Early Therapeutic Effect Comparison Of Paraspinal Approach Combined With Internal Fixation Through Pedicle Of Fractured Vertebra And Traditional AF Screw - Rod System To Thoracolumbar Fractures

Thoracolumbar fracture accounts for about 50%of all spinal fractures.When the vertebral height compression is over 50%,or when the Cobb angle of thoracolumbar injured adjacent vertebra exceeds 20 degrees,active surgical treatment will be needed.Long-term bed of spinal fractures will cause complications such as pneumonitis,urinary tract infection and bedsore.Therefore,active surgical treatment has been one of the means to treat thoracolumbar fractures currently.For the moment,posterior short segment AF screw rod system of traditional stripping paraspinal muscle approach internal fixation of thoracolumbar fracture has become one of the main treatment,but the high failure rate of operation is getting more and more attention of scholars at home and abroad.In order to overcome the above drawbacks,since 1963,there has been a theoretical and experimental study on the treatment of thoracolumbar fractures with short segment pedicle screws,which has been gradually promoted.Some scholars like Finkelstein consider the short segment fixed reduction of the injured vertebral nail can reduce the loss of motor segment and obtain satisfactory short-term follow-up results.Some studies show that the paraspinal muscle gap approach does not need to strip the paraspinal muscles.It has the advantages of less trauma,less intraoperative blood loss and faster postoperative recovery,which will avoid extensive stripping of paraspinal muscles resulting in paravertebral muscle ischemia necrosis and denervation complications.At present,for thoracolumbar fractures without nerve compression symptoms,it is a safe and effective surgical treatment to remove the paraspinal muscle by AF screw rod system internal fixation of traditional posterior median approach.However,because of the extensive removal of paraspinal muscles and dragging of laminar hooks for long time,it is easy to cause ischemic necrosis and denervation of lumbar back muscles,resulting in chronic low back pain and non-ideal long-term effect.In1968,Wiltse and others proposed the muscle gap approach in the treatment of thoracolumbar fractures.After that,the domestic and foreign literature on this approach in the treatment of thoracolumbar fractures was widespread.It could greatly reduce the stripping of the paraspinal muscles and ligaments of soft tissue,and shorten the hospitalization time,with characteristics of shorter operation time as well as less bleeding.In 1994,Dick and others began to study the treatment of thoracolumbar fractures with short segment pedicle screws.Then the domestic and foreign literature indicated the functions of vertebral pedicle screw as follows:?1?It contributes to the direct reduction of vertebral injury,rather than the indirect reduction of the AF screw through anterior longitudinal ligament;?2?It gives the injured vertebra a direct impetus,which is better for thoracolumbar fractures caused by the kyphosis;?3?The traditional AF screw system is to use the 4 pin reset through the anterior longitudinal ligament,while the 6 pin reset after injured vertebra fixation will change the vertebral strength from"1"to"2",which helps disperse the screw rod stress and reduces the occurrence of broken nail.Yuan Qiang^[17]believes that there are several changes of curative effect of injured vertebra fixation,they are,?1?AF system for screw fixation of four points is prone to parallelogram effect,while six point fixation of injured vertebra will reduce the parallelogram effect and increase the fixation stability;?2?The traditional AF screw rod system helps achieve indirect reduction by using the function of the anterior longitudinal ligament through the two adjacent vertebrae of the injured vertebra,which increases the stress of adjacent intervertebral disc,while the injured vertebra fixation reduces the stress on the adjacent disc,preventing the aggravation of adjacent disc degeneration.This study further confirms that intermuscular space approach combined with pedicle screw fixation for thoracolumbar fractures can fully protect the paraspinal muscle tissue and reduce postoperative pain.It can better restore the physiological curvature of thoracolumbar spine and the height of injured vertebrae.The operation bleeding and the operation time are significantly reduced,but the initial surgical bleeding and the surgical time haven't been reduced significantly compared with the control group.This is probably due to the unskilled operation of muscle gap approach.To be specifically,the multifidus and longissimus muscle clearance cannot be found accurately in the operation,which will prolong the operation time and increase the amount of bleeding.With the increase in