Risk Factors for Progression of Cervical Congenital Scoliosis and Associated Compensatory Curve Behavior

Abstract

Background: This study investigated risk factors for progression of deformity in pediatric congenital cervical scoliosis (CCS) and evaluated the correlation between congenital cervical curves and compensatory thoracic and lumbar curves. Methods: Medical records were retrospectively reviewed for 38 pediatric patients with CCS with a minimum 2-year follow-up. Curve progression was defined as >10° increase in cervical coronal curve angle between presentation and last follow-up. Results: A total of 38 patients (16 girls, 22 boys) with a mean age at presentation of 5.6 ± 4.1 years met the inclusion criteria. Sixteen patients (42%) had curve progression with a mean follow-up of 3.1 ± 3.0 years. At presentation, T1 slope was significantly larger among children with progressive deformities (p = 0.041). A total of 18 of the 38 patients with strictly cervical spine deformity were then selected for subanalysis to evaluate the progression of compensatory curves. Cervical major coronal curves were found to significantly correlate with lumbar major coronal curves (r = 0.409), C2 central sacral vertical line (CSVL) (r = 0.407), and C7-CSVL (r = 0.403) (p < 0.05). Thoracic major coronal curves did not significantly correlate with cervical major coronal curves (r = 0.218) (p > 0.05). Conclusion: In conclusion, 42% of osseous CCS curves progressed over time in the overall cohort, and high initial T1 slope was found to be most highly correlated with progression of cervical deformity. Cervical major coronal curves significantly correlated with lumbar curve magnitude but not with thoracic curve size in isolated CCS, possibly due to the increased flexibility of the lumbar spine which may allow greater compensatory balance and thus have a greater correlation with cervical curve magnitude and possibly progression.

Keywords: cervical spine deformity; compensatory curve; congenital cervical scoliosis; pediatric scoliosis; risk factors; secondary curve.

Figure 1

(A–C). A 10-year-old boy diagnosed with congenital cervical scoliosis (CCS) initially (A). This patient has C3 and C7 hemivertebrae with progression of cervical and compensatory curves (B,C).

Figure 1

(A–C). A 10-year-old boy diagnosed with congenital cervical scoliosis (CCS) initially (A). This patient has C3 and C7 hemivertebrae with progression of cervical and compensatory curves (B,C).

Figure 1

(A–C). A 10-year-old boy diagnosed with congenital cervical scoliosis (CCS) initially (A). This patient has C3 and C7 hemivertebrae with progression of cervical and compensatory curves (B,C).

Figure 2

(A–C). An 8-year-old boy diagnosed with CCS with progression of cervical deformity and compensatory curve. (A) PA radiograph shows a C7 hemivertebra. (B) Lateral radiograph. (C) Coronal CT highlights the left C7 hemivertebra. Patients with thoracic or lumbar vertebral anomalies (such as hemivertebrae, butterfly vertebrae, etc.) were excluded from this study. This was to best ensure that any compensation in the thoracic or lumbar regions was not due to vertebral anomalies in those regions.

Figure 2

(A–C). An 8-year-old boy diagnosed with CCS with progression of cervical deformity and compensatory curve. (A) PA radiograph shows a C7 hemivertebra. (B) Lateral radiograph. (C) Coronal CT highlights the left C7 hemivertebra. Patients with thoracic or lumbar vertebral anomalies (such as hemivertebrae, butterfly vertebrae, etc.) were excluded from this study. This was to best ensure that any compensation in the thoracic or lumbar regions was not due to vertebral anomalies in those regions.

Figure 2

(A–C). An 8-year-old boy diagnosed with CCS with progression of cervical deformity and compensatory curve. (A) PA radiograph shows a C7 hemivertebra. (B) Lateral radiograph. (C) Coronal CT highlights the left C7 hemivertebra. Patients with thoracic or lumbar vertebral anomalies (such as hemivertebrae, butterfly vertebrae, etc.) were excluded from this study. This was to best ensure that any compensation in the thoracic or lumbar regions was not due to vertebral anomalies in those regions.

Figure 3

(A) Distribution of patients stratified by vertebral level of osseous anomaly. Hyphenated columns represent junctional deformities. (B) Pie chart depicting proportions of types of osseous anomalies, characterized as failures of formation, failures of segmentation, or failures of both.

Figure 4

Distribution of patients stratified by vertebral level of apex of deformity.

Figure 5

(A,B) Initial PA and lateral radiograph of a 7-year-old child with a 19° cervicothoracic scoliosis and T1 slope of 31°. (C,D) Follow-up PA and lateral radiographs showing progression of the curve to 38° over 8 years.

Figure 6

(A,B) Initial PA and lateral radiograph of a 2-year-old child presenting with 17° of scoliosis at the cervicothoracic junction and T1 slope of 11°. (C,D) Follow-up radiographs showing a stable curve approximating 18° 4 years later.

Figure 7

Scatterplot of thoracic or lumbar major coronal curves (y-axis) compared to cervical major coronal curves (x-axis). Thoracic vs. cervical major coronal curves are depicted by the triangles. Lumbar vs. cervical major coronal curve are depicted by the squares. The corresponding Pearson correlation and significance are listed to the right. The asterisk denote no value since the x and y values are the same.