_Later symptoms_ are the result of descending degeneration taking place in the antero-lateral columns of the cord. There are often violent and painful jerkings of the muscles of the limbs; the muscles become rigid and the limbs flexed.
_Treatment._--When the cord is completely divided, no benefit can follow operative interference, and treatment is directed towards the prevention of infective complications from cyst.i.tis and bed-sores.
#Injuries of the Cord at Different Levels.#--_Cervical Region._--Complete lesions of the _first four cervical segments_--that is, above the level of the disc between the third and fourth cervical vertebrae--are always rapidly, if not instantaneously, fatal, as respiration is at once arrested by the destruction of the fibres which go to form the phrenic nerve. It is from this cause that death results in judicial hanging.
In lesions between the _fifth cervical and first thoracic segments inclusive_, all four limbs are paralysed. Sensation is lost below the second intercostal s.p.a.ce. The parts above this level retain sensation, as they are supplied by the supra-clavicular nerves which are derived from the fourth cervical segment (Fig. 205). Recession of the eyeb.a.l.l.s, narrowing of the palpebral fissures, and contraction of the pupils result from paralysis of the cervical sympathetic. Respiration is almost exclusively carried on by the diaphragm, and hiccup is often persistent. There is at first retention of urine, followed by dribbling from overflow, and sugar is sometimes found in the urine.
Priapism is common. The pulse is slow (40 to 50) and full; and the temperature often rises very high--a symptom which is always of grave omen.
[Ill.u.s.tration: FIG. 205.--Distribution of the Segments of the Spinal Cord.
(After Kocher.)]
When the lesion is confined to the _sixth cervical segment_, the arms a.s.sume a characteristic att.i.tude as a result of the contraction of the muscles supplied from the higher segments. The upper arm is abducted and rotated out, the elbow is sharply flexed, and the hand supinated and flexed (Fig. 206). Sensation is retained along the radial side of the limb.
[Ill.u.s.tration: FIG. 206.--Att.i.tude of Upper Extremities in Traumatic Lesions of the Sixth Cervical Segment. The prominence of the abdomen is due to gaseous distension of the bowel.]
Total lesions of the lower cervical segments are usually fatal in from two to three days to as many weeks, from embarra.s.sment of respiration and hypostatic pneumonia.
When the lesion is confined to _the first thoracic segment_, the att.i.tude of the arms is usually that of slight abduction at the shoulder and flexion at the elbow, the forearms lie semi-p.r.o.nated on the chest or belly, and there is slight flexion of the fingers. There is complete anaesthesia as high as the level of the second inters.p.a.ce, and along the distribution of the ulnar nerve (Fig. 205); the respiration is entirely diaphragmatic; and the ocular changes depending on paralysis of the cervical sympathetic are present.
_Thoracic Region._--In injuries of the thoracic region--second to eleventh thoracic segments inclusive--the anaesthesia below the level of the lesion is complete and its upper limit runs horizontally round the body, and not parallel with the intercostal nerves. Above the anaesthetic area there is a zone of hyperaesthesia, and the patient complains of a sensation as if a band were tightly tied round the body--"girdle-pain."
The motor paralysis and the anaesthesia are co-extensive. The intercostal muscles below the seat of the lesion and the abdominal muscles are paralysed. The respiratory movements are thus impeded, and, as the patient is unable to cough, mucus gathers in the air-pa.s.sages and there is a tendency to broncho-pneumonia. As the patient is unable to aid defecation or to expel flatus by straining, the bowel is liable to become distended with faeces and gas, and the meteorism which results adds to the embarra.s.sment of respiration by pressing on the diaphragm. There is retention of urine followed by dribbling from overflow. As the reflex arc is intact there may be involuntary and unconscious micturition whenever the bladder fills.
If infection of the bladder and the formation of bed-sores are prevented, the patient may live for months or even for years. At any time, however, infection of the bladder may occur and spread to the kidneys, setting up a pyelo-nephritis; or the patient may develop an ascending myelitis, and these conditions are the most common causes of death.
_Lumbo-sacral Region._--All the spinal segments representing the lumbar, sacral, and coccygeal nerves lie between the level of the eleventh thoracic and first lumbar vertebrae. Injuries of the lower thoracic and upper lumbar vertebrae, therefore, may produce complete paralysis within the area of distribution of the lumbar and sacral plexuses. The anaesthesia reaches to about the level of the umbilicus.
