable to be affected. The palmar eminences of the thumb and little See also:finger, owing to the wasting of the muscles, gradually disappear, and a See also:flat See also:ape-like hand is the result; in extreme cases all the small muscles of the hand are atrophied, and a claw-like hand is the result. The muscles which are next most liable to atrophy are those of the shoulder and upper arm, and the atrophy may thence spread to the muscles of the See also:neck and trunk, and the intercostals and even the See also:diaphragm may be affected, causing serious difficulties of respiration. The lower extremities are less often and later affected by wasting. This disease generally runs a slow and progressive course; it may however be years before it spreads from the hand to the arm, and a See also:period of See also:arrest may occur before other muscles become involved. A characteristic feature of the disease is fibrillary twitching of the wasting muscles. The electrical excitability of the muscles is diminished rather than changed, except where the wasting is very extreme, when a partial reaction of degeneration may be obtained. Sensation is unaffected, as the disease is limited to the motor cells of the anterior grey matter (see NEUROPATHOLOGY). There is no affection of the bowel or bladder. See also:Death usually occurs from intercurrent diseases, e.g. See also:bronchitis, See also:pneumonia, or broncho-pneumonia. Some patients See also:die owing to failure of the See also:respiratory muscles; others from the disease spreading to the medulla oblongata (the bulb of the brain) and causing bulbar paralysis. The chronic morbid See also:process leading to decay and destruction of the spinal motor cells which is the essential pathological feature of this disease is generally accompanied, and sometimes preceded, by degeneration of the path of voluntary impulses from the brain. It is then called amyotrophic 'lateral sclerosis, a rapid form of progressive muscular atrophy. Bulbar Paralysis.—A number of different morbid conditions may give rise to a group of symptoms, the See also:principal features of which are paralysis of the muscles concerned in speech, swallowing, phonation and mastication. These symptoms may arise suddenly from vascular lesions or inflammatory processes, which involve the nuclei of origin of the See also:cranial nerves supplyingthe muscles of the tongue, lips, pharynx and larynx.. But there is also a slow degenerative insidious progressive bulbar paralysis affecting both sexes See also:pretty equally; it came on between 40 to 6o years of age, and the cause is unknown. Slight indistinctness of speech, especially in the utterance of consonants requiring the See also:elevation of the tip of the tongue to the dental See also:arch and See also:palate, is usually the first symptom. Later the explosive See also:lip sounds are indistinctly uttered; simultaneously, owing to paralysis of the soft palate, the speech becomes nasal in See also:character and sooner or later, associated with this difficulty of speech, there is a difficulty of swallowing, partly because the tongue is unable to convey the food to the back of the mouth, and it accumulates between the cheeks and gums. Moreover the pharyngeal muscles are unable to seize the food and start the process of swallowing on See also:account of the paralysis of the soft palate; liquids are See also:apt to regurgitate through the nostrils, the patient must therefore be nourished with soft semi-solid food. As the disease proceeds, the difficulty of speech and swallowing is increased by the affection of the laryngeal muscles; the See also:pitch of the See also:voice is lowered and the glottis is imperfectly closed during deglutition; there is consequently a tendency for liquids and food to pass into the larynx and set up fits of coughing, which, however, are ineffectual. Later the muscles of mastication are affected and the disease may extend to the respiratory centre, giving rise to attacks of dyspnoea. The intellectual faculties are as a See also:rule unimpaired, although the facial expression and the curious emotional mobility of the countenance, with a tendency of the patient to burst into tears or See also:laughter, would suggest weak-mindedness. Whilst the lower See also:half of the face is strikingly affected, the upper half retains its normal expression and power of movement. This disease is usually rapidly fatal, since it affects the vital centres, and liability to bronchopneumonia excited by the entrance of food into the See also:air passages is also a See also:constant danger in the later stages. Bulbar Paralysis without Anatomical Change.—This condition is also termed " myasthenia gravis "; it differs from acute and chronic bulbar disease by the absence of muscular atrophy, by normal electrical excitability of the muscles, by a marked development of the paralysis by fatigue, and by considerable remissions of the symptoms. The bulbar symptoms are the most prominent, but all voluntary muscles are more or less affected, especially the eye-muscles. It is a rare disease affecting both sexes equally at almost any age, the causes and See also:pathology of which are unknown. 