SPINE, CURVATURE OF TILE. There arc two perfectly distinct forms of curvature, viz., LATERAL CURVATURE—arising from weakness of the bones, ligaments, and mus. cles, and fearfully common in girls of the middle and upper classes, between the ages of 10 and 10—and ANGULAR CURVATURE (frequently known as POTT'S CURVATURE, or the MALADY OF POTT, in consequence of that eminent surgeon having been the first to describe its true nature), which consists of caries of the bodies of the vertebne, and is by far the more serious affection of the two.
"Lateral Curvature, or Distortion, denotes deformity of the bones of the spine and chest; with corresponding change of the structure in relation to them. It is called 'lateral,' from the spine being curved sideways; and to distinguish it from 'angular' i deformity, in which the spine is directed from behind forward, owing to excavations in its forepart' from caries." The above definition is taken from Mr. Shaw's article on this affection in Holmes's System of Surgery, vol. iv. p. 844, an article from which we have borrowed freely in relation to the symptoms and causes of the disease. The first thing that commonly attracts attention is a projection of one scapula, or an elevation of one shoulder, generally the right ; the right shoulder and right side of the chest being un naturally high and rounded, while on the left side, the shoulder is depressed, and the side of the chest concave. On examination, the spine is found to have acquired a spiral appearance, "not unlike what might have been produced if it had been taken, when soft, at both ends by the two hands, and twisted as a washerwoman wrings a wet cloth." —Shaw, op. cit. In advanced stages of the distortion, the dorsal curve increases abruptly to such an extent as to render it angular, the attending contortion being similarly abrupt. This condition gives rise to various changes, including a humped appearance, a great displacement of the ribs, a diminution of the cavity of the chest, and a proportionate wasting of the lung. In consequence of these physical changes, the patient can no longer walk in a simple and natural manner, but exhibits a halting, jerking, awkward gait.
The following may be noticed amongst the principal causes of lateral curvature: 1. The suppleness of the spine in the young, its structures being then more gristle than the bone, and the column virtually immature. 2. Weakness of the muscles, which are seldom
properly exercised in girls of the age and class in which this disorder occurs. This muscular debility is usually followed by deterioration of the bones and their ligaments, and this, apart from other obvious and direct bad effects, tends to make all the compon ent parts of the spine—vertebrm and articulations—more prone to yield to the superin ctunbent weight, and to become distorted. These evil results are increased by prolonged stooping. Ashen we enter a school, shortly before the breaking up of the class, we usually find most of the pupils standing or sitting in a tired lounging position. They are instinctively relieving the pain of over-fatigue by throwing the weight on the insen sible fibrous structures, and thus relieving the aching muscles. When such attitudes are long indulged in, the ligaments undergo a process of over-stretching, and a general looseness of the vertebral joints is the result. By standing on one leg, or, more correctly speaking, by throwing all the weight of the body on one foot, the body is kept upright with the least possible expenditure of muscular power. Hence, a weak and fragile girl is induced to adopt this position. Too long indulgence in this habit will, to a certainty (for anatomical reasons, into which we have not space to enter), aggravate existing cur vature, and induce it, if it did not pre-exist.
However slight a curve in the spine of a young girl may be, it ought to be deemed of importance; for when the column inclines laterally even to a slight degree, the super incumberent weight ceases to be supported on the line of the vertical axis, and falls on the oblique processes of the side to which she leans; and these processes becoming rapidly diminished in length by absorption, induced by this abnormal pressure, general distortion rapidly commences. With regard to the final issue of a case, distortion be ginning at the age of 10 is more dangerous than at 14, because the disease runs a more rapid course in the younger cases. A cure is, for the same reason, more easily affected in the younger patient. If the patient's age be beyond 16, little can be done beyond checking the further progress of the deformity.