Hemivertebra (HV) is a congenital spinal abnormality due to a defection of formation of one side vertebral.It is divided into 3 types according to whether it fusion with adjacent vertebral : fully segmented, semi-segmented and incarcerated.HV deformity is diagnosed depending on clinical symptoms, X rays, CT and other examine.Preoperative magnetic resonance imaging of the spine, genitourinary and cardiac ultrasound should be performed at the same time.Congenital scoliosis due to HV especially fully segmented is nonresponsive to bracing,operative treatment is the mainstay of care.The 3 basic operations are fusion in situ, convex growth arrest (epiphysiodesis), and HV resection.The single posterior approach or combined anterior and posterior approach of HV resection with instrumentation is the main method now.

Objective To explore the treatment method and clinical effect of congenital scoliosis caused by lumbosacral spine deformity in children.Methods From October 2000 to October 2015,a consecutive series of 21 congenital scoliosis due to lumbosacral spine deformity were treated in Department of Pediatric Orthopedics,the Third Affiliated Hospital of Zhengzhou University,including 12 male and 9 female,and the age was (63.1±47.3) months(3-144 months).The hemivertebrae,bone bridge,and the mixed type were found in 18 cases,2 cases,and 1 case,respectively.Hemivertebraes were on the left in 10 cases,on the right in 9 cases;involved L5 in 8 cases,S1 in 6 cases,multiple vertebrae malformation in 4 cases,wedged-shaped vertebrae involved L5 associated with contralateral bar in 1 case,unilateral unsegmented bar from L4 to S1 in 1 case,from L2 to L5 in 1 case.There were 4 cases combining with thoracic hemivertebrae,3 cases with ribs fusion and contralateral bar,16 cases(76%) with spinal cord malformations,3 cases(17%) with urinary system malformations,no congenital heart malformation.All the 21 patients were operated with one-stage posterior approach.Compared the scoliosis Cobb angle,trunk shift,operative time,blood loss volume,and complications among preoperation,post-operation and final follow-up.Results In this study,operative time was (278.9±83.1) min,blood loss volume was (355.3±249.0) mL,follow-up was (5.1±2.7) years.There were 18 cases operated with pedicle screw fixation,aged (72.9±44.1) months(16-144 months),operative time was (296.2±74.2) min,blood loss volume was(422.1±238.2) mL;the mean coronal Cobb angle of malformation area at preoperation,post operation and the final follow-up were(27.3±10.2)°,(11.0±5.9)°,(9.8±4.2)°,while the correction rate of post-operation and the final follow-up were 59.7%,64.1%.There were 3 cases operated by hemivenebra resection without pedicle screw fixation,aged 7.7 months(3-15 months),operative time was 168.3 min,blood loss volume was 103.3 mL.The mean coronal Cobb angle of malformation area at preoperation,post-operation and the final follow-up were 26.0°,13.6°,12.5°,while the correction rate of post-operation and the final follow-up were 47.7%,51.9%.The follow-up period was (5.1±2.7) years.The coronal Cobb angle of lumbosacral curve at preo-peration,post-operation and the final follow-up were (27.7±10.0)°,(11.3±5.4)°,(10.0±5.0)°,compared with preoperation,the differences of post-operation and the final follow-up were statistically significant (t=6.600,7.230,all P<0.05),with the correction rate of 59.2%,63.9%;the compensatory head side Cobb angle were(25.0±12.8)°,(11.9±8.2)°,(10.3±6.9)°,compared with preoperation,the differences of post-operation and the final follow-up were statistically significant (t=3.934,4.626,all P<0.05),with the correction rate of 52.4%,58.8%.Trunk shift was significantly improved.One case appeared fracture fixation rods breakage after 9 years,1 case appeared iliac screw breakage after 2 years but no complication such as infection,nerve injury.Conclusions The formation of obstacles and vertebral segmentation defects will lead to lumbosacral spine deformity,and scoliosis.Early one-stage posterior hemivertebra resection,breakage the bone bridge combined with pedicle screw fixation can obtain satisfactory clinical outcome.