ObjectiveTo compare the effectiveness of treatment of isthmic spondylolisthesis between two different fusion surgeries combined with pedicle screw fixation system. MethodsA retrospectively analysis was made on the clinical data of 98 patients with lumbar isthmic spondylolisthesis treated between February 2009 and May 2012. Of 98 cases, 53 underwent posterior lumbar interbody fusion (PLIF) combined with internal fixation (group A), and 45 underwent posterolateral fusion (PLF) with internal fixation (group B). There was no significant difference in gender, age, disease duration, segmental lesions, and degree of spondylolisthesis between 2 groups (P>0.05). The operation time, intraoperative blood loss, reduction rate of spondylolisthesis, reduction loss rate, fusion rate, intervertebral space height, Japanese Orthopedic Association (JOA) score, and the recovery rate of JOA score were compared between 2 groups. ResultsThe operation time and intraoperative blood loss of group A were significantly higher than those of group B (P<0.05). Dural tear occured in 4 cases of group A and 1 case of group B during operation; 6 cases had radicular symptoms after operation in group A; incision infection was found in 1 case of 2 groups respectively. The follow-up time was 24-36 months in group A and was 26-40 months in group B. No significant difference was found in the JOA score at preoperation and 2 weeks after operation between 2 groups (P>0.05). The JOA score and the recovery rate of JOA score of group A were significantly better than those of group B at 2 years after operation (P<0.05). X-ray film showed that the reduction rate of group A was significantly higher than that of group B after 2 weeks of operation (P<0.05); the reduction loss rate of group A was significantly lower than that of group B after 2 years after operation (P<0.05). The intervertebral space height of group A was significantly higher than that of group B at 2 weeks and 2 years after operation (P<0.05). The fusion rate of group A was significantly better than that of group B at 2 years after operation (P<0.05). ConclusionPLIF can achieve a greater degree of reduction, better restore disc height, and lumbar curvature than PLF. PLIF is superior to PLF in maintaining intervertebral height after operation. And PLIF has higher fusion rate, restores the stability of the spine in a greater extent, and it also can achieve a better long-term outcome.
Objective To investigate the effect of the sagittal alignment of the spine and pelvis after surgical posterior intervertebral fusion combined with pedicle screw fixation for low-grade isthmic lumbar spondylolisthesis, and to assess the effectiveness. Methods Between October 2009 and October 2011, 30 patients with low-grade isthmic spondylolisthesis underwent surgical posterior intervertebral fusion combined with pedicle screw fixation, and the clinical data were retrospectively reviewed. There were 14 males and 16 females with an average age of 56.7 years (range, 48-67 years). The pre- and post-operative radiographic parameters, such as percentage of slipping (PS), intervertebral space height, angle of slip (AS), thoracic kyphosis (TK), thoracolumbar junction angle (TLJ), sagittal vertical axis (SVA), lumbar lordosis (LL), spino-sacral angle (SSA), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI) were measured. The functional evaluation was made using the Oswestry Disability Index (ODI). Pearson correlation were used to investigate the association between all parameters and ODI score. Results PS, intervertebral space height, AS, and ODI were improved significantly compared with properative ones (P lt; 0.05). Significant differences were found in the other parameters between pre- and post-operation (P lt; 0.05) except TLJ and TK. The alteration of SVA showed significant correlation with the changes of PS, PI, PT, LL, SS, AS, SSA, and ODI. The alteration of SSA showed significant correlation with the changes of PS, PI, LL, SS, AS, PT, and ODI. Conclusion Surgical posterior intervertebral fusion combined with pedicle screw fixation for low-grade isthmic spondylolisthesis can effectively improve and maintain the spinal sagittal parameters. SVA and SSA are adequate to evaluate pre-and post-operative balance. The good clinical outcome is closely related with the improved of SVA and SSA.
