The clinical features and imaging characteristics of paralytic scoliosis after spinal cord injury caused by back-bend movements in dance training

English Keywords:Spinal cord injury  Dance training  Paralytic scoliosis  Imaging characteristics

English Abstract:

  【Abstract】 Objectives: To investigate the clinical features and imaging characteristics of paralytic scoliosis secondary to spinal cord injury due to back-bend movements in dance training. Methods: The clinical and imaging data of patients with paralytic scoliosis secondary to spinal cord injury caused by back-bend movements in dance training who were admitted and treated surgically in Nanjing Drum Tower Hospital(division of spine surgery, department of orthopedic surgery) from June 2016 to August 2023 were retrospectively analyzed. All the patients underwent anteroposterior and lateral full spine X-ray examinations in sitting position. The ages of patients at the time of spinal cord injury, diagnosis of scoliosis and surgery were recorded. The planes of paraplegia, types of scoliosis, levels of involved segments, rotation of the apical vertebra, and presence of hip dislocation were analyzed. The Cobb angle of the main curve of coronal scoliosis, pelvic obliquity angle(POA), and the angle of kyphosis were measured on anteroposterior and lateral X-ray films, and the flexibility of scoliosis was calculated. The correlation between the POA and Cobb angle of the main curve was analyzed as well. Results: A total of 19 patients were included in the study. All the patients were female aged 5-9 years(6.8±1.1 years) at the time of back-bend in dance causing spinal cord injury, 6-11 years(8.6±1.3 years) at the time of diagnosis of scoliosis, and 10-26 years(13.2±3.9 years) at the time of surgery. All the patients were complete paralysis below the injury plane, which was at T10 level in 13 patients, T9 level in 2 patients, and T8 level in 4 patients. The main curve was all long C-type lumbar curvature or thoracolumbar curvature, and the number of segments involved in the main curve was 7-13(9±2), the Cobb angle was 50°-110°(74.2°±14.6°), and the flexibility of the main curve was 30%-54%(41%±10%). The apex rotation classified by Nash-Moe method fell in Ⅳ degree rotation in 12 cases, Ⅲ degree in 6 cases, and Ⅱ degree in 1 case. In sagittal plane, lumbar kyphosis was observed in 15 cases(78.9%); The local kyphosis angle was 27°-47°(34.3°±5.8°), and the lumbar lordosis angle was -47°-55°(-16.9°±34.1°); The thoracic vertebrae showed a compensated kyphosis reduction or even lordosis, with a thoracic kyphosis angle of -10°-25°(10.4°±9.1°). All the patients were complicated with hip subluxation, 17(89.5%) patients among which were unilateral, and most were located on the concave side of the main curve; 2(10.5%) patients were complicated with bilateral subluxation, which was more serious on the concave side of the main curve. All the patients had pelvic tilt, with a POA of 9°-39°(22.8°±8.4°). Pearson correlation analysis showed that there was a significant correlation between the POA and Cobb angle of main curve(r=0.635, P<0.05). Conclusions: Patients with paralytic scoliosis secondary to spinal cord injury due to back-bend movements in dance training present with a long C-type lumbar curve or single thoracolumbar curve, which has a large curve span, long segments involvement, severe vertebral rotation, relatively soft deformity, and short compensatory curve at the proximal end of the main curve. All the patients are combined with pelvic tilt and hip subluxation on the concave side of the main curve. Pelvic tilt is positively correlated with the severity of scoliosis. In the sagittal plane, a compensatory decrease in the thoracic kyphosis is manifested, and lumbar or thoracolumbar kyphosis is presented.