Objective To evaluate surgical strategy of decompression via posterior-anterior approach and anterior fixation in treatment fracture-dislocation of lower cervical spine with bilateral facet joints dislocation. Methods...Objective To evaluate surgical strategy of decompression via posterior-anterior approach and anterior fixation in treatment fracture-dislocation of lower cervical spine with bilateral facet joints dislocation. Methods This展开更多
Background: It has been accepted amongst rheumatologists that rheumatoid arthritis (RA) does not involve the facet joints (FJs) of the spine;nevertheless, the issue is still under debate. Objective: To compare the pre...Background: It has been accepted amongst rheumatologists that rheumatoid arthritis (RA) does not involve the facet joints (FJs) of the spine;nevertheless, the issue is still under debate. Objective: To compare the prevalence of FJs’ changes between patients with RA and age- and sex-matched peers. Methods: CT scans of 34 patients with RA suffering from low back pain (LBP) were compared with 70 age- and sex-matched controls (individuals without RA, suffering from LBP) in a case-control study. The degenerative changes in the FJs were evaluated (i.e., joint space narrowing, marginal osteophytes, articular process hypertrophy, subchondral sclerosis, inter-joint vacuum phenomenon, and subchondral cysts), in addition to the marginal erosions, the most characteristic feature of joint change in RA. Disease activity characteristics (CRP, ESR, DAS-28, SDAI, and CDAI), duration of RA, age, and sex were obtained from patients’ clinical charts. Results: The prevalence of FJs’ changes in patients with RA and age- and sex-matched controls were not significantly different at any spinal level or in a total L1-S1 score. Marginal erosions, a characteristic feature of joint changes in RA, were not found in any of our RA subjects. No difference was found in disease parameters and markers in individuals with RA with affected FJs and those without. The occurrence of FJs’ changes amongst subjects with RA demonstrated no correlation with disease duration and activity. Conclusions: FJs of the lumbar spine are not involved in the inflammatory process of RA, and their LBP is not due to inflammation in FJs of the spine.展开更多
Background Percutaneous pedicle screw use has a high rate of cranial facet joint violations （FVs） because of the facet joint being indirectly visualized.Computer-assisted navigation shows the anatomic structures cle...Background Percutaneous pedicle screw use has a high rate of cranial facet joint violations （FVs） because of the facet joint being indirectly visualized.Computer-assisted navigation shows the anatomic structures clearly,and may help to lower the rate of FVs during pedicle screw insertion.This study used computed tomography （CT） to evaluate and compare the incidence of FVs between percutaneous and open surgeries employing computer-assisted navigation for the implantation of pedicle screw instrumentation during lumbar fusions.Methods A prospective study,including 142 patients having lumbar and lumbosacral fusion,was conducted between January 2013 and April 2014.All patients had bilateral posterior pedicle screw-rod instrumentation （top-loading screws） implanted by the same group of surgeons; intraoperative 3-dimensional computer navigation was used during the procedures.All patients underwent CT examinations within 6 months postoperation.The CT scans were independently reviewed by three reviewers blinded to the technique used.Results The cohort comprised 68 percutaneous and 74 open cases （136 and 148 superior-level pedicle screw placements,respectively）.Overall,superior-level FVs occurred in 20 patients （20/142,14.1％）,involving 27 top screws （27/284,9.5％）.The percutaneous technique （7.4％ of patients,3.7％ of top screws） had a significantly lower violation rate than the open procedure （20.3％ of patients,14.9％ of top screws）.The open group also had significantly more serious violations than did the percutaneous group.Both groups had a higher violation rate when the cranial fixation involved the L5.A 1-level open procedure had a higher violation rate than did the 2-and 3-level surgeries.Conclusions With computer-assisted navigation,the placement of top-loading percutaneous screws carries a lower risk of adjacent-FVs than does the open technique; when FVs occur,they tend to be less serious.Performing a single-level open lumbar fusion,or the fusion of the L5-S1 segment,requires caution to avoid cranial adjacent FVs.展开更多
