Background The peculiar and highly variable C2 anatomy can make screw fixation more challenging and prone to potential vertebral artery or neurologic injury. Conventional C-arm fluoroscopy has several drawbacks. The a...Background The peculiar and highly variable C2 anatomy can make screw fixation more challenging and prone to potential vertebral artery or neurologic injury. Conventional C-arm fluoroscopy has several drawbacks. The aim of this research was to evaluate the accuracy of posterior C2 screw fixation using intraoperative three-dimensional fluoroscopy- based navigation （ITFN） and assess the perioperative complication rate related to screw placement. Methods A retrospective review identified patients who underwent operative management with C2 instruments using ITFN at our hospital between January 2006 and December 2012. Clinical data were obtained from medical records and final screw positions were graded according to a modified classification of Gertzbein and Robbins. Grade A and B screws were considered well positioned. Results The study included 99 patients （53 males and 46 females） who underwent posterior C2 screw fixation using ITFN. The mean Japan Orthopedic Association score improved from （6.7±1.9） points before surgery to （12.5±2.7） points at 6-month follow-up （z= ＋8.628, P 〈0.01）. The mean visual analogue scale improved from （4.1±1.2） points before surgery to （0.7±0.9） points at 6-month follow-up, with an improvement of 83.7% （z= 8.638, P 〈 0.01）. Of the 196 screws analyzed using computed tomography and chart review, 126 transarticular, 64 pedicle, and 6 pars screws were placed with 82.5% （104/126）, 89.1% （57/64）, and 100% （6/6） accuracy （grade A）, respectively; 98.5% （193/196） of screws were grade A or B （grade C, 1.5% （3/196））, and no neurologic injuries occurred. In normal C2 cases, 93 transarticulars and 47 pedicles were placed with high accuracy rates of 90.3% （84/93） and 93.6% （44/47） （grade A）, respectively. However, in cases with C2 deformity, 33 transarticular, 17 pedicle, and 6 pars screws were placed with only 60.6% （20/33）, 76.5% （13/17）, and 100% （6/6） accuracy （grade A）, respectively. Conclusion ITFN is a safe, accurate, and effective tool for posterior C2 fixation. Chin Med J 2014;127 （14）： 2654-2658展开更多
Background：Although pedicle screw placement （PSP） is a well-established technique for spine surgery,the treatment of patients with primary invasive spinal tumor （PIST） has high surgical risks secondary to destroy...Background：Although pedicle screw placement （PSP） is a well-established technique for spine surgery,the treatment of patients with primary invasive spinal tumor （PIST） has high surgical risks secondary to destroyed pedicles.Intraoperative three-dimensional fluoroscopy-based navigation （ITFN） system permits safe and accurate instrumentation of the spine with the advantage of obtaining intraoperative real-time three-dimensional images and automatic registration.The aim of this study is to evaluate the feasibility and accuracy of PSP using ITFN system for patients afflicted with PIST in the thoracic spine.Methods：Fifty-one patients diagnosed with PISTs were retrospectively analyzed,and 157 pedicles screws were implanted in 23 patients using the free-hand technique （free-hand group） and 197 pedicle screws were implanted in 28 patients using the ITFN system （ITFN group）.Modified classification of Gertzbein and Robbins was used to evaluate the accuracy of PSP,and McCormick classification was applied for assessment of neurological function.Demographic data and factors affecting accuracy of screw insertion were compared using independent t-test while comparison of accuracy of screw insertion between the two groups was analyzed with Chi-square test.Results：Of 51 patients,39 demonstrated improved neurological status and the other 12 patients reported that symptoms remained the same.In the free-hand group,145 screws （92.4%） were Grade Ⅰ,9 screws （5.7%） were Grade Ⅱ,and 3 screws （1.9%） were Grade Ⅲ.In the ITFN group,192 screws （97.4%） were Grade Ⅰ,5 screws （2.6%） were Grade Ⅱ,and no Grade Ⅲ screw was detected.Statistical analysis showed that the accuracies of pedicle screws in the two groups are significantly different （χ^2 =4.981,P =0.026）.Conclusions：The treatments of PISTs include total tumor resection and reconstruction of spine stability.The ITFN system provides a high accuracy of pedicle screw placement.展开更多