the number of surgical cases,the operation time and the blood loss are significantly lower than the control group.Objective:This study is to compare rehabilitation of patients with thoracolumbar fracture after operation,and to compare the clinical effects of intermuscular space approach combined with short segment internal fixation and traditional AF screw rod system for thoracolumbar fracture.Methods:96 patients of thoracolumbar fracture from July 2009 to June 2014?according to the inclusion and exclusion criteria?were randomly divided into two groups.Group A?42 cases?were treated by intermuscular space approach combined with short segment internal fixation,while Group B?54 cases?were treated with traditional AF screw rod system.The operative time,intraoperative blood loss,postoperative drainage volume,postoperative internal fixation reduction?fracture vertebral reduction rate,vertebral column Cobb angle of injured vertebra?,and the improvement of self-symptom?pain analogue visual VAS score?were recorded and evaluated in the two groups.Results:All the 96 patients had operations successfully,including 78 males and 18females,and the sex ratio was 4.33:1.?² test indicated that there was no significant difference in the gender distribution between the two groups??²=0.004,P>0.05?,and there was no significant difference in the location of injury??²=1.836,P>0.05?,either.Group A was followed up for 8¹2 months with an average of 10.4 months,and Group B was followed up for 8¹4 months with an average of 14.1 months.The average age of Group A was 42.36+11.212 years old,with the preoperative Cobb angle being 29.14°+9.702°and the preoperative VAS score being 5.71+1.111.Group B had an average age of 41.26+10.669 years old,with the preoperative Cobb angle being 28.09°+6.181°and the preoperative VAS score being 5.43+1.075.T test showed no significant difference in age,preoperative Cobb angle and preoperative VAS score between the two groups.And it also showed there was no significant difference between the two groups in the operation time?t=1.627,P>0.05?.But the amount of bleeding?t=5.579,P<0.05?and the postoperative drainage?t=2.468,P<0.05?had significant difference.To be specifically,both the amount of bleeding and the postoperative drainage of Group A were less than those of Group B.T test for the last follow-up indicated that there was significant difference between Group A and Group B in the postoperative Cobb angle of injured adjacent vertebrae?t=6.239,P<0.05?,the improvement angle?t=2.086,P<0.05?and the postoperative VAS score?t=2.287,P<0.05?.Specifically,the postoperative Cobb angle of injured adjacent vertebrae of Group A was significantly less than that of Group B,the improvement angle of Group A was better than that of Group B,and the postoperative VAS score of Group A was significantly lower than that of Group B.Besides,?² test showed that there was no statistical significance in preoperative relative height of injured vertebrae between Group A and Group B??²=1.426,P>0.05?,while there was statistical significance between the two groups in postoperative relative height??²=3.048,p<0.05?.And Group A?94.901%+2.373%?was better than Group B?93.093%+3.429%?in this aspect.The difference in reduction rate of vertebral fracture between the two groups was statistically significant??²=3.520,p<0.05?,and group A?89.428%+4.787%?was better than Group B?84.709%+8.222%?.The significant improvement rate of Group A was higher than that of Group B.Compared to Group B,Group A could better restore the vertebral height of injured vertebrae and maintain the physiological curvature of the thoracolumbar?Figure 1,2?.In the postoperative evaluation of neurological function,there were 5 cases of grade D and37 cases of grade E in Group A,while 16 cases of grade D and 38 cases of grade E in Group B.ASIA grade had no statistically significant difference between Group A and B before surgery??²=0.596,P>0.05?,but the difference was statistically significant after surgery??²=4.343,P<0.05?.The nerve function improvement of Group A was better than that of Group B.There were 2 cases?3.70%,2/54?of internal fixation screw withdrawing and 3 cases?5.56%,3/56?of internal fixation screw fracture after surgery in Group B,while there were no internal fixation loosening and breaking in Group A.During the follow-up period,there were no complications such as wound infection found in the two groups.Conclusion:Both the intermuscular space approach combined with short segment internal fixation and traditional AF screw rod system have a certain clinical effect in the treatment of thoracolumbar fracture.In comparison with traditional AF screw rod system,the intermuscular space approach combined with short segment internal fixation has a better performance in postoperative lumbar kyphosis,nail withdrawal rate and correction of thoracolumbar kyphosis.