Treatment Of Dystrophic Scoliosis In Neurofibromatosis Type 1 With One-stage Posterior Pedicle Screw Technique

Purpose The purpose of the study was to evaluate the clinical outcomes of the treatment of dystrophic scoliosis in NF-1 with one-stage posterior pedicle screw technique.Methods This retrospective study consisted of 22 NF-1 patients with dystrophic scoliosis treated between 2014 and 2017 in our department.The series included 13 males and 9 females with an average age of 15.8 years(range 10–32 years)and a positive family history in 9 patients(40.9%).All patients underwent one-stage posterior pedicle screw approach.The average follow-up time was 31.6 months(24-59 months).The flexibility of the main curve was evaluated by the side Bending X-ray of supine position before operation.The coronal Cobb angle,sagittal kyphosis angle,trunk global balance,and the correction of deformity after operation and at the last follow-up were evaluated by the whole-spine standing radiograph images before,after operation and at the last follow-up.The development of vertebral body and pedicle was evaluated by CT.MRI was used to evaluate paravertebral tumors and spinal cord compression and lesions in spinal canal.Results The mean coronal and sagittal Cobb's angles were 74.4°±19.2°(range39°-117°)and 45.3°±25.6°(range 11°-103°)before surgery,30.1°±12.7°(range10°-53°)and 21.1°±8.2°(range 10°-44°)after surgery,and 30.5°±12.3° and22.4°±8.6° at the last follow-up,respectively.The average flexibility of the coronal main curve was(21.7 ±11.6)%,and the postoperative coronal and sagittal curve correction were(59.1±17.4)% and(43.9±28.3)% on average,respectively.No significant correction loss was found in the last follow-up.Compared with pre-operation,coronal balance(C7PL-CSVL),apical vertebra rotation(AVR),apical vertebra translation(AVT),radiographic shoulder heightand(RSH)and sagittal balance(SVA)were significantly improved(P < 0.05).There were no significant changes in the last follow-up(P > 0.05).The mean intraoperative blood loss was1560.2±1049.7(range 600-4200)ml,and the mean duration of surgery was431.8±127.2(265-720)min.Conclusions One-stage posterior pedicle screw technique can achieve satisfactory results in the treatment of dystrophic scoliosis in NF-1.The patients of dystrophic scoliosis in NF-1 have poor flexibility of the spine.NF-1 patients have more bleeding in orthopedic operation,and the use of autotransfusion can effectively reduce the volume of blood transfusion.