3. Paralysis resulting from disease or injury of the motor path to the muscles in the peripheral nervous See also:system. Neuritis.—Paralysis may arise in a muscle, a group of muscles, a whole limb, the lower extremities, or there may be a generalized paralysis of voluntary muscles as a result of neuritis. A typical example of neuritis giving rise to paralysis owing to inflammatory swelling and compression is afforded by the facial nerve; this purely motor nerve as it passes out of the See also:skull through a narrow bony passage is easily compressed and its See also:function interfered with, causing a paralysis of the whole of one side of the face and Bell's Palsy. Exposure to a cold See also:draught in a person with rheumatic diathesis is a frequent cause. As an example of See also:simple See also:mechanical compression producing paralysis, crutch Palsy may be cited; it is the result of continuous compression of the musculo-See also:spiral nerve as it winds round the See also:bone of the upper arm. See also:Lead poisoning may give rise to a localized neuritis affecting the posterior inter-osseous nerve, especially in painters and in those whose occupations necessitate excessive use of the extensors of the forearm; the result is wrist drop or lead palsy. See also:Sciatica is a painful inflammatory condition of the sciatic nerve, in which there may be weakness of the muscles; but inability to move the limb is more on account of the See also:pain it causes than on account of paralysis of the muscles. Exposure to cold and wet, e.g. sitting on a See also:damp seat, may lead to sciatica in a gouty or rheumatic person. Multiple neuritis is a painful generalized inflammation of the peripheral nervous system and arises in many toxic conditions of the See also:blood; among the most important are lead, See also:arsenic and chronic See also:alcohol poisoning. It also occurs in See also:diabetes, See also:diphtheria, beri-beri and other conditions (see NEUROPATHOLOGY). A See also:short description of the commonest form will be given. It occurs in chronic alcoholism and especially in See also:women, and is most frequently due to a See also:combination of a septic absorption from some See also:internal disease and the abuse of alcohol. In a marked case the patient may suffer from paraplegia, but it is distinguished from the paraplegia of spinal disease by the fact that there is loss of control of the sphincters only when there is associated dementia, and that instead of the limbs being insensible they are extremely painful on deep pressure. There is wasting of the muscles, and electrical changes in them; frequently there is See also:anaesthesia and analgesia of the skin, which takes a See also:stocking-like distribution. In severe cases the upper limbs may be affected, and all the muscles of the body are more or less liable to be paralysed—even the See also:heart may suffer. The See also:mental condition in such a severe case is usually quite characteristic; there is See also:delirium, the patient is the subject of hallucinations and delusions; there is loss of knowledge of See also:time and place, and illusions of See also:personal identity. A constant symptom is the loss of memory of See also:recent events, while those of early life are easily recollected. Paralyses—termed medically muscular dystrophies—may arise from a primary atrophy of muscle apparently See also:independent of any discoverable change in the nervous system, but due to a congenital developmental defect of the muscles. See also:Heredity plays an important part in the incidence of these diseases, members of the same See also:family being affected with the same type of disease, and at the same period of life. There may be a tendency in a family to the affection of one See also:sex and not the other; on the other hand, children of both sexes may suffer in the same family. It is curious that the majority of cases are males, and that it is transmitted by women who are not themselves its subjects. Many different clinical types have been described based upon the age of onset, the groups of muscles first affected, and the presence or absence of apparent See also:hypertrophy; they are however all varieties of one affection, and in a case where there is an apparent enlargement of muscles there is really atrophy of the contractile muscle fibres and overgrowth of See also:fat and interstitial fibrous See also:tissue; consequently this form of the disease is called pseudo-hyperirophic paralysis. The muscular dystrophies may be divided into two groups according to the period of life in which the malady manifests itself: (r) Those occurring in childhood; (2) those occurring in youth or adult life. In the first group the muscles may be atrophied or apparently hypertrophied. A progressive atrophy of