Posterior Release And Spinal Wedge Osteotomy For Congenital Thoracolumbar Hemivertebra With Severe Rigid Kyphoscoliosis

Objective: To evaluate the early clinical efficacy and safety of posterior release andspinal wedge osteotomy for congenital thoracolumbar hemivertebra of severe rigidkyphoscoliosis and to discuss the selection of fusion and fixation.Methods: From April2007to March2010, eleven patients due to congenitalthoracolumbar hemivertebrae of severe rigid kyphoscoliosis,4males and7femaleswith an average age of17.1years（range,14-22years）．All hemivertebra are singlefully segmented, T11in3cases, T12in4cases, L1in1cases, L2in3cases. Themean preoperative scoliotic Cobb angle was94.4°（range,82°-125°）. The meanscoliotic flexibility was24.8%（range，17.4%-28.9%）. The mean preoperativekyphotic Cobb angle was101.1°(range,72°-145°).The mean distance from C7plumb line to middle sacral line was2.9cm (range，1.5-5.5cm). All cases were treatedby posterior release and spinal wedge osteotomy, and select touched vertebrae (TV,which was defined as the most cephalad vertebrae touched by central sacrum verticalline) as the lowest instrumented vertebrae (LIV).1case with tethered spinal cord anddiastematomyelia underwent bony spine resection and tethered spinal cord releasingintraoperative.Results：All the patients underwent the operation successfully. An average of3.0thoracic vertebra were released. The average surgical time was7.7hours (5.5-10.0hours) and the average volume of blood loss was3500ml (1000-7000ml).There was nocomplaint of major complication such as neurological deficit.1patient suffered leftpleura tearing during capitulum costae resection and had hemopneumothoraxes，whichwas resolved by chest cavity closed drainage alone and recovered completely after2weeks.1patient suffered nail break through skin and a nail tail exposed, which wastreated by taking out the nail3months postoperatively and recovered completely. Atimmediate assessment after operation，the mean scoliotic Cobb angle was28.0°(7°-54°), with scoliosis correction of70.9%. The mean kyphotic Cobb angle was27.8°(20°-36°),with correction rate of71.7%.The distance from C7plumb line to middlesacral line was0.6cm（0.1-2.3cm）,with coronal balance correction rate of78.1%.Allpatients were followed up for an average of23.4months（14-35months）.At finalfollow-up，the mean scoliotic Cobb angle was29.7°(8°-57°)，with correction lossof7.3%. The mean kyphotic deformity had Cobb angle of29.9°(22°-38°）,withkyphotic correction loss of7.7%. The distance from C7plumb line to middle sacralline was0.7cm (0.2-2.5cm).Bony fusion was achieved in all patients， and noinstrument complications as well as no significant correction loss was documented.Compared to fusion to the stable vertebrae (SV), fusion to the touched vertebrae(TV)save1.09mobile segments.Conclusion: Posterior release and wedge osteotomy is a reliable and safe method forcongenital thoracolumbar hemivertabra with severe rigid kyphoscoliosis; Select TV asthe lowest instrumented vertebrae can achieve a good capability of correction andreduce fusion segments than SV.