There is incontinence of urine and faeces from the first. Priapism is absent. Bed-sores and other trophic changes are common, and there is the usual risk of complications in relation to the urinary tract.
_Conus Medullaris._--A lesion confined to the conus medullaris may result from a fall in the sitting position. It is attended with slight weakness of the legs, anaesthesia involving a saddle-shaped area over the b.u.t.tocks and back of the thighs, the perineum, s.c.r.o.t.u.m, and p.e.n.i.s.
The urethra and a.n.a.l ca.n.a.l are insensitive, and there is paralysis of the levatores ani, the rectal and the vesical sphincters. The testes retain their sensation.
_Cauda Equina._--As the cord terminates opposite the lower border of the first lumbar vertebra, injuries below this level implicate the cauda equina. The extent of the motor and sensory paralysis varies with the level of the lesion and with the particular nerves injured.
Sometimes it is complete, sometimes, selective. As a rule all the muscles of the lower extremity are paralysed, except those supplied by the femoral (anterior crural), obturator, and superior gluteal nerves.
The perineal and penile muscles are also implicated. There is anaesthesia of the p.e.n.i.s, s.c.r.o.t.u.m, perineum, lower half of the b.u.t.tock, and the entire lower extremity, except the front and lateral aspects of the thigh, which are supplied by the lateral cutaneous nerve and the cutaneous branches of the femoral (anterior crural). There is incontinence of urine and faeces. The prognosis is more favourable than in lesions affecting the cord itself, and the only risk to life is the occurrence of infective complications.
#Partial Lesions of the Cord and Nerve Roots.#--Partial lesions, such as bruises, lacerations, or incomplete ruptures, are always attended with haemorrhage into the substance of the cord, and usually result from distortions or incomplete fractures and dislocations of the spine, or from bullet wounds. They are comparatively rare.
When the _nerve roots_ alone are injured, sensory phenomena predominate. Formication, radiating pains, and neuralgia are present in the area of distribution of the nerves implicated. There is motor paresis or paralysis, which may disappear either suddenly or gradually, or may persist and be followed by atrophy of the muscles concerned. In contrast to what is observed from pressure by tumours and inflammatory products, twitchings and cramps are rare.
In _partial lesions of the cord_ the motor phenomena predominate.
Paresis extends to the whole of the motor area below the seat of the lesion, but the weakness is more marked on one side of the body. The distal parts--feet and legs--suffer more than the proximal--arms and hands, and the extensors more than the flexors. The paresis develops slowly, varies in extent and degree, and may soon improve. Vaso-motor disturbances accompany the motor symptoms. Irritative phenomena, such as twitchings or contractures, may come on later.
The deep reflexes, particularly the knee-jerks, may be absent at first, but they soon return, and are usually exaggerated; a well-marked Babinski response may appear later. Abolition of the reflexes, therefore, does not necessarily indicate complete destruction of the cord, but their return is conclusive evidence that the lesion is a partial one. It is necessary, therefore, to defer judgment until it is determined whether the abolition of the reflexes is temporary or permanent.
Sensory disturbances may be entirely absent. When present, they are incomplete, and are chiefly irritative in character. They may not reach the same level as the motor phenomena, and the different sensory functions are unequally disturbed in the areas corresponding to the several nerve roots. There is sometimes a combination of hyperaesthesia on one side and anaesthesia on the other.
Retention of urine is not always present even in those cases in which the limbs are completely paralysed, as the fibres of one side of the cord are sufficient to maintain the functions of the bladder. The patient may be aware that the bladder is full, although he is unable to empty it. Similarly, sensation in the r.e.c.t.u.m and a.n.u.s may be retained although the control of the sphincters is lost. Priapism may be present, but tends to disappear.
In partial lesions, the difficulties of diagnosis are sometimes increased by the occurrence of haemorrhage into the substance of the cord, so that symptoms of generalised pressure are superadded to those of the partial lesion. In time the symptoms due to the intra-medullary haemorrhage pa.s.s off, but those due to the tearing of the cord persist.
