Mid-term and long-term follow-up of one-stage combined anterior-posterior approach in the treatment of pediatric active thoracic and lumbar tuberculosis

English Keywords:Active pediatric spinal tuberculosis  Vertebral body destruction  Pedicle-screw fixation  Allograft bone strut  Mid- or long-term follow up

English Abstract:

  【Abstract】 Objectives: To observe the mid-or long-term efficacy of posterior pedicle-screw fixation and fusion combined with anterior debridement and reconstruction with allograft bone strut in the treatment of pediatric active thoracic and lumbar tuberculosis. Methods: Retrospectively reviewed data of 19 pediatric patients (aged 3-10 years, mean age 6.3±2.1 years) with spinal active tuberculosis infection which resulted in at least two consecutive vertebral destruction treated in our hospital from January 2008 to January 2013. All patients underwent one-stage posterior pedicle-screw fixation and fusion combined with anterior debridement and reconstruction of spinal stability with allograft bone strut. The duration of follow-up ranged from 5 to 11 years, averaged 7.5±2.0 years, and the affected vertebral bodies ranged from 2 to 4. All patients were examined clinically and radiologically at 1 week, 3, 6 and 12 months after surgery and received X-ray examination once per 12 months to measure the Cobb angle and observe displacement, loosening, collapse of allograft bone, and any kyphotic deformity. The Cobb angle, Frankel grade, ESR and CRP before and one-week after surgery and at every reexamination of each patient were also collected and compared. All 19 patients were followed up more than 5 years, and underwent high resolution 3-D CT scan to evaluate the fusion of bone grafts. Results: During the following up, no recurrence of tuberculosis or instrumentation failure occurred. ESR and CRP at 6 months after operation were significantly different from those before surgery (P<0.05). The Frankel classification grading before surgery was: 2 cases of Grade B, 5 cases of Grade C, 9 cases of Grade D and 3 cases of Grade E; 1-week after: 1 case of Grade B, 3 cases of Grade C, 1 cases of Grade D and 14 cases of Grade E; and at final follow-up: 1 cases of Grade D (of Grade B before surgery) and 18 cases of Grade E. According to the Frankel motor score system, neurological deficits were improved at one week after surgery (an average improvement of 0.80 grades) and at final follow-up (an average improvement of 1.26 grades) than before surgery, and the differences were of statistical significance(P<0.05). The average kyphotic angle was changed significantly from a preoperative value of 41.32°±13.19° to a immediate postoperative value of 9.74°±5.80° and, with an average correction rate of 76.4%(P＜0.05). The average kyphotic angle at final follow-up was 12.32°±6.40°, with an average loss of 2.58°±0.60°. The stable kyphosis correction was 29.0°±8.9°, with an correction rate of 70.1%, and there was no significant difference in the Cobb angle between final follow-up and immediate postoperative values(P>0.05). All 19 patients gained solid fusion at both upper and lower ends of allograft bone strut, achieving Bridwell grade 1 fusion. The lower end of grafts of 2 cases out of the 19 slightly subsided, but osteophyte formed and there were trabeculae through the contact surface with no obvious loosening and dislocation of bone grafts; 1 case exhibited slight local kyphosis, with no neurological deficit and clinical symptoms. Conclusions: It is effective, practical and safe to treat vertebral destruction caused by pediatric thoracic and lumbar spinal active tuberculosis by posterior pedicle-screw fixation and fusion combined with anterior debridement and spinal stability reconstruction with allograft bone strut, and in our study, satisfactory clinical results were obtained after mid-term and long-term follow-up.