Manual of Surgery Volume II Part 48

_Treatment._--The more severe forms of spina bifida only call for palliative treatment, which consists in protecting the protrusion against infection and applying a sterilised dressing and a supporting bandage. A meningocele may be tapped with a fine needle pa.s.sed through healthy skin, and the empty sac compressed by a pad of wool and an elastic bandage.

Operative treatment is seldom to be recommended in a young child unless it is otherwise viable and the swelling is increasing rapidly and threatening to burst, and there is reason to believe that the paralysis is due to pressure. The immediate results of operation are usually satisfactory, but in a large proportion of cases the child subsequently develops hydrocephalus, from which it ultimately succ.u.mbs. The hope of improvement in the motor symptoms after operation depends on the site of the spina bifida; above the twelfth thoracic vertebra there is no prospect of improvement; below this level, inasmuch as it is the tip of the conus or the cauda equina that is involved, there may be regeneration of nerve fibres and return of power in the lower extremities, and control of the sphincters may be regained. Murphy has practised resection of cicatricial or atrophied portions of the cauda, with end-to-end suture.

The term #spina bifida occulta# is applied to a condition in which there is no protrusion of the contents of the vertebral ca.n.a.l, although the vertebral arches are deficient. The skin over the gap is often puckered and adherent, and is frequently covered with a growth of coa.r.s.e hair.

A ma.s.s of fat may project towards the surface, and when situated in the lumbo-sacral region may suggest a caudal appendage or tail (Fig.

222).

[Ill.u.s.tration: FIG. 222.--Tail-like Appendage over Spina Bifida Occulta in a boy aet. 5, and a.s.sociated with incontinence of urine.

Operation was followed by temporary retention.]

The clinical importance of spina bifida occulta lies in the fact that it is sometimes a.s.sociated with congenital club-foot, and with nerve symptoms, in the form of sensory, motor, and trophic disturbances referable to the lower limbs, such as perforating ulcer, and to the sphincters. These nerve symptoms usually result from the presence of a tough cord composed of connective tissue, fat, and muscle, stretching from the skin through the vertebral ca.n.a.l to the lower end of the spinal cord. As this strand of tissue does not grow in proportion with the body, in the course of years it drags the cord against the lower border of the membrana reuniens, which closes in the vertebral ca.n.a.l posteriorly. These symptoms may be relieved by the removal of this strand of tissue from the gap in the vertebral arches, or by incising the membrana reuniens.

#Congenital Sacro-coccygeal Tumours--Teratoma.#--Many varieties of congenital tumours are met with in the region of the sacrum and coccyx. The majority are developed in relation to the communication which exists in the embryo between the neural ca.n.a.l and the alimentary tract--the post-a.n.a.l gut or neurenteric ca.n.a.l. Some are evidently of bigerminal origin, and contain parts of organs, such as limbs, partly or wholly formed, nerves, parts of eyes, mammary, renal, and other tissues.

Among other tumours met with in this region may be mentioned: the congenital _lipoma_--a small, rounded, fatty tumour which often suggests a caudal appendage (Fig. 222); the _sacral hygroma_, which forms a sessile cystic tumour growing over the back of the sacrum, and is believed to be a meningocele which has become cut off _in utero_ by the continued growth of the vertebral arch; dermoids, sarcoma, and lymphangioma.

[Ill.u.s.tration: FIG. 223.--Congenital Sacro-coccygeal Tumour.

(Photograph lent by Sir George T. Beatson.)]

The _treatment_ consists in removing the tumour, as from its situation it is exposed to injury, and this is liable to be followed by infection. From the position of the wound, and the fact that many of these tumours extend into the hollow of the sacrum and therefore necessitate an extensive dissection, there is considerable risk from infection, especially in young children. The risk is increased when the tumour communicates with the vertebral ca.n.a.l.

#Congenital Sacro-coccygeal Sinuses and Fistulae.#--The _post-a.n.a.l dimple_, a shallow depression frequently observed over the tip of the coccyx, may be due to traction exerted on the skin at this spot by the remains of the neurenteric ca.n.a.l, or by the caudal ligament of Luschka. Sometimes the integument is retracted to such an extent that one or more _sinuses_ are formed, lined with skin which is furnished with hairs, sweat, and sebaceous glands. The bursting of a dermoid, or its being incised in mistake for an abscess, may result in the formation of such a sinus, which fails to heal and may persist for years.

In some cases the depression communicates with the vertebral ca.n.a.l, const.i.tuting a complete _sacro-coccygeal fistula_, which may be lined with cylindrical or ciliated epithelium.

From the acc.u.mulation of secretions and subsequent infection, these conditions may be a.s.sociated with a persistent offensive discharge, and they are liable to be mistaken for ano-rectal fistulae. They are best dealt with by complete excision, and as primary union cannot be expected, the wound should be treated by the open method.