Objective To analyze the effectiveness of combined treatment of lumbar spondylolisthesis with MED, Quadrant, and Sextant-R systems. Methods Between August 2006 and June 2011, 35 patients with lumbar spondylolisthesis were treated, including 11 cases of isthmic spondylolisthesis and 24 cases of degenerative spondylolisthesis. There were 25 males and 10 females, with a mean age of 55 years (range, 33-71 years). The mean disease duration was 37 months (range, 8-75 months). Spondylolisthesis occurred at L4, 5 level in 21 patients and at L5, S1 level in 14 patients. According to Meyerding classification, 35 cases were rated as dergee I. The minimally invasive surgeries were performed by paraspinal muscle approach; Quadrant system was used for decompression and fusion at severe side, MED system for windowing of lamina at mild side, and Sextant-R system for fixation and reduction. Visual analogue scale (VAS) score was used to evaluate pain, Oswestry disability index (ODI) to evaluate clinical outcomes, spondylolishesis ratio and intervertebral height to evaluate spondylolisthesis reduction. Results Lumbar continuous thin layer CT at postoperation showed that no pedicle screw invaded spinal canal and intervertebral fusion device was at good position. Incisions healed by first intention. All patients were followed up 18-38 months (mean, 26 months). All patients got bone fusion and had no internal fixation failure by radiologic examination at 1 year after operation. Low back pain was relieved, lumbar function improved obviously, and satisfactory reduction of spondylolisthesis was obtained. At 2 weeks and 1 year after operation, the VAS score, ODI score, spondylolisthesis ratio, and intervertebral height were significantly improved when compared with preoperative ones (P lt; 0.05). VAS score and ODI score showed significant differences (P lt; 0.05) between at 2 weeks and 1 year after operation. Spondylolisthesis ratio and intervertebral height showed no significant difference (P gt; 0.05) between at 2 weeks and at 1 year after operation. Conclusion Minimally invasive surgical management for lumbar spondylolisthesis via MED, Quadrant, and Sextant-R systems is a safe and effective surgical technique. However, its indications should be well considered.
Objective To investigate the technique of reduction by posterior approach for severe spondylolisthesis, and to discuss the method to prevent nerve stretch injury. Methods Between July 2007 and April 2011, 17 patients with severe spondylolisthesis underwent reduction, fixation, and fusion by posterior approach. There were 2 males and 15 females with a median age of 15 years (range, 8-67 years) and a median disease duration of 18 months (range, 5 months-16 years and 4 months). The level of spondylolisthesis was at L4 in 1 case and L5 in 16 cases; the spondylolisthesis was at degree III in 12 cases and degree IV in 5 cases according to Meyerding classification. There were 16 cases of developmental spondylolisthesis (high- dysplastic and low-dysplasia spondylolisthesis in 9 and 7 cases, respectively) and 1 case of traumatic spondylolisthesis; 16 cases of developmental spondylolisthesis at L5 level included 6 cases of type 4, 9 case of type 5, and 1 case of type 6 according to Spinal Deformity Study Group (SDSG) classification. All cases underwent posterior spinal decompression, Schanz screw fixation for the slipped vertebrae, the intervertebral and posterolateral fusion and reduction of the slipped vertebrae, and correction of the lumbosacral kyphosis. The reductive degree of slipped vertebrae was modulated according to the strain of exiting spinal root. The slip degree should be reduced within Meyerding degree II. The anteroposterior and lateral radiographs of whole spine were taken in a standardized standing position to observe the correction of displacement severity and lumbosacral angle. The nerve function and pain score of lower extremity were evaluated by neurological Frankel grade and visual analogue scale (VAS). Bony fusion was assessed by followed-up CT three-dimentional reconstruction. Results Exiting nerve root paralysis occurred in 1 case after operation, and released at 4 weeks after operation; no aggravation of nerve damage was observed in the other patients. The incisions primarily healed. All the patients were followed up 12-48 months (mean, 25 months). The slip percentage, the lumbosacral angle, and VAS score of lower extremity were improved from 72% ± 10%, (18.2 ± 3.5)°, and 7.0 ± 1.5 at preoperation to 12% ± 6%, ( — 7.3 ± 2.9)°, and 1.5 ± 1.3 at 12 months after operation respectively, all showing significant differences (P lt; 0.05). Osteosynthesis was seen at the bone grafting area by CT three-dimentional reconstruction at 12 months after operation. No breakage of screw and rod or reduction loss occurred. Conclusion It can obtain satisfactory clinical result to use spinal canal decompression by posterior approach, the Schanz screw fixation of the slipped vertebrae, the intervertebral and posterolateral fusion for severe spondylolisthesis. The risk of nerve stretch injury can be prevented by choosing the lowest height of intervertebral cage, modulating the reductive degree of slipped vertebrae according to the strain of exiting spinal root, and correcting lumbosacral kyphosis.
