Posterior release and spinal wedge osteotomy for congenital thoracolumbar hemivertebra with severe rigid kyphoscoliosis deformity

English Keywords:Spinal deformity  Hemivertebra  Severe kyphoscoliosis  Posterior release  Spinal wedge osteotomy  Fusion level selection

English Abstract:

  【Abstract】 Objective：To evaluate the early clinical outcome of posterior release and spinal wedge osteotomy for congenital thoracolumbar hemivertebra with severe rigid kyphoscoliosis deformity and to discuss the selection of fusion and fixation.Method：From April 2007 to March 2010，11 patients suffering from congenital thoracolumbar hemivertebra complicated with severe rigid kyphoscoliosis were reviewed retrospectively.There were 4 males and 7 females with an average age of 17.1 years（range，14-22 years）．All hemivertebrae were single fully segmented，which were sited in T11 in 3 cases，T12 in 4 cases，L1 in 1 case and L2 in 3 cases.The mean preoperative scoliosis Cobb angle was 94.4°（range，82°-125°）.The mean scoliosis flexibility was 24.8%（range，17.4%-28.9%）.The mean preoperative kyphosis Cobb angle was 101.1°（range，72°-145°）.The mean distance from C7 plumb line to middle sacral line was 2.9cm（range，1.5-5.5cm）.All cases underwent posterior release and spinal wedge osteotomy，and the touched vertebrae（TV）（defined as the most cephalad vertebrae touched by central sacrum vertical line） were regarded as the lowest instrumented vertebrae（LIV）.1 case with tethered spinal cord and diastematomyelia underwent tethered spinal cord release plus the above-mentioned procedure.Result：All the patients underwent the operation successfully.An average of 3.0 thoracic vertebra release was performed.The average surgical time was 7.7 hours（5.5-10.0 hours），and the average blood loss was 3500ml（1000-7000ml）.There was no neurological deficit.1 patient suffered from left pleura tearing during capitulum costae resection complicated with hemopneumothoraxes who was treated by chest cavity closed drainage alone and recovered completely after 2 weeks.1 patient suffered from screw perforating back skin，that was resolved by taking out the screw 3 months later.Immediately after operation，the mean scoliosis Cobb angle was 28.0°（7°-54°），with a correction rate of 70.9%；and the mean kyphosis Cobb angle was 27.8°（20°-36°），with a correction rate of 71.7%.The average distance from C7 plumb line to middle sacral line was 0.6cm（0.1-2.3cm），with coronal imbalance correction rate of 78.1%.All patients were followed up for an average of 23.4 months（14-35 months）.At final follow-up，the mean scoliosis Cobb angle was 29.7°（8°-57°），with loss of correction rate of 7.3%.The mean kyphosis deformity had Cobb angle of 29.9°（22°-38°），with kyphosis loss of correction rate of 7.7%.The average distance from C7 plumb line to middle sacral line was 0.7cm（0.2-2.5cm）.Bony fusion was achieved in all patients，and no instrument complications as well as significant loss of correction were documented.Compared with the procedure of fusion to stable vertebrae（SV），fusion to TV saved 1.09 mobile segments.Conclusion：Posterior release and wedge osteotomy is reliable and effective for congenital thoracolumbar hemivertabra with severe rigid kyphoscoliosis.Selecting TV rather than LIV can decrease fusion segments as more as possible.