CHAPTER XVIII

DEVIATIONS OF THE VERTEBRAL COLUMN

LORDOSIS--KYPHOSIS--SCOLIOSIS

Three main deviations of the vertebral column are described: _Lordosis_, in which it is unduly arched forwards; _Kyphosis_, in which it is unduly arched backwards; and _Scoliosis_ or lateral deviations, in which the spine deviates to one side of the middle line.

#Lordosis# or _anterior curvature of the spine_ with the convexity forwards, is chiefly met with in the lumbar region as an exaggeration of the natural curvature. A minor degree of lordosis sometimes occurs as a peculiarity in the conformation of the individual and may be present in several members of the same family; also in street-hawkers and others who carry weights suspended in front of them; in very obese persons; in those who suffer from large abdominal tumours, such as fibroids; and in pregnant women. In its more marked and typical forms it is met with as a compensatory deviation when the pelvis is tilted forwards in a.s.sociation with flexion of one or of both hip-joints.

Ill.u.s.trations of this a.s.sociation are found in congenital dislocation of the hip, particularly when this is bilateral, in tuberculous disease of the hip when recovery has occurred with ankylosis in the flexed position, and in Charcot's disease of the hip. The resuming of the erect position with tilting of the pelvis from flexion at the hip is necessarily attended by an exaggeration of the forward curvature of the lumbar spine. Its relations.h.i.+p to the erect posture is readily demonstrated by noting its partial or complete disappearance when the patient is sitting and the tilting of the pelvis is thus eliminated.

Lordosis elsewhere than in the lumbar segment is met with as a compensatory deviation to kyphotic or backward curvature of the spine: in Fig. 211, for example, a kyphotic projection in the mid-thoracic region has led to a lordosis in the cervico-thoracic segment above, and in the thoracico-lumbar segment below, the forward curve being again a necessary outcome of the resuming of the erect posture. The absence of a compensatory lordosis in such a condition would warrant the inference that the patient had been bed-ridden.

#Kyphosis# or _posterior curvature of the spine_ with the convexity backwards, is met with at all periods of life, and results from a wide range of conditions.

In infancy it is a common result of _general debility_. The child need not appear to be badly nourished, it may even be fat and look well, but there is a want of muscular vigour such as should enable it to hold itself erect in the sitting posture. It is to be noted that a considerable degree of kyphosis may exist without interference with the normal outlook in the erect posture, and, therefore, the question of compensatory curvature does not arise. In the adolescent a degree of kyphosis in the cervico-thoracic region is common, and is spoken of as "round shoulders"; it is largely a matter of habit that requires correction by the governess or nurse. Among agricultural labourers and gardeners after middle life, and in the aged, this type of curvature is of common occurrence and is evidently a.s.sociated with their occupation. An exaggerated form of the same cervico-thoracic kyphosis is met with in patients suffering from progressive muscular atrophy, poliomyelitis, osteitis deformans of Paget, acromegaly, and many allied conditions in which either the muscular or the mental vigour is deficient, and the patient adopts the cervico-thoracic kyphosis as the att.i.tude of rest.

Another type of diffuse kyphosis without compensatory curvature is met with in _arthritis deformans_, in which the kyphosis is a.s.sociated with the disappearance of the intervertebral discs and ankylosis of the vertebral bodies by bridges of new bone in the position of the anterior common ligament.

_Partial or localised kyphosis_, on the other hand, is the result of organic changes in the bodies of the vertebrae of the segment of spine affected. It is most often met with in Pott's disease in which the extent of the curve depends on the number of bodies affected, and its degree on the amount of destruction that the bodies have undergone.

With the resumption of the erect posture, and in order that the eyes should look directly forwards, a compensatory lordosis is acquired above and below the segment that is the seat of kyphosis (Fig. 211). A similar but less marked type of kyphosis may follow upon compression fracture of the spine--in the condition known as traumatic spondylitis; and as a result of other lesions, such as osteomalacia, or malignant disease, in which the bodies undergo softening and yield, so that the spinous processes project posteriorly.

SCOLIOSIS

#Scoliosis# or _lateral curvature_ is by far the commonest and most important deviation of the spine. The student will obtain a clearer conception of the nature of this deformity if we consider in the first place those types for which an obvious explanation is available.

_Static scoliosis_, for example, when one leg is shorter than the other, the pelvis is tilted down on the short side, the thoracico-lumbar spine deviates laterally to the normal side, and to restore the equilibrium of the trunk the cervico-thoracic spine deviates again in the opposite direction. The causes of one leg being shorter than the other are numerous and varied; they include such conditions as unilateral congenital dislocation of the hip, fractures united with overriding of the fragments, diseases of the joints, _e.g._, hip disease, or of the bones, especially such as interfere with the function of ossifying junctions; and acquired deformities such as unilateral flat-foot, knock-knee, or bow-leg. Clinically, this type of scoliosis is identified by observing that when the patient sits down the deviation of the spine disappears; it is relieved or got rid of by raising the sole and the heel of the boot on the short side, and, if required, by inserting an "elevator" inside the boot.

