Thoracic Spine Growth Revisited

STUDY DESIGN: Cross-sectional descriptive study. OBJECTIVE: To describe the normal rate pattern of thoracic spine growth in children without any spinal deformity. SUMMARY OF BACKGROUND DATA: The knowledge of thoracic spine growth and height is important for growing spine treatment and the decision of final fusion. Currently, pediatric spinal deformity is approached as early onset and late onset with an understanding of the fast growth during the first 5 years of life. The growth data that support this classification is often cited but has not been reconfirmed with follow-up studies. METHODS: Sagittal computed tomography (CT) reformations of thoracic vertebrae were examined in children without spinal deformity. The sagittal CT cut at the widest canal diameter was identified and the measurements were performed on this image. The length of the thoracic spine was measured from the posterosuperior corner of T1 to the posteroinferior corner of the T12. RESULTS: One hundred forty-four thoracic CT scans satisfied the inclusion criteria. The analysis of the data identified two break points in the growth velocity; one at the end of the 4th year of life and the other at the beginning of the 12th year. Specifically, growth rate between 1 and 4 years was 1.71 cm/yr, between 4 and 8 years was 0.55 cm/yr, between 8 and 10 was 0.74 cm/yr, between 10 and 12 was 0.69 cm/yr, and between 12 and 16 was 1.61 cm/yr. CONCLUSION: The results show that in growing children the thoracic spine demonstrates two major growth spurts. The initial growth spurt is between the birth to the end of the fourth year of life and the second is between the 12 and 16 years of age. Between 4 and 12 years there is a steady but slower increase in thoracic height. The findings show that the fastest growth velocity may be limited to a younger age group than previously believed. This data will help guide growth friendly management strategies. LEVEL OF EVIDENCE: 2.