A Meta -Analysis Of Surgical Treatment In Lenke 5C Adolescent Idiopathic Scoliosis

Backgrounds:Selective fusion is recommended for Lenke 5C curvature of adolescent idiopathic scoliosis.Only thoracolumbar/lumbar fusion is performed,and unfused thoracic curvature will be spontaneously corrected to maintain coronal balance.However,Newton et al.reported that 27% of Lenke 5C AIS patients had their thoracic curve included in the fusion,the specific reason is not clear.Recent studies have shown that spontaneous correction of the thoracic curvature after fusion of the thoracolumbar/lumbar curvature alone produces good coronal balance.In adolescent idiopathic scoliosis(Lenke 5C AIS)patients with primarily or structurally thoracolumbar/lumbar curve,and non-structurally thoracic curve,the determination of fusion range is still very controversial.Anterior approach due to shorter fusion segment was the main surgical method for Lenke 5C patients.However,the lack of derotatory ability,the potential impact of pulmonary function,and the high rate of internal fixation failure have led to a decline in the use of anterior approaches.Although posterior surgery can achieve the same or better three-dimensional orthopedic results as anterior surgery,posterior surgery problems such as pedicle screw misplacement,longer operation time and higher cost should also be considered.The optimal surgical approach for the Lenke 5C curve is controversial.Objectives:To compare radiographic parameters of patients with Lenke 5C cuvers undergoing STF or NSTF and Anterior approach or Posterior approach,and to provide the evidence-based medical evidence for the treatment of Lenke 5C AIS patients.Methods:A PubMed 、 Web of Science 、 EMbase 、 Cochrane search was conducted using combinations of the key words “ Lenke 5 ” or“thoracolumbar/lumbar curve”.Review manager 5.3 software was usd to conduct Meta analysis on the literatures that met the inclusion criteria.Results:There are 11 articles in the literatures were selected,including 749 Lenke 5C cases.Meta analysis showed radiographic findings were significantly worse in Non-STL/LF,as measured by the thoracolumbar/lumbar Cobb angle(MD:-2.97[-5.55,-0.38],P=0.02)、thoracic Cobb angle(MD:-9.76[-14.27,-5.25],P<0.001)and AVT(MD:-1.00[-1.64,-0.36],P=0.002).No significant differences were showed in the thoracic kyphosis、coronal balance、age、Risser sign and EBL between STL/LF and Non-TL/LF.The STL/LF represented significant shorter fusion segments and less operation time compared to Non-STL/LF.Meta analysis showed no significantly differences in the change values and correction rate of TL/L Cobb angle between anterior approach and posterior apprach.Compared to posterior approach,The anterior approach represented a shorter fusion segements compared to posterior approach(MD:-1.28(-1.67,-0.88),P<0.00001).The posterior approach obtained a larger increasing Cobb angle of lumbar Lordosis(MD:-5.39[-7.15,-3.63],P<0.00001)and thoracic kyphosis(MD:-3.30[-4.81,-1.78],P<0.0001)than the anterior approach.Conclusions:This is a Meta analysis comprehensive comparing operative treatment in Lenke 5C,including STL/LF 、 Non-STL/LF and anterior approach、posterior approach.Thoracic kyphosis、coronal balance、age、Risser sign and EBL were equivalent between STL/LF and Non-STL/LF.Radiographic findings were significantly worse in Non-STL/LF,as measured by the thoracolumbar/lumbar Cobb angle、thoracic Cobb angle and AVT.The STL/LF represented significant shorter fusion segments and less operation time compared to Non-STL/LF.No significantly differences in the change values and correction rate of TL/L Cobb angle between anterior approach and posterior apprach.Compared to posterior approach,The anterior approach represented a shorter fusion segements.The posterior approach obtained a larger increasing Cobb angle of lumbar Lordosis and thoracic kyphosis than the anterior approach.