Objective To review the research progress of the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis, and to discuss the value of Spinal Deformity Study Group (SDSG) classification system for lumbosacral spondylolisthesis. Methods Recent articles about the risk factors for slip progression and the pathogenesis of lumbosacral spondylolisthesis were reviewed and comprehensively analyzed with SDSG classification system of lumbosacral spondylolisthesis. Results Pelvic incidence (PI) is the key pathogenic factor of lumbosacral spondylolisthesis. The Meyerding grade of slip, PI, sacro-pelvic balance, and spino-pelvic balance not only are the fundamental risk factors of slip progression, but also are the key factors to determine how to treat and influence the prognosis. Therefore, compared with Wiltse, Marchetti-Bartolozzi, and Mac-Thiong-Labelle classification systems of lumbosacral spondylolisthesis, SDSG classification based on these factors mentioned above, has better homogeneity between the subjects of subgroup, and better reliability, moreover, could better guide operative plan and judge the prognosis. Conclusion It is suggested that the SDSG classification system should be the standard classification for lumbosacral spondylolisthesis for the clinical and research work.
To investigate the shortsegment pedicle screw in treating degenerative L4 spondylolisthesis and the relationship of the preliminarily bending degree of the titanium rod with the lumbar lordosisangle, the slipping angle and the slipping percentage and to evaluate the clinical coincidence and curative effects of the preliminarilybent rod. MethodsFrom September 2005 to March 2007, 31 female patients (age, 40-70 years; average, 58.3 years) were admitted for surgical treatment of their L4 degenerative spondylolisthesis (MeyerdingⅠ°, Ⅱ°)． Their lumbar lordosis angle （x1）, slipping angle (x2), and slipping percentage (x3) were measured in the L4,5 segment before operation. During the operation, the titanium rod bent beforehand according to the corresponding standards was inserted. The angle of the bent rod (Y) was measured, and then the multiple linear regression equation was established. The regression equation was applied to the surgical treatment of the 30 patients.Results According to the criteria in the JOA scoring system, the 31 patients had scores of 8.300± 1.080 and 26.916±1.859 before operation and after operation, respectively. There was a significant difference between before operation and after operation（Plt;0.05）. The established multiple linear regression equation was as follows:Y=0.1390-0.327logx1+0.463x2+0.288x32．The operating time was 51.290±3.408 min in the 30 patients who underwent an insertion of the preliminarilybent rod during the operation; however, the operating time was 102.360±5.004 min in the 31 patients who underwent an insertion of the bent rod that was made based on experience during the previous operations. There was a significant difference in the operating time between the two kinds of the rods （Plt;0.05）. Estimated according to 90%, 95% and 99% of the areas under the normalcurve, the clinical coincidence rates in the preliminarily bending degrees of the titanium rod in the 30 patients were 80.00％，90.00％ and 96.67％, respectively.Conclusion The titanium rod that has been bent into a certain angle before operation according to the established criteria can definitely diminish its strain during operation and efficiently shorten the operating time．Thiskind of the titanium rod has a good coincidence in clinical application and can be effectively used in clinical practice.It is worth reference during the clinical operation.
Objective To evluate the clinical outcome of autograftsof ilium and interbody fusion cage or bone morphogenetic protein(BMP)／artificial bone material／ cage in treating lumbar spondylolisthesis. Methods From January 1997 to January 2004，114 patients with lumbar spondylolisthesis were treated with posterior lumbar interbody fusion and pedicle screw fixation． There were 45 males and 69 females with an average age of 43 years ranging from 32 to 61 years. Of 114patients, 85 cases were classified as degree Ⅰ, 24 cases as degree Ⅱ and 5 cases as degree Ⅲ. The patients were divided into three groups accordingto the material used for interbody fusion: autografts of ilium (group A, n=42), interbody fusion cages(group B, n=36), and BMP／artificial bone material／ cage (group C, n=36)．The clinical and radiographic results of the patients were compared among three groups． Results All patients were followed from 13 to 30 months with an average of 15 months． There were no statistically significant differences in surgical time, blood loss, and disc space height of preoperation(P＞0.05) among three groups. No severe complication occurred in the three groups(P＞0.05). The excellent and good rates in groups A，B and C were 81.0％, 80.6％, and 83.3％ respectively, showing no statisticallysignificant difference(P＞0.05)．The fusion rate of group C(97.0%) was significantly higher than those of group A(81.0%) and group B(83.3%) (P＜0.05) after 1 year of operation．And the average loss of disc space height in groups B and C was significantly lower than that in group A(P＜0.05). Conclusion Higher fusion rate and lower loss of disc space height can beobtained in treating lumbar spondylolisthesis with BMP／artificial bone materiel.It is an effective method in the treatment of spondylolisthesis.
