The effectiveness and safety of revision surgery with vertebral column decancellation for spinal deformity

English Keywords:Spinal deformity  Revision surgery  Sagittal balance  Osteotomy

English Abstract:

  【Abstract】 Objectives: To evaluate the effectiveness and safety of revision surgery for the severe spinal deformity by utilizing the technique of vertebral column decancellation(VCD). Methods: A retrospective analysis was carried out for 20 cases suffered from spinal deformity and undergoing revision surgery in 301 Hospital from January 2010 to January 2012. Age ranged from 17 to 58 years old and the average age was 34.5±11.6 years. There were 12 males and 8 females. Twenty patients included 6 cases with kyphosis secondary to ankylosing spondylitis, 4 cases with congenital kyphosis, 4 cases with kyphoscoliosis secondary to spinal tuberculosis, 3 cases with congenital kyphoscoliosis and 3 patients with adolescent idiopathic scoliosis, all patients were diagnosed by the radiographic and medical records. The average interval from revision surgery to previous corrective surgery was 5.6±3.3 years. The mean Cobb angle of coronal plane was 64.2°±15.6° and 92.7°±9.7° in sagittal plane. All cases received revision surgery of VCD under general anesthesia. Operation time, intraoperative bleeding and the complications of perioperation were recorded. All 20 study subjects underwent whole spinopelvic right and lateral radiography at the time of pre-revision surgery, one week after revision and the final follow-up. Sagittal parameters included Cobb angle, thoracolumbar kyphosis angle(TK), lumbar lordosisc(LL), sacral slope(SS), pelvic tilt(PT), pelvic incidence(PI) and sagittal vertical axis(SVA). Coronal parameters included Cobb angle, apical vertebral offset distance and the relative height of shoulders. Scoliosis Research Society-22(SRS-22) was used to evaluate the life quality of 20 patients at different time points pre-revision surgery and 6 months of post-operation. Results: All surgeries were performed successfully, osteotomies were performed at 1.5±0.6 levels(average, 1-2). Time of revision surgery ranged from 4 to 6.5 hours(average, 5.3±0.7h) and the blood loss ranged from 600 to 1300ml(average 830.0±150.5ml). All incisions healed by first intention. No complication occurred such as infection, deep venous thrombosis of lower extremities, respiratory failure or nerve injury occurred during follow-up. Three cases suffered from leakage of cerebrospinal fluid and two cases were complicated with arteria mesenterica superior syndrome. The average hospital stay of all cases was 13.9±2.4 days. The follow-up ranged from 18 months to 40 months(average, 27.6±2.8 months). The Cobb angle was corrected to 15.7°±4.9° in coronal plane and 28.7°±8.7° in sagittal plane. Cobb angle of coronal plane, apical vertebral offset distance and the relative height of shoulders at one week after operation obviously improved than pre-revision surgery(P<0.05). And there was no statistical significance compared to final follow-up. The sagittal parameters except PI including Cobb angle, TK, LL, SS, PT, SVA at one week after revision operation had statistical significance compared to pre-revision surgery(P<0.05). The correction rate of coronal Cobb angle was (75.5±4.5)% and sagittal Cobb angle was (63.5±5.7)%. The loss of correction at final follow-up compared to one week after revision surgery was 26.5% in coronal plane and 34.1% in sagittal plane. The parameters of SRS-22 such as function, pain, appearance, mental and satisfaction of 6 months after revision surgery improved obviously compared to pre-revision surgery(P<0.05). Conclusions: The posterior VCD can restore the balance and stabilization of coronal and sagittal of spine, also can avoid the complications such as the excessive shorten and nerve injury of spinal cord in the procedure of revision severe spinal deformity surgery. This technique is an safe and effective remedial measure for spinal deformity after previous surgery.