[Surgical treatment of severe congenital cervical kyphosis]

Objective: To investigate the surgical treatment of severe congenital cervical kyphosis. Methods: The clinical data of patients with severe congenital cervical kyphosis (Cobb>40°) treated in Peking University Third Hospital from March 2004 to March 2018 were retrospectively summarized. In this series, 8 cases were enrolled, included 4 males and 4 females; the patients were 5-45 years old. According to the etiology, 4 patients were diagnosed with vertebral body underdevelopment, 2 with vertebral insufficiency, 1 with cervical spine congenital fusion and 1 with C(2) spinous process mecism. Five cases were treated with traction before final surgical correction. The surgical strategy was anterior correction or posterior correction or combined procedure in regards to different situation. The curvature of cervical angle was measured by two-line Cobb method, and the cervical kyphosis angle was measured on lateral radiographs in the neutral and extended position at the pre-operation and post-operation in each patient. The correction rate and evaluated Japanese Orthopedic Association (JOA) scoring for the function of spinal cord were also measured. The data before and after the operation were compared with t test. Results: In this series, the average kyphotic Cobb angle was 67°±18° and 8°±8° before and after surgical correction, respectively (t=8.471,P<0.05).The final correction rate was 87%±13%.The JOA score improved from 11.1±2.7 to 14.0±1.5 (t=-2.656, P<0.05) at the end of follow up. Conclusions: The pre-correction by cervical spine traction and final surgical correction by anterior, posterior or combined approaches of internal fixation and fusion can achieve good results and reduce risk and difficulty in operation for severe congenital cervical spine kyphosis with vertebral body underdevelopment without vertebral insufficiency and cervical spine congenital fusion. The final surgical correction by one-stage anterior, posterior or combined approaches of internal fixation and fusion can achieve good results for severe congenital cervical spine kyphosis with vertebral insufficiency and/or cervical spine congenital fusion.