muscles associated with progressive weakness and various disabilities of movement is soon recognized in the relation of cause and effect; but the parents whose first child looks like an See also:infant See also:Hercules, with abnormally large calves and buttocks, cannot for some time appreciate any connexion of this condition with a muscular weakness which is manifested in various ways. The child stands with its feet widely separated; it waddles along rather than walks; it falls easily and rises with difficulty, having to use the hands to push against the See also:floor; it then rests one hand on the knee, and then the other hand on the other knee, and climbs, as it were, up its own thighs in See also:order to assume the erect posture. In this pseudo-hypertrophic form of paralysis the outlook is very grave, and there is little hope of the patient reaching adult life. Paralysis agitans, Shaking Palsy or See also:Parkinson's Disease is a chronic progressive disease of the nervous system occurring See also:late in life, and characterized by weakness,. tremors and stiffness of the muscles associated with a See also:peculiar attitude and gait. The first sign of the disease is weakness followed by tremor of one hand; this consists of continuous movements of the thumb and forefinger as in See also:rolling a pill, or of movements of the hand like beating a tom-tom; then the other hand is affected, and later there is tremor at the See also:ankle. In some cases there is a continual nodding movement of the head. These tremors are at the See also:rate of five per second and cease during See also:sleep. The attitude and gait are very characteristic; the head is See also:bent forward, and the patient in beginning to walk takes slow steps, which soon become short and See also:quick as if he were See also:running after his centre of gravity. The See also:intellect is clear and in marked contrast to the See also:mask-like expression. This disease lasts for years, and but little can be done ih the way of treatment, except passive movements of the limb to prevent contracture. Treatment.—T here are certain general principles in the treatment of all forms of paralysis which may be summarized as follows. 1. See also:Rest in bed and See also:attention to the vital functions of the body, the heart's action, the respiratory functions, nutrition and See also:excretion. The See also:pulse is the best See also:guide to the See also:administration of drugs and stimulants. As regards the respiratory function, one of the dangers of paralysis is an intercurrent pneumonia—sometimes unavoidable, often due, however, to attempts to give nourishment to a patient in an insensible See also:state, with the result that some of the fluid enters the bronchial tubes, when either the reflex protective coughing is not excited or is ineffectual. Attention to the bowels and bladder is most important. A purge at the onset of paralysis is indicated when the pulse is full and of high tension, and the See also:regular action of the bowels is necessary in all conditions. Retention of urine should be carefully avoided, if necessary by the passing of a catheter, but too much emphasis cannot be laid upon the importance of adopting aseptic precautions to avoid infection of the bladder. Daily inspection of the back should be made of all paralysed patients, and precautions taken to keep the skin of all parts exposed to pressure clean; the back should be laved with eau-de-See also:Cologne or spirit to harden the skin. Any sign of a red spot on the back or buttock of the paralysed side should be a warning See also:note of the possibility of a See also:bedsore; See also:zinc See also:powder or ointment should be applied and the effect of pressure on the part be removed if possible by change of posture and by the use of a See also:water-bed. It is important to See also:cover all warm bottles with See also:flannel, for owing to insensibility large blisters, which heal with difficulty, may result. In cases of paraplegia the legs should be covered with warm woollen hand-knitted stockings, and a See also:cradle employed to protect the feet from the continuous See also:weight of the bed-clothes, a fruitful source of See also:foot drop. 2. As soon as the acute symptoms have passed off passive movement and massage may be employed with See also:advantage; in some cases electrical treatment is indicated; but as a rule, especially in children, electrical treatment offers the disadvantage of being painful and not accomplishing more than can be effected by massage and passive movements. When the passive movements are being made the patient should be instructed by the operator to will the movement which he is performing, and thus try to re-establish the connexion of the brain with the muscles through the point of interruption or by a new path if that is not possible. (F. W. Additional information and CommentsThere are no comments yet for this article.
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