Abstract
The segmental effect of Cotrel-Dubousset instrumentation (CDI) on the spine and thoracic cage was investigated in 38 patients with adolescent idiopathic scoliosis by preoperative and postoperative postero-anterior and lateral radiographs and computed tomography from T1 to S1. Mean Cobb angle decreased by 67%. The T5–T12 kyphosis in the hypokyphotic patients increased on average by 8.4° (P<0.001). Average preoperative as well as postoperative maximal vertebral rotation was located at the apex level, and was reduced from 19.0° to 14.3° (P<0.001). All vertebrae between the upper and lower instrumented vertebrae were significantly derotated. Average derotation for the apical zone was 4.8° (P<0.001), for the upper instrumented zone it was 2.5° (P<0.01), and for the lower instrumented zone it was 2.6° (P<0.01). Vertebral derotation was significantly higher in the apical zone than in the upper and lower instrumented zones. The apical rib hump index (RHi) decreased by 38% (P<0.001) and the cumulative RHi for the five apical levels decreased by 34% (P<0.001). The RHi for the two levels above and below the instrumentation each decreased by 20% (n.s.). No significant increase in sagittal or transverse rib cage diameter at any level was observed. The translation in the coronal plane of the apical vertebra of major right thoracic curves improved significantly (P<0.001). The preoperative flexibility index of the major curve correlated positively (r=0.47) with derotation at the apex level (P<0.01). However, no correlation was found between flexibility index and reduction of RHi at the apex level. Vertebral derotation did not correlate with reduction in RHi at any level. The study shows that CDI results in a postoperative three-dimensional improvement of the spine and a limited improvement of the thoracic cage, with no tendency towards a worsened deformity at any level within or outside the instrumentation.
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Aaro S, Dahlborn M (1981) Estimation of vertebral rotation and the spinal and rib cage deformity in scoliosis by computer tomography. Spine 6:460–467
Aaro S, Ohlund C (1984) Scoliosis and pulmonary function. Spine 9:220–222
Aaro S, Dahlborn M, Svensson L (1978) Estimation of vertebral rotation in structural scoliosis by computer tomography. Acta Radiol Diagn 19:990–992
Adams W (1865) Lectures on the pathology and treatment of lateral and other forms of curvature of the spine. Churchill, London
Armstrong GWD, Livermore NB, Suzuki N, Armstrong J (1982) Nonstandard vertebral rotation in scoliosis screening patients: its prevalence and relation to the clinical deformity. Spine 7:50–54
Bernhardt M, Bridwell K (1989) Segmental analysis of the sagittal plane alignment of the normal thoracic and lumbar spines and thoracolumbar junction. Spine 14:717–721
Bradford DS, Blatt JM, Rasp F (1983) Surgical management of severe thoracic lordosis: a new technique to restore normal kyphosis. Spine 8:420–428
Bradford DS, Lonstein JE, Moe JH, Ogilvie JW, Winter R (1987) Moe's textbook of scoliosis and other spinal deformities. Saunders, Philadelphia, pp 63–64
Bridwell K, Betz R, Capelli AM, Huss G, Harvey C (1990) Sagittal plane analysis in idiopathic scoliosis patients treated with Cotrel-Dubousset instrumentation. Spine 15:921–926
Closkey RF, Schultz A (1993) Rib cage deformities in scoliosis: spine morphology, rib cage stiffness, and tomography imaging. J Orthop Res 11:730–737
Cobb JR (1948) Outline for the study of scoliosis. Am Acad Orthop Surg Lect 5:261–275
Cotrel Y, Dubousset J, Guillaumat M (1988) New universal instrumentation in spinal surgery. Clin Orthop 227:10–23
Cundy PJ, Paterson DC, Hillier TM, Sutherland AD, Stephen JP, Foster B (1990) Cotrel-Dubousset instrumentation and vertebral rotation in adolescent idiopathic scoliosis. J Bone Joint Surg [Br] 72:670–674
Ecker ML, Betz RR, Trent PS, et al (1988) Computer tomography evaluation of Cotrel-Dubousset instrumentation in idiopathic scoliosis. Spine 13:1141–1144
Gray JM, Smith BW, Ashley RK, LaGrone MO, Mall J (1991) Derotational analysis of Cotrel-Dubousset instrumentation in idiopathic scoliosis. Spine 16:S391-S393
King HA, Moe JH, Bradford D (1983) The selection of the fusion levels in thoracic idiopathic scoliosis. J Bone Joint Surg [Am] 65:1302–1314
Krismer M, Bauer R, Sterzinger W (1992) Scoliosis correction by Cotrel-Dubousset instrumentation. Spine 17:S263-S269
Lenke LG, Bridwell KH, Baldus C, Blanke K (1992) Analysis of pulmonary function and axis rotation in adolescent and young adult idiopathic scoliosis patients treated with Cotrel-Dubousset instrumentation. J Spinal Disord 5:16–25
Ogilvie JW, Schendel M (1988) Calculated thoracic volume as related to parameters of scoliosis correction. Spine 13:39–42
Shufflebarger HL, Gepstein R, Clark R (1987) Recovery of pulmonary function after Cotrel-Dubousset instrumentation. Orthop Trans 11:498–499
Shufflebarger HL, Ellis RD, Clark C (1989) Cotrel-Dubousset instrumentation in adolescent idiopathic scoliosis. Orthop Trans 13:79–80
Wemyss-Holden SA, Burwell RG, Jacobs KJ, et al. (1993) Segmental evaluation and prediction of the effects of Cotrel-Dubousset instrumentation on the back shape and radiological deformity of adolescent idiopathic scoliosis: surgical and aetiological implications. J Bone Joint Surg [Br] 75, [Suppl II]:175
Willers U, Hedlund R (1990) Comparison of two measurements of vertebral rotation in scoliosis, Acta Orthop Scand [Suppl] 237:51
Willers U, Hedlund R, Aaro S (1993) Mid-term effects of Cotrel-Dubousset instrumentation on the configuration of the spine and the thoracic cage in thoracic idiopathic scoliosis. Eur Spine J 2:99–103
Winter RB, Lovell WW, Moe J (1975) Excessive thoracic lordosis and loss of pulmonary function in patients with idiopathic scoliosis. J Bone Joint Surg [Am] 57:972–977
Wood K, Transfeldt EE, Ogilvie JW, Schendel MJ, Bradford D (1991) Rotational changes of the vertebral-pelvic axis following Cotrel-Dubousset instrumentation. Spine 16:S404-S407
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Willers, U., Transfeldt, E.E. & Hedlund, R. The segmental effect of Cotrel-Dubousset instrumentation on vertebral rotation, rib hump and the thoracic cage in idiopathic scoliosis. Eur Spine J 5, 387–393 (1996). https://doi.org/10.1007/BF00301966
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DOI: https://doi.org/10.1007/BF00301966