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[Efficiency of preoperative Halo-gravity traction in severe kyphoscoliosis secondary to neurofibromatosis type Ⅰ].

Objective: To evaluate the efficiency of preoperative Halo-gravity traction (HGT) in the treatment of severe kyphoscoliosis secondary to neurofibromatosis type Ⅰ (NF1). Methods: A retrospective review was conducted on patients with severe kyphoscoliosis secondary to NF1 at Department of Spinal Surgery, Drum Tower Hospital, Medical School of Nanjing University between July 2007 and May 2016. A total of 29 patients including 17 males and 12 females were finally enrolled and the age was (13.7±2.9) years. The Cobb angle of major coronal curve and global kyphosis were measured before and after HGT. The forced vital capacity (FVC)and forced expiratory volume in 1 second (FEV(1)) before and after traction were also recorded. The paired t test was used for comparison analysis. Results: The average maximum traction weight of HGT was (12.2±2.8) kg and the traction duration was (10.2±6.6) weeks. The coronal Cobb angle before HGT was (87.5±36.5)°, which improved to (68.4±25.9)° after HGT with a correction rate of (21.9±12.1)% (t=9.14, P<0.001); the average global kyphosis before HGT was (79.1±27.1)°, which improved to (59.9±19.4)° after HGT and the correction rate was (20.2±14.1)% (t=8.55, P<0.001). One patient had transient brachial plexus palsy which resolved completely after reducing the traction weight. After HGT treatment, FVC increased from (0.83±0.16) L to (0.89±0.19) L (t=1.48, P=0.12) and FEV(1) increased from (0.72±0.16) L to (0.78±0.20) L (t=0.49,P=0.63). FVC predicted and FEV(1) predicted improved from (42.9±20.1)% and (40.6±19.6)% to (46.9±20.5)% (t=0.98,P=0.33) and (43.6±25.8)% (t=1.24,P=0.22), respectively. Conclusion: Preoperative HGT in the treatment of severe kyphoscoliosis secondary to NF1 can improve spinal deformity and pulmonary function to some extent, which can further benefit the patients by improving their surgical tolerance.