The _prognosis_ is generally favourable, but must be guarded, as permanent organic changes in the cord may take place, causing a spastic condition of the muscles. When recovery is taking place the first signs are the return of the knee-jerks, and a gradual change in the limbs from the flaccid to the spastic condition. Sensibility returns in the order--touch, pain, temperature, and the parts supplied by the lowest sacral segments usually become sentient first. Voluntary power returns earlier in the flexors than in the extensors, and flexion of the toes is almost invariably the earliest voluntary movement possible. Infection from bed-sores or from the urinary tract is the most common cause of death in cases that terminate fatally.
The _treatment_ is carried out on the same lines as for total lesions.
Laminectomy, however, is indicated when there is reason to believe that the pressure is due to some cause, such as a blood-clot or a displaced fragment of bone, which is capable of being removed.
In practice when a person has lost the power of the lower extremities as the result of an accident, there are three conditions requiring ultimate differentiation--a concussion of the cord alone, a total transverse lesion and a partial lesion of the cord together with concussion. It must again be emphasised that it may not be possible to differentiate between these immediately after the accident. Two or three days may elapse before it is possible to give a definite opinion.
"#Railway Spine.#"--This term is employed to indicate a disturbance of the nervous system which may develop in persons who have been in railway accidents, but a similar group of symptoms is met with in men engaged in laborious occupations such as coal-miners, who, after an injury to the back, develop symptoms referable to the nervous system on account of which they claim compensation not infrequently in the law-courts. It is a remarkable fact that it seldom occurs in railway employees, or in pa.s.sengers who sustain gross injuries, such as fractures or lacerated wounds.
_Clinical Features._--The patient usually gives a history of having been forcibly thrown backwards and forwards across the carriage at the time of the accident. He is dazed for a moment and suffers from shock or, it may be, is little the worse at the time, and is able to continue his journey. On reaching his destination, however, he feels weak and nervous, and complains of pain in his back and limbs. There is rarely any sign of local injury. For a few days he may be able to attend to business, but eventually feels unfit, and has to give it up.
The symptoms that subsequently develop are for the most part subjective, and it is difficult therefore either to corroborate or to refute them; it will be observed that while some of them are referable to the cord the greater number are referable to the brain. They usually include a feeling of general weakness, nervousness, and inability to concentrate the attention on work or on business matters.
The patient is sleepless, or his sleep is disturbed by terrifying dreams. His memory is defective, or rather selective, as he can usually recall the circ.u.mstances of the accident with clearness and accuracy. He becomes irritable and emotional, complains of sensations of weight or fullness in the head, of temporary giddiness, is hypersensitive to sounds, and sometimes complains of noises in the ears. There are weakness of vision and photophobia, but there are no ophthalmoscopic changes. He has pain in the back on making any movement, and there is a diffuse tenderness or hyperaesthesia along the spine. There is weakness of the limbs, sometimes attended with numbness, and he is easily fatigued by walking. There may be loss of s.e.xual power and irritability of the bladder, but there is seldom any difficulty in pa.s.sing urine. The patient tends to lose weight, and may acquire an anxious, careworn expression, and appear prematurely aged.
Special attention should be directed to the condition of the deep reflexes and to the state of the muscles, as any alteration in the reflexes or atrophy of the muscles indicates that some definite organic lesion is present.
As the symptoms are so entirely subjective, it is often extremely difficult to exclude the possibility of malingering; it is essential that the patient should be examined with scrupulous accuracy at regular intervals and careful notes made for purposes of comparison, and also that the doctor should retain an impartial att.i.tude and not develop a bias either in favour of or against the patient"s claim for compensation.
So long as litigation is pending the patient derives little benefit from treatment, but after his mind is relieved by the settlement of his claim--whether favourable to him or not--his health is usually restored by the general tonic treatment employed for neurasthenia.
INJURIES OF THE VERTEBRAL COLUMN
_Partial_ lesions include twists or sprains, isolated dislocations of articular processes, isolated fractures of the arches and spinous processes, and isolated fractures of the vertebral bodies. The most important _complete_ lesions are total dislocations and fracture-dislocations.
In partial lesions, the continuity of the column as a whole is not broken, and the cord sustains little damage, or may entirely escape; in complete lesions, on the other hand, the column is broken and the cord is always severely, and often irreparably, damaged.
Twists and dislocations are most common in the cervical region, that is, in the part of the spine where the forward range of movement--flexion--is greatest. Fractures are most common in the lumbar region, where flexion is most restricted. Fracture-dislocations usually occur where the range of flexion is intermediate, that is, in the thoracic region.