文摘Background The peculiar and highly variable C2 anatomy can make screw fixation more challenging and prone to potential vertebral artery or neurologic injury. Conventional C-arm fluoroscopy has several drawbacks. The aim of this research was to evaluate the accuracy of posterior C2 screw fixation using intraoperative three-dimensional fluoroscopy- based navigation （ITFN） and assess the perioperative complication rate related to screw placement. Methods A retrospective review identified patients who underwent operative management with C2 instruments using ITFN at our hospital between January 2006 and December 2012. Clinical data were obtained from medical records and final screw positions were graded according to a modified classification of Gertzbein and Robbins. Grade A and B screws were considered well positioned. Results The study included 99 patients （53 males and 46 females） who underwent posterior C2 screw fixation using ITFN. The mean Japan Orthopedic Association score improved from （6.7±1.9） points before surgery to （12.5±2.7） points at 6-month follow-up （z= ＋8.628, P 〈0.01）. The mean visual analogue scale improved from （4.1±1.2） points before surgery to （0.7±0.9） points at 6-month follow-up, with an improvement of 83.7% （z= 8.638, P 〈 0.01）. Of the 196 screws analyzed using computed tomography and chart review, 126 transarticular, 64 pedicle, and 6 pars screws were placed with 82.5% （104/126）, 89.1% （57/64）, and 100% （6/6） accuracy （grade A）, respectively; 98.5% （193/196） of screws were grade A or B （grade C, 1.5% （3/196））, and no neurologic injuries occurred. In normal C2 cases, 93 transarticulars and 47 pedicles were placed with high accuracy rates of 90.3% （84/93） and 93.6% （44/47） （grade A）, respectively. However, in cases with C2 deformity, 33 transarticular, 17 pedicle, and 6 pars screws were placed with only 60.6% （20/33）, 76.5% （13/17）, and 100% （6/6） accuracy （grade A）, respectively. Conclusion ITFN is a safe, accurate, and effective tool for posterior C2 fixation. Chin Med J 2014;127 （14）： 2654-2658
文摘Background：Although pedicle screw placement （PSP） is a well-established technique for spine surgery,the treatment of patients with primary invasive spinal tumor （PIST） has high surgical risks secondary to destroyed pedicles.Intraoperative three-dimensional fluoroscopy-based navigation （ITFN） system permits safe and accurate instrumentation of the spine with the advantage of obtaining intraoperative real-time three-dimensional images and automatic registration.The aim of this study is to evaluate the feasibility and accuracy of PSP using ITFN system for patients afflicted with PIST in the thoracic spine.Methods：Fifty-one patients diagnosed with PISTs were retrospectively analyzed,and 157 pedicles screws were implanted in 23 patients using the free-hand technique （free-hand group） and 197 pedicle screws were implanted in 28 patients using the ITFN system （ITFN group）.Modified classification of Gertzbein and Robbins was used to evaluate the accuracy of PSP,and McCormick classification was applied for assessment of neurological function.Demographic data and factors affecting accuracy of screw insertion were compared using independent t-test while comparison of accuracy of screw insertion between the two groups was analyzed with Chi-square test.Results：Of 51 patients,39 demonstrated improved neurological status and the other 12 patients reported that symptoms remained the same.In the free-hand group,145 screws （92.4%） were Grade Ⅰ,9 screws （5.7%） were Grade Ⅱ,and 3 screws （1.9%） were Grade Ⅲ.In the ITFN group,192 screws （97.4%） were Grade Ⅰ,5 screws （2.6%） were Grade Ⅱ,and no Grade Ⅲ screw was detected.Statistical analysis showed that the accuracies of pedicle screws in the two groups are significantly different （χ^2 =4.981,P =0.026）.Conclusions：The treatments of PISTs include total tumor resection and reconstruction of spine stability.The ITFN system provides a high accuracy of pedicle screw placement.