目的研究不同大小随动载荷在腰椎不同姿态下对小关节接触力的影响。方法建立非线性三维有限元腰椎模型(L1~S1),并考虑小关节软骨的非均一厚度和非线性材料特征。对腰椎模型施加不同大小的随动力预载荷(0、0.5、0.8、1.2 k N)以及7.5 N&#...目的研究不同大小随动载荷在腰椎不同姿态下对小关节接触力的影响。方法建立非线性三维有限元腰椎模型(L1~S1),并考虑小关节软骨的非均一厚度和非线性材料特征。对腰椎模型施加不同大小的随动力预载荷(0、0.5、0.8、1.2 k N)以及7.5 N·m不同方向上(前屈、后伸、侧弯、轴向旋转)的纯力矩,对比各运动节段两侧小关节上在不同加载工况下的接触力,并定量研究随动载荷对小关节不对称性的影响。结果随动载荷的应用会增大屈伸以及侧弯(同侧)状态下的小关节接触力,而减少侧弯(对侧)时的小关节接触力,而且这种增大(或减小)效应会随着随动载荷本身的增大而减弱。对于轴向扭转,预载荷对小关节力几乎没有影响。在腰椎不同的姿态下,随动载荷对于小关节接触力不对称性的影响按从大到小排列依次为:侧弯(同侧)、前屈、侧弯(对侧)、后伸、轴向扭转。结论随动载荷对腰椎小关节接触力的影响随腰椎运动姿态的不同而不同。在腰椎的生物力学研究中,小关节的不对称性需要被充分考虑,尤其是在生理载荷作用下腰椎后部结构的研究中。展开更多
文摘Objective To evaluate surgical strategy of decompression via posterior-anterior approach and anterior fixation in treatment fracture-dislocation of lower cervical spine with bilateral facet joints dislocation. Methods This
文摘Background: It has been accepted amongst rheumatologists that rheumatoid arthritis (RA) does not involve the facet joints (FJs) of the spine;nevertheless, the issue is still under debate. Objective: To compare the prevalence of FJs’ changes between patients with RA and age- and sex-matched peers. Methods: CT scans of 34 patients with RA suffering from low back pain (LBP) were compared with 70 age- and sex-matched controls (individuals without RA, suffering from LBP) in a case-control study. The degenerative changes in the FJs were evaluated (i.e., joint space narrowing, marginal osteophytes, articular process hypertrophy, subchondral sclerosis, inter-joint vacuum phenomenon, and subchondral cysts), in addition to the marginal erosions, the most characteristic feature of joint change in RA. Disease activity characteristics (CRP, ESR, DAS-28, SDAI, and CDAI), duration of RA, age, and sex were obtained from patients’ clinical charts. Results: The prevalence of FJs’ changes in patients with RA and age- and sex-matched controls were not significantly different at any spinal level or in a total L1-S1 score. Marginal erosions, a characteristic feature of joint changes in RA, were not found in any of our RA subjects. No difference was found in disease parameters and markers in individuals with RA with affected FJs and those without. The occurrence of FJs’ changes amongst subjects with RA demonstrated no correlation with disease duration and activity. Conclusions: FJs of the lumbar spine are not involved in the inflammatory process of RA, and their LBP is not due to inflammation in FJs of the spine.
文摘Background Percutaneous pedicle screw use has a high rate of cranial facet joint violations （FVs） because of the facet joint being indirectly visualized.Computer-assisted navigation shows the anatomic structures clearly,and may help to lower the rate of FVs during pedicle screw insertion.This study used computed tomography （CT） to evaluate and compare the incidence of FVs between percutaneous and open surgeries employing computer-assisted navigation for the implantation of pedicle screw instrumentation during lumbar fusions.Methods A prospective study,including 142 patients having lumbar and lumbosacral fusion,was conducted between January 2013 and April 2014.All patients had bilateral posterior pedicle screw-rod instrumentation （top-loading screws） implanted by the same group of surgeons; intraoperative 3-dimensional computer navigation was used during the procedures.All patients underwent CT examinations within 6 months postoperation.The CT scans were independently reviewed by three reviewers blinded to the technique used.Results The cohort comprised 68 percutaneous and 74 open cases （136 and 148 superior-level pedicle screw placements,respectively）.Overall,superior-level FVs occurred in 20 patients （20/142,14.1％）,involving 27 top screws （27/284,9.5％）.The percutaneous technique （7.4％ of patients,3.7％ of top screws） had a significantly lower violation rate than the open procedure （20.3％ of patients,14.9％ of top screws）.The open group also had significantly more serious violations than did the percutaneous group.Both groups had a higher violation rate when the cranial fixation involved the L5.A 1-level open procedure had a higher violation rate than did the 2-and 3-level surgeries.Conclusions With computer-assisted navigation,the placement of top-loading percutaneous screws carries a lower risk of adjacent-FVs than does the open technique; when FVs occur,they tend to be less serious.Performing a single-level open lumbar fusion,or the fusion of the L5-S1 segment,requires caution to avoid cranial adjacent FVs.
文摘目的研究不同大小随动载荷在腰椎不同姿态下对小关节接触力的影响。方法建立非线性三维有限元腰椎模型(L1~S1),并考虑小关节软骨的非均一厚度和非线性材料特征。对腰椎模型施加不同大小的随动力预载荷(0、0.5、0.8、1.2 k N)以及7.5 N·m不同方向上(前屈、后伸、侧弯、轴向旋转)的纯力矩,对比各运动节段两侧小关节上在不同加载工况下的接触力,并定量研究随动载荷对小关节不对称性的影响。结果随动载荷的应用会增大屈伸以及侧弯(同侧)状态下的小关节接触力,而减少侧弯(对侧)时的小关节接触力,而且这种增大(或减小)效应会随着随动载荷本身的增大而减弱。对于轴向扭转,预载荷对小关节力几乎没有影响。在腰椎不同的姿态下,随动载荷对于小关节接触力不对称性的影响按从大到小排列依次为:侧弯(同侧)、前屈、侧弯(对侧)、后伸、轴向扭转。结论随动载荷对腰椎小关节接触力的影响随腰椎运动姿态的不同而不同。在腰椎的生物力学研究中,小关节的不对称性需要被充分考虑,尤其是在生理载荷作用下腰椎后部结构的研究中。
