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Objective:To compare the postoperative adjacent segment degeneration (ASD) between the microscopically anterior cervical discectomy with fusion (ACDF) and anterior cervical corpectomy with fusion (ACCF) in the treatment of cervical spondylotic myelopathy and its influencing factors.Methods:Fifty patients with cervical spondylotic myelopathy treatment in the Qinzhou Second People′s Hospital from July 2018 to July 2020 were selected, they were divided into two groups, 25 patients performed ACDF (ACDF group), and 25 patients performed ACCF (ACCF group). The perioperative period, efficacy and incidence of ASD were compared between the two groups, and the influencing factors of ASD were analyzed.Results:The intraoperative blood loss, operation time, length of hospital stay and postoperative drainage in ACCF group were higher than those in ACDF group: (58.34 ± 8.61) ml vs. (46.77 ± 7.24) ml, (99.57 ± 10.72) min vs. (86.14 ± 9.64) min, (8.97 ± 1.43) d vs. (7.56 ± 1.24) d, (17.92 ± 2.95) ml vs. (14.28 ± 2.66) ml, there were statistical differences ( P<0.05). The postoperative Japanese Orthopaedic Association (JOA) scores and Neck Disability Index (NDI) scores in the two groups were improved significantly ( P<0.05), but the scores of JOA and NDI in the two groups had no significant differences ( P>0.05). The incidence of ASD in the two groups had no significant differences ( P>0.05). The Cox univariate analysis showed that age >59 years, intervertebral disc degeneration, number of fusion segments >2, osteoporosis and postoperative ASD were risk factors for ASD( P<0.05). Conclusions:The effect of microscopically ACDF is similar to that of ACCF in the treatment of cervical spondylotic myelopathy, but ACDF has the advantages of less trauma and quick recovery. The risk of postoperative ASD should be vigilant for patients with age >59 years old, intervertebral disc degeneration, number of fusion segments >2 or osteoporosis.
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OBJECTIVE@#To explore the effect of facet joint degeneration in adjacent segments on the incidence of adjacent segment disease (ASD) after lumbar fusion and