Application of eggshell technique in the management of kyphotic deformity in ankylosing spondylitis

[Objective]To assess the clinical results of transpedicular lumbar wedge resection osteotomy(eggshell technique) for correction of kyphotic deformity in ankylosing spondylitis.[Methods]Thirty-four patients of ankylosing spondylitis kyphotic deformity with mean age 34.6 years old received surgical treatment.There were 27 men and 7 women.The transpedicular wedge resection osteotomy was performed through L2 or L2 and L3 vertebrae according to the preoperative Chin-brow vertical angle.[Results]All the patients stood surgery well.The operative time were 150~210 min and the blood bleeding during operation were 1 000~2 400 ml.There was no postoperative neurologic complication and no breakage of nails or failure of the internal fixation during the follow up period.The mean Chin-brow vertical angle was corrected from preoperative 41°to postoperative 5°.All patients can walk with forward vision and sagittal balance and the gait was improved significantly.[Conclusion]Posterior transpedicular lumbar wedge resection osteotomy(eggshell technique) is effective for managing kyphosis in ankylosing spondylitis.It can provide good protection for spinal cord and nerve roots.