In all lesions accompanied by displacement, the upper segment of the spine is displaced forwards.
#Twists# or #sprains# are produced by movements that suddenly put the ligamentous and muscular structures of the spine on the stretch--in other words, by lesser degrees of the same forms of violence as produce dislocation. When the interspinous and muscular attachments alone are torn, the effects are confined to the site of these structures, but when the ligamenta flava are involved, blood may be extravasated and infiltrate the s.p.a.ce between the dura and the bone and give rise to symptoms of pressure on the cord. The nerve roots emerging in relation to the affected vertebrae may be stretched or lacerated, and as a result radiating pains may be felt in the area of their distribution.
In the _cervical_ region, distortion usually results either from forcible extension of the neck--for example from a violent blow or fall on the forehead forcing the head backwards--or from forcible flexion of the neck. The patient complains of severe pain in the neck, and inability to move the head, which is often rigidly held in the position of wry-neck. There is marked tenderness on attempting to carry out pa.s.sive movements, and on making pressure over the affected vertebrae or on the top of the head. The maximum point of tenderness indicates the vertebra most implicated. In diagnosis, fracture and dislocation are excluded by the absence of any alteration in the relative positions of the bony points, and by the fact that pa.s.sive movements, although painful, are possible in all directions.
In the _lumbar_ region sprains are usually due to over-exertion in lifting heavy weights, or to the patient having been suddenly thrown backwards and forwards in a railway collision. The attachments of the muscles of the loins are probably the parts most affected. The back is kept rigid, and there is pain on movement, particularly on rising from the stooping posture.
_Treatment._--Unless carefully treated, a sprain of the spine is liable to cause prolonged disablement. The patient should be kept at rest in bed, and, when the injury is in the cervical region, extension should be applied to the head with the nape of the neck supported on a roller-pillow. Early recourse should be had to ma.s.sage, but active movements are forbidden till all acute symptoms have disappeared. In patients predisposed to tuberculosis, the period of complete rest should be materially prolonged.
#Isolated Dislocation of Articular Processes.#--This injury, which is most frequently met with in the cervical region and is nearly always unilateral, is commonly produced by the patient falling from a vehicle which suddenly starts, and landing on the head or shoulders in such a way that the neck is forcibly flexed and twisted. The articular process of the upper vertebra pa.s.ses forward, so that it comes to lie in front of the one below.
The pain and tenderness are much less marked than in a simple twist, as the ligaments are completely torn and are therefore not in a state of tension. The patient often thinks lightly of the condition at the time of the accident, and may only apply for advice some time after on account of the deformity. The head is flexed and the face turned towards the side opposite the dislocation, the att.i.tude closely resembling that of ordinary wry-neck, only it is the opposite sterno-mastoid that is tight. The bony displacement is best recognised by palpating the transverse process of the dislocated vertebra. In the case of the upper vertebrae this is done from the pharynx, in the lower between the sterno-mastoid and the trachea. There is pain on attempting movement, and tenderness on pressure, particularly on the side that is not displaced, as the ligaments there are on the stretch.
There are often radiating pains along the line of the nerves emerging between the affected vertebrae. As the bodies are not separated, damage to the cord is exceptional. The lesion can usually be recognised in a radiogram.
_Treatment._--Reduction should be attempted at once, before the vertebrae become fixed in their abnormal position. Under anaesthesia gentle extension is made on the head by an a.s.sistant, and the abnormal att.i.tude is first slightly exaggerated to relax the ligaments and to restore mobility to the locked articular processes. The head is then forcibly flexed towards the opposite side, after which it can be rotated into its normal att.i.tude (Kocher). Haphazard movements to effect reduction are attended with risk of damaging the cord. After reduction has been effected, the treatment is the same as that of a sprain.
#Isolated Fractures of the Arches, Spinous and Transverse Processes.#--Fractures of the arches and spinous processes usually result from direct violence, such as a blow or a bullet wound, and are accompanied by bruising of the overlying soft parts, irregularity in the line of the spines, and by the ordinary signs of fracture.
Skiagrams are useful in showing the exact nature of the lesion. These fractures are most common in the lower cervical and in the thoracic regions, where the spines are most prominent and therefore most exposed to injury.