Objectives:To explore and evaluate the efficacy of preoperative MRI in predicting decompression outcomes in expansive open-door laminoplasty for cervical spondylosis.Methods:The clinical data of 48 patients with cervical spondylotic myelopathy(CSM)who underwent cervical expansive open-door laminoplasty in our hospital from January 2020 to October 2022 were retrospectively analyzed.There were 35 males and 13 females,aged from 41 to 78 years old(59.9±9.1 years).The midsagittal diameter of the dural sac of the compressed segment was measured on the midsagittal view of MRI T2WI before operation.The line between the anterior inferior edge of the superior lamina and the anterior superior edge of the inferior lamina was set as the lamina line(LL).The measurement of the midsagittal diameter from the anterior dural margin to the LL was the LL simulated decompression midsagittal diameter.The spinal cord's actual decompression midsagittal diameter was measured as the dural sac midsagittal diameter at the decompressed level on the MRI T2WI mid-sagittal plane one month postoperatively.The correlation between the actual postoperative midsagittal diameter of spinal cord decompression at 1 month and the simulated decompression midsagittal diameter using LL was analyzed.The prediction was defined as accurate when there was no statistically significant difference(P＞0.05)between the preoperative simulated decompression midsagittal diameter using LL and the actual postoperative decompression midsagittal diameter according to paired t test analysis.For cases predicted accurately,the effect of C2-C7 Cobb angle on the predictive value of the LL simulated decompression was assessed.The postoperative efficacy was evaluated using the modified Japanese Orthopaedic Association(mJOA)score at 12-month follow-up.Results:The spinal cord's actual decompression midsagittal diameter after the operation was 14.1±1.4mm and the midsagittal diameter in the preoperative LL simulated decompression was 14.3±1.6mm,which were both significantly increased compared with the preoperative midsagittal diameter of the dural sac at the compressed level of 10.1±1.5mm(P＜0.05).Correlation analysis showed that the predictive accuracy rate of the midsagittal diameter in LL simulated decompression was 93.8％(45/48).The preoperative C2-C7 Cobb angle of the 45 patients with accurate prediction were 24.2°±6.7°,and the postoperative C2-C7 Cobb angle was 24.2°±6.3°,and there was no statistically significant difference(P＞0.05).The 45 patients with accurate predictions were grouped with preoperative C2-C7 Cobb angles into 16 patients with Cobb＜20° and 29 patients with Cobb ≥ 20°.The mean midsagittal diameter of LL simulated and actual decompression in pa-tients with Cobb ≥ 20° was significantly greater than that in patients with Cobb＜20°(P＜0.05).In the three pa-tients with inaccurate prediction,the C2-C7 Cobb angle was significantly reduced postoperatively compared to preoperatively,and the actual midsagittal diameter of the dural sac after the operation was smaller than that in the LL simulated decompression(P＜0.05).All the 48 patients were followed up for 12 to 36 months(22.5±7.0 months),and the mJOA score at 12-month postoperative follow-up was 16.5±0.8 points,which was sig-nificantly higher than that before operation(P＜0.05).Conclusions:The application of MRI T2WI midsagittal LL simulated decompression before operation can well predict the effect of spinal cord decompression in cer-vical expansive open-door laminoplasty.

