A physiological approach to surgical treatment of progressive early idiopathic scoliosis

Abstract

IntroductionThe results of previous studies have shown that in girls with right convex thoracic adolescent idiopathic scoliosis (IS) there is significantly increased vascularity of the left breast as compared with the right one [10]. It has also been found that in deceased women with right convex thoracic IS, the mean length of the ribs corresponding to the apical and the two periapical vertebrae was greater on the concave than on the convex side [11]. These changes were ascribed to disturbed sympathetic function. Indeed, in growing rabbits stimulation of the longitudinal rib growth by unilateral resection of intercostal nerves, including the sympathetic fibres, resulted in hyperaemia of the denervated anterior hemithorax [1], increased longitudinal rib growth [2] and scoliosis with the convexity to the opposite side of the denervation and characteristics of IS in humans [3].The inter-related results of these and other clinical and experimental studies have provided evidence supporting the thoracospinal theory of the pathogenesis of IS. According to this new theory, stimulation of longitudinal growth of the left ribs is the origin of right convex IS in adolescent girls [15].In connection with these studies, experiments were also undertaken to investigate the possibility of correcting or suppressing the progression of scoliosis induced in rabbits.In a first experiment, scoliosis was induced by unilateral resection of three intercostal nerves on the left side in growing rabbits. Three months after the operation, all rabbits had developed scoliosis with a mean Cobb angle of 22.5°. The concavity of the curve was on the side of the denervation. At this time, one rib of the convexity, one, two, three or four spaces above the apical vertebra of the curve, after osteotomy, was mechanically elongated by 7 mm using a metallic expander. The initial scoliosis was corrected immediately after the operation, and remained unchanged 3 weeks later [14] (Fig. 1).In a second experiment, three intercostal nerves were resected on one side of the thorax in rabbits with a mean body weight of 350 g. Then the animals were allocated into three groups, with six rabbits in each. In the first group, used as reference, a progressive scoliosis developed in all animals, which 3 months after the operation averaged 27.0°. In the second group, group A, 1 month af- AbstractThe results of previous clinical and experimental studies have provided accumulated evidence for the role of rib asymmetry in the pathogenesis of idiopathic scoliosis (IS). Moreover, it has been shown that scoliosis induced in rabbits can be corrected by elongation or growth stimulation of ribs on the side of the convexity. Taking these observations into consideration, a 7-year-old girl with right convex thoracolumbar IS was operated upon by 2-cm shortening of three concave ribs. The preoperative coronal Cobb angle was 46°and the sagittal angle was 55°. Twenty-seven months after the operation the curves were reduced to 21°a nd 35°, or by 54 and 36%, respectively. It is concluded ...

Biomechanical modelling of growth modulation following rib shortening or lengthening in adolescent idiopathic scoliosis

“…The modification of the spine curves is in agreement with the case of the 7 year old scoliotic patient reported by XIONG and SEVASTIK (1998). The concave rib shortening of three ribs (7th, 8th and 9th) resulted in a decrease in the Cobb angles, both in the frontal and lateral planes, respectively, from 46 ° to 21 °, and from 55 ° to 35 °, after 27 months.…”

“…Animal studies have shown that rib resection, either shortening or lengthening, can induce (PIGGOTT, 1971;SEVASTIKOGLOU et al, 1978;SEVASTIK et al, 1993;DEGUCHI et al, 1995) and correct (SEVASTIK et al, 1990;DEGUCHI et al, 1996DEGUCHI et al, , 1997 scoliosis. XIONG and SEVASTIK (1998) reported the case of a young scoliotic patient who was treated by shortening of three ribs on the curve concavity and who has shown continuous improvement of the spinal curvature. A previous b iomechanical study using a finite element model of the trunk demonstrated that, although rib surgery produces only slight immediate geometrical changes, concave side rib shortening and convex side rib lengthening can induce load patterns on the end-plates that might act against scoliosis progression (GREALOU et al, 2002;CARRIER et al, 2004).…”

Multilevel Spinal Growth Modulation With an Anterolateral Flexible Tether in an Immature Bovine Model

“…19 There is a single case of a 7-year-old girl that had shortening of three ribs on the concavity of a scoliotic curve and 27 months postoperatively has a 54% reduction in the magnitude of her curve. 20 The use of growth tethering in clinical practice has yielded inconsistent results. In 1954, Smith et al described the stapling of vertebral bodies in three patients with congenital scoliosis.…”

27 Correction Without Fusion

“…Xiong and Sevastik reported a successful case of treatment by the shortening of three concave-side ribs in a 7-year-old girl with a right thoracolumbar scoliosis treated by a shortening of three concave ribs. 11 The patient's curve decreased from 46 degrees to 21 degrees over a period of 27 months. It is surprising that the finite element model predicted a more modest curve correction, while another case report described a 50% reduction in curvature within the same time frame.…”