Campbell Robert M, Smith Melvin D, Hell-Vocke Anna K
Department of Orthopedics, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78284, USA.
J Bone Joint Surg Am. 2004 Mar;86-A Suppl 1:51-64.
Children with congenital thoracic scoliosis associated with fused ribs with a unilateral unsegmented bar adjacent to convex hemivertebrae will invariably have curve progression without treatment. Surgery has been thought to have a negligible growth-inhibition effect on the thoracic spine in such patients because it has been assumed that the concave side of the curve and the unilateral unsegmented bar do not grow, but we are unaware of any conclusive studies regarding this assumption.
The changes in the length of the concave and convex sides, anterior and posterior vertebral edges, posterior arch, and unilateral unsegmented bars of the thoracic spine were measured in the twenty-one children with congenital scoliosis and fused ribs after expansion thoracoplasty had been carried out with use of a vertical, expandable titanium prosthetic rib. Three of these children had undergone posterior spinal fusion previously. Measurements were made with use of a three-dimensional software program that analyzed baseline and follow-up computed tomography scans. The technique was validated through measurement of the thorax of a small female adult cadaver.
The patients without spine fusion had an average age of 3.3 years at the time of the baseline computed tomography scan, and the average duration of follow-up was 4.2 years. On the average, these patients showed significant growth (p < 0.0001) of the concave side of the thoracic spine (an increase in length of 7.9 mm/yr, or 7.1%/yr) and the convex side (8.3 mm/yr, or 6.4%/yr) compared with the baseline lengths. There was no significant difference in the increases in length (p = 0.38) between the concave and convex sides. Eleven patients with an unsegmented bar had an average 7.3% increase in the length of the bar (p < 0.0001). In the three children with prior spinal fusion, the increase in length averaged only 4.6 mm/yr (3%/yr) on the concave side of the thoracic spine and 3.7 mm/yr (2.2%/yr) on the convex side; both increases were significant (p < 0.0001).
Longitudinal growth of the thoracic spine in a normal child has been estimated to be 0.6 cm/yr between the ages of five and nine years. After expansion thoracoplasty, growth of the thoracic spine was approximately 8 mm/yr in our series of children with congenital scoliosis and fused ribs. After expansion thoracoplasty, both the concave and the convex side of the thoracic spine and unilateral unsegmented bars appeared to grow in these patients. When a thorax is already foreshortened by congenital scoliosis, control of spine deformity with expansion thoracoplasty allows growth of the thoracic spine, and it is likely that the longer thorax provides additional volume for growth of the underlying lungs with probable clinical benefit.
患有先天性胸段脊柱侧凸并伴有肋骨融合且在凸侧半椎体相邻处有单侧未分节骨桥的儿童，若不治疗，侧弯必然会进展。手术一直被认为对此类患者的胸椎生长抑制作用可忽略不计，因为据推测侧弯凹侧和单侧未分节骨桥不会生长，但我们尚未知晓关于这一推测的任何确凿研究。
在21例患有先天性脊柱侧凸和肋骨融合的儿童中，使用垂直可扩张钛制人工肋骨进行胸廓成形术后，测量胸椎凹侧和凸侧、椎体前后缘、后弓以及单侧未分节骨桥的长度变化。其中3例儿童此前已接受后路脊柱融合术。测量使用三维软件程序，该程序分析基线和随访时的计算机断层扫描图像。该技术通过测量一名成年女性小尸体的胸廓进行了验证。
未行脊柱融合术的患者在基线计算机断层扫描时的平均年龄为3.3岁，平均随访时间为4.2年。平均而言，与基线长度相比，这些患者胸椎凹侧（长度每年增加7.9 mm，即每年增加7.1%）和凸侧（每年增加8.3 mm，即每年增加6.4%）均有显著生长（p < 0.0001）。凹侧和凸侧长度增加量无显著差异（p = 0.38）。11例有未分节骨桥的患者，骨桥长度平均增加7.3%（p < 0.0001）。在3例先前接受过脊柱融合术的儿童中，胸椎凹侧长度平均每年增加仅4.6 mm（每年增加3%），凸侧为每年增加3.7 mm（每年增加2.2%）；两者增加均有显著意义（p < 0.0001）。
正常儿童胸椎的纵向生长在五至九岁之间估计为每年0.6 cm。在我们这组患有先天性脊柱侧凸和肋骨融合的儿童系列中，胸廓成形术后胸椎生长约为每年8 mm。胸廓成形术后，这些患者的胸椎凹侧和凸侧以及单侧未分节骨桥似乎都在生长。当胸廓因先天性脊柱侧凸已经缩短时，通过胸廓成形术控制脊柱畸形可使胸椎生长，而且较长的胸廓可能为其下方肺部的生长提供额外空间，可能具有临床益处。