Objective To analyze the therapeutic effect of the posterior pedicle screw system combined with interbody fusion cage on lumbarspondylolisthesis. Methods From February 2003 to March 2006, 37 lumbar spondylolisthesis patients were treated with this operation, including21 males and 16 females and aging 3969 years.The affected lumbars were L3(3cases)，L4(23 cases), and L5(11 cases). According to the Meyerdingevaluating system, 12 cases were lassified as degree Ⅰ, 20 cases as degree Ⅱ,and 5 cases as degree Ⅲ. Taillard index, Boxall index, slipping angle, lumbar lordosis angle and intervertebral height index were measured before operation, and 2 weeks and 3 months after operation. Results All patients were followed up 336 months. There were statistically significant differences in Taillard index, Boxall index, slipping angle, lumbar lordosis angle and intervertebral height index between before operation and 2 weeks after operation (P＜0.05),and no statistically significant differences between 2 weeks and 3 months afteroperation(P＞0.05). According to Dewei Zhou’s creterior for scoring, the results were excellent in 27 cases， good in 8 cases，and fair in 2 cases. Theexcellent and good rate was 94.6%. All of the embedded osseous were fused. Thefusing time was from 3 to 8 months (mean 3-9 months). There were no breakageof screw and rod. The position and configuration of the whole cages were good. Conclusion Applying the posterior pedicle screw system combined with interbody fusion cage may achieve synergism in the treatment of lumbar vertebral spondylolisthesis. Above procedure is served as solid internal fixationand offers a satisfactory reduction, and can improve the fusion rate of the spine. So it is an ideal procedure and worthily recommended method for treatment oflumbar vertebral spondylolisthesis.
Objective To compare the clinical outcomes of posterior lumbar interbody fusion（PLIF） using simple cage alone fusion with pedicle screw fixationand autogenous bone grafting and cage fusion with pedicle screw fixation in adult spondylolisthesis. Methods From March 2003 to March 2004，Twenty-seven patients with lumbar spondylolisthesis were divided in two groups. In group A, 15 patients were treated by PLIF using simple cage alone fusion with pedicle screw fixation, including 4 males and 11 females, aging 53-68 years. Isthmic defectswere located at L4 in 9 cases, at L5 in 6 cases. Four patients were smokers.Thepreoperative mean disc space height was 5.4±2.3 mm, the mean percentage of slip was 36.8％±7.2%. In group B, 12 patients were treated by PLIF using autogenous bone grafting and cage fusion with pedicle screw fixation, including 3 males and 9 females, aging 56 years. Isthmic defects were located at L4 in 8 cases, atL5 in 4 cases. Five patients were smokers. The preoperative mean disc space height was 5.7±2.5 mm, the mean percentage of slip was 37.8%±6.2%. Two groupswere compared in the amount of blood loss, duration of hospitalization, back pain, radiating pain, fusion rate, the intervertebral disc space height, the postoperative degree of slip and the fusion rate. Results All patientswere followed up for 24-38 months. The mean follow-up was 29(24-36) months in group A and26(24-38) months in group B. There were no statistically significant differences infollow-up period, age,sex, the location of isthmic defects, smoking, the preoperative disc space height and the percentage of slip between two groups (Pgt;0.05).There were no statistically significant differences in the amount of blood loss, the duration of hospitalization, the fusion time between two groups(Pgt;0.05). But there were statistically significant differences in the back pain score, the radiating pain score and the fusion rate between two groups(Plt;0.05).Thepo stoperative disc space height and the degree of slip of the last follow-up were5.8±2.2 mm and 25.6％±7.2% in group A, 6.2±2.5 mm and 24.1％±7.4 % ingroupB, showing statistically significant difference (Plt;0.05). Conclusion The PLIF using autogenous bone grafting and cage fusion with pedicle screw fixations ismore beneficial to improving the fusion rate and preventing longterm instabilities than simple cage alone fusion with pedicle screw fixation in adult spondylolisthesis.
BJECTIVE: To discuss the clinical effect and the application of AF device fixation system and PROSPACE interbody fusion cage on treating lumbar spondylolisthesis. METHODS: Twenty-one cases of lumbar spondylolisthesis treated by operation from 1999 to 2002 were analyzed retrospectively (13 males and 8 females, 25-66 years old averaging 42 years). We had thorough decompression on the part of nerve compression and had replacement and fixation of the slippage vertebral body with the AF transpedicular screw/rod system so that the normal spine physiological curvature could be recovered, and then performed the posterolateral interbody fusion with implanting the PROSPACE filled with autograft bones. RESULTS: All the patients were followed up for 3 months to 3 years with an average of 15 months. The preoperation symptoms improved in 20 cases (95.2%). CONCLUSION: The combination of AF device fixation system and PROSPACE interbody fusion cage can relieve effectively nerve compression, recover the normal spinal physiological curvature, maintain the height of interbody and promote the nerve fusion. It is reliable and effective in the treatment of spondylolisthesis.