One Stage Operation Anterior-posterior Approach In The Treatment Of Acute Cervical Hyperextension Injury Combined Cervical Canal Stenosis

There were no symptoms or few symptoms in the patients with cervical hyperextension injury combined cervical canal stenosis before injury , but the spinal cord functions could be severely impaired by only minor forces that resulted in paresis, quadriplegia and even death.The static compression of the spinal cord by cervical stenosis was the primary factor for cervical myelopathy. However, dynamic factors for trauma also contributed to nerological deficits in the cervical stenosis. There were no fracture and dislocation of cervical spine in the majority of patients at X-ray. MRI scans was useful to understand the levels, the degree, and the mechanism of the injuried spine by the abnormal signals of paraspinal soft tissues, discs, and the spinal cord injury.There were 35 patients diagnosed for cervical hyperextension injury and cervical canal stenosis, 12 patients were treated through one stage operation for anterior and posterior decompression. After operation patients were follow-up for post-operation,one month,three months,one year and according to JOA standard spinal cord function were evaluated, the recovery rate=Post-op JOA score-pre-op JOA score/17-pre-op JOA score. t test was applied to detect the differences between pre-op and post-op in the sagittal diameter of spinal canal. The analysis of variance was used to detect the differences in JOA score at multiple time points and P value less than 0.05 was considered significant. Cervical canal sagittal diameter,cervical cord sagittal diameter,the distance of spinal cord shift were measured in pre-op and post-op, and correlation among them was evaluated and analysed. Correlation regression analysis was performed among them, and P value less than 0.05 was considered significant. The operation was done by one person. All cases were follow-up for one year. Clinical results, including JOA score,cervical cord sagittal diameter,the distance of spinal cord shift,laminoplasty opening size in pre-op and post-op,Operation time and blood loss amounts were calculated and analysed statistically.Two years were follow-up post-op and recheck regularly. Fill the form according to JOA score and calculate recovery rate. JOA score and recovery rate were improved significantly after post-op, especially after one year. The average recovery rate of spinal cord which was higher than it in pro-op were 22.5%, 33.7%, 42.4%, 55.6%. A rapid improvement in JOA score and recovery rate was noted from pre-op to post-op one year, and a steady improvement in JOA score and recovery rate was noted from one year to two years. The variation of spinal canal sagittal diameter: The spinal canal sagittal diameter increased from pro-op 10.1±1.2(mm) to post-op 18.1±0.7(mm). t test was applied to detect the differences between pre-op and post-op in the sagittal diameter of spinal canal. The correlation between increased spinal canal sagittal diameter and spinal cord shift,increased dura matter diameter: the distance of spinal cord shift and increased dura matter diameter were measured 6.3±0.8(mm) and 7.2±0.9(mm) after post-op. Significant positive correlation was found between increased spinal canal diameter and increased dura matter , R=0.816(P<0.01). But significant positive correlation was not found between increased spinal canal diameter and spinal cord shift, R=0.425(P<0.01). MRI scans demonstrated that sufficient decompression of the spinal cord at the expanded levels was vertified. CT revealed that fused segments gained the bony fusion and internal fixation was intact after 8 months .The closure of the the opened lamina did not arised at follow-up periods and bone grafting was fixed tightly. All the operation were performed by one surgeon. Operation time was 90min±25min and blood loss amounts was 300ml±60ml.In all, One stage operation of anterior and posterior approach are performed in the treatment of the acute cervical hyperextension injury presenting cervical stenosis , and effectively reconstructs the cervical stabilization and expands the sagittal diameter of spinal canal at the same time. The patients who had neurological deficits after heads and faces injuries with no fracture and dislocation had better take MRI scans to understand the degree of cervical injuries that provided more informations for the choices of treatment and prognosis judgement. Significant positive correlation was found between increased spinal canal diameter and increased dura matter, and significant positive correlation was not found between increased spinal canal diameter and spinal cord shift. The results showed that there is a very high correlation between laminoplasty opening size and the increased size of the spinal canal, thus indicating the amount of canal expansion following laminoplasty can be predicted by afore-mentioned equations. It can make operation procedure quantization and fineness and have a guided significance for operation procedure.