When there is _shortening of the muscles on one side of the trunk_ there develops a lateral curvature of the spine with its convexity to the normal side; a good example of this is afforded in cases of infantile hemiplegia (Fig. 224) in which the deviation affects the entire column: a localised form is seen in congenital wry-neck, in which the convexity of the cervico-dorsal curve is on the side of the normal sterno-mastoid with a compensatory deviation to the opposite side in the spine below (Fig. 272). _Unilateral paralysis_ of _muscles_ acting on the trunk may also cause a lateral deviation of the spine, as is well seen in paralysis of the trapezius, which results in a cervical scoliosis with the convexity to the non-paralysed side.

[Ill.u.s.tration: FIG. 224.--Scoliosis following upon Poliomyelitis affecting right arm and leg.

(Mr. D. M. Greig's case.)]

_Asymmetry of the thorax_, such as may follow on empyema with defective expansion of the lung, causes a lateral deviation of the dorsal spine with the convexity towards the normal side.

_Att.i.tudes_ adopted to relieve pain, such as that caused by sciatica, sacro-iliac or hip disease, in which the weight of the body is transferred to the normal side, cause a scoliosis similar to that due to irregularity in the length of the lower extremities, and is similarly made to disappear when the patient sits upon a flat surface.

_Malformation_ or _disease of the vertebrae_ themselves is a well recognised cause of scoliosis; the best known, as it may be also the most severe and the most intractable, is that due to rickets, under which heading it has already been described (Fig. 225). In a few cases a rudimentary wedge-shaped vertebra has been revealed by the X-rays.

[Ill.u.s.tration: FIG. 225.--Rickety Scoliosis in a child aet. 2.]

In all of these forms or types of scoliosis the primary cause must be searched for and when found is made the first object of treatment; the treatment of the scoliosis as such is on the same lines as in the postural variety that now falls to be described.

#Habitual or Postural Scoliosis.#--These names have been given to the type of scoliosis that develops in young girls and for which there is no mechanical explanation.

It is most frequently met with in rapidly growing girls of poor physique who are overworked at school or lessons, or on commencing an apprentices.h.i.+p for which they are physically unfit. In some cases there is nasal obstruction from adenoids, in others the development and free play of the chest are interfered with by tight and ill-fitting garments; in all of them the muscular system is weak and the muscles of the trunk do not take their proper share in maintaining the erect posture. The most important determining factor would appear to be the habitual or repeated a.s.sumption of faulty att.i.tudes, partly from carelessness, largely from fatigue, in order to relieve the feeling of tiredness in the back. So far as is known, the condition does not occur in communities living under aboriginal conditions. In some cases there is a hereditary tendency to scoliosis; we have seen it, for example, in a father and his daughters.

The excessive use of one arm in the carrying of weights, the habit of resting on one leg more than the other, or the a.s.sumption of a faulty att.i.tude in writing or in playing the piano or violin, doubtless, determine the seat and direction of the curvature, and, when it has once commenced, tend to aggravate and to perpetuate it.

It is probable that the greater frequency of the primary curvature towards the right is a.s.sociated with the more general use of the right hand and arm, although primary curvatures towards the left are not confined to left-handed persons.

_Morbid Anatomy._--The original deviation or "primary curve" is usually in the thoracic region, and has its convexity directed towards the right side. To re-establish the equilibrium of the column, "secondary" or "compensatory" curves, with their convexities to the left, develop in the regions above and below the primary curve. It has been proved experimentally that lateral deviation of the spine is inevitably accompanied by rotation of the vertebrae around a vertical axis, in such a way that their bodies look towards the convexity of the curve, while their spines, laminae, and articular processes are directed towards the concavity (Fig. 226).

[Ill.u.s.tration: FIG. 226.--Vertebrae from case of Scoliosis, showing alteration in shape of bones.]

As the deformity increases, the individual vertebrae are distorted, the bodies becoming wedge-shaped from side to side, the base of the wedge looking towards the convexity of the curve, while the narrow end looks towards the concavity (Fig. 228). As the spine, laminae, and articular processes also undergo alterations in shape, a line uniting the tips of the spinous processes does not furnish an accurate index of the degree of lateral deviation but minimises it considerably. The muscles and ligaments are altered in length in accordance with the changes in the shape and position of the bones.

In the thoracic region, the ribs necessarily accompany the transverse processes, so that on the side of the convexity they form an undue prominence behind--the "rib-hump" (Fig. 227), while on the side of the concavity the chest is flattened and the ribs crowded together so that the intercostal s.p.a.ces are diminished or even obliterated. The converse--flattening on the side of the concavity--is seen on the front of the chest.

[Ill.u.s.tration: FIG. 227.--Adolescent Scoliosis in a girl aet. 23.]

The general shape of the thorax is altered: on the side of the convexity it is longer and narrower than normal and its capacity diminished, while on the side of the concavity it is shorter and broader and its capacity is increased.

The viscera are distorted and displaced in accordance with the altered shape of the thoracic and abdominal cavities. The twisting of the spine causes the patient to lose in stature, and the limbs appear to be disproportionately long. In advanced cases the pelvis becomes obliquely contracted--a deformity known as the _scoliotic pelvis_.