Objectives:To explore and evaluate the efficacy of preoperative MRI in predicting decompression outcomes in expansive open-door laminoplasty for cervical spondylosis.Methods:The clinical data of 48 patients with cervical spondylotic myelopathy(CSM)who underwent cervical expansive open-door laminoplasty in our hospital from January 2020 to October 2022 were retrospectively analyzed.There were 35 males and 13 females,aged from 41 to 78 years old(59.9±9.1 years).The midsagittal diameter of the dural sac of the compressed segment was measured on the midsagittal view of MRI T2WI before operation.The line between the anterior inferior edge of the superior lamina and the anterior superior edge of the inferior lamina was set as the lamina line(LL).The measurement of the midsagittal diameter from the anterior dural margin to the LL was the LL simulated decompression midsagittal diameter.The spinal cord's actual decompression midsagittal diameter was measured as the dural sac midsagittal diameter at the decompressed level on the MRI T2WI mid-sagittal plane one month postoperatively.The correlation between the actual postoperative midsagittal diameter of spinal cord decompression at 1 month and the simulated decompression midsagittal diameter using LL was analyzed.The prediction was defined as accurate when there was no statistically significant difference(P＞0.05)between the preoperative simulated decompression midsagittal diameter using LL and the actual postoperative decompression midsagittal diameter according to paired t test analysis.For cases predicted accurately,the effect of C2-C7 Cobb angle on the predictive value of the LL simulated decompression was assessed.The postoperative efficacy was evaluated using the modified Japanese Orthopaedic Association(mJOA)score at 12-month follow-up.Results:The spinal cord's actual decompression midsagittal diameter after the operation was 14.1±1.4mm and the midsagittal diameter in the preoperative LL simulated decompression was 14.3±1.6mm,which were both significantly increased compared with the preoperative midsagittal diameter of the dural sac at the compressed level of 10.1±1.5mm(P＜0.05).Correlation analysis showed that the predictive accuracy rate of the midsagittal diameter in LL simulated decompression was 93.8％(45/48).The preoperative C2-C7 Cobb angle of the 45 patients with accurate prediction were 24.2°±6.7°,and the postoperative C2-C7 Cobb angle was 24.2°±6.3°,and there was no statistically significant difference(P＞0.05).The 45 patients with accurate predictions were grouped with preoperative C2-C7 Cobb angles into 16 patients with Cobb＜20° and 29 patients with Cobb ≥ 20°.The mean midsagittal diameter of LL simulated and actual decompression in pa-tients with Cobb ≥ 20° was significantly greater than that in patients with Cobb＜20°(P＜0.05).In the three pa-tients with inaccurate prediction,the C2-C7 Cobb angle was significantly reduced postoperatively compared to preoperatively,and the actual midsagittal diameter of the dural sac after the operation was smaller than that in the LL simulated decompression(P＜0.05).All the 48 patients were followed up for 12 to 36 months(22.5±7.0 months),and the mJOA score at 12-month postoperative follow-up was 16.5±0.8 points,which was sig-nificantly higher than that before operation(P＜0.05).Conclusions:The application of MRI T2WI midsagittal LL simulated decompression before operation can well predict the effect of spinal cord decompression in cer-vical expansive open-door laminoplasty.

OBJECTIVE: To investigate the effectiveness of sagittal top compression reduction technique in the treatment of thoracolumbar vertebral fractures. METHODS: A retrospective analysis was conducted on the clinical data of 59 patients with thoracolumbar vertebral fractures who met the selection criteria and were admitted between November 2018 and January 2022. Among them, 34 patients were treated with sagittal top compression reduction technique (top pressure group), and 25 patients were treated with traditional reduction technique (traditional group). There was no significant difference in baseline data between the two groups ( P>0.05), including gender, age, fracture segment, cause of injury, AO classification of thoracolumbar vertebral fractures, thoracolumbar injury classification and severity (TLICS) score, American Spinal Injury Association (ASIA) grading, surgical approach, preoperative vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, segmental kyphosis angle, visual analogue scale (VAS) score, and Oswestry disability index (ODI). The operation time, intraoperative blood loss, and incidence of complications between the two groups were recorded and compared. After operation, VAS score and ODI were used to evaluate effectiveness, and X-ray and CT examinations were performed to measure imaging indicators such as vertebral body index, height ratio of the anterior margin of injured vertebra, injured vertebra angle, and segmental kyphosis angle. RESULTS: There was no significant difference in operation time and intraoperative blood loss between the two groups ( P>0.05). No complication such as dural sac, nerve root, or vascular injury was found during operation, and all incisions healed by first intention. Patients in both groups were followed up 6-48 months, with an average of 20.6 months. No loosening, breakage, or failure of internal fixation occurred during follow-up. The imaging indicators, VAS score, and ODI of the two groups significantly improved at 1 week and last follow-up when compared to preoperative ones ( P<0.05). At last follow-up, the VAS score and ODI further significantly improved when compared to 1 week after operation ( P<0.05). At 1 week after operation and last follow-up, the vertebral body index, segmental kyphosis angle, injured vertebra angle, and ODI in the top pressure group were significantly better than those in the traditional group ( P<0.05). There was no significant difference in VAS score and height ratio of the anterior margin of injured vertebra between the two groups at 1 week after operation ( P>0.05), but the two indicators in the top pressure group were significantly better than those in the traditional group at last follow-up ( P<0.05). CONCLUSION The treatment of thoracolumbar vertebral fractures with sagittal top compression reduction technique can significantly improve the quality of vertebral reduction, and is superior to traditional reduction techniques in relieving pain and improving spinal function.
Humans ; Thoracic Vertebrae/injuries* ; Lumbar Vertebrae/injuries* ; Retrospective Studies ; Blood Loss, Surgical ; Treatment Outcome ; Pedicle Screws ; Spinal Fractures/surgery* ; Kyphosis ; Fracture Fixation, Internal ; Fractures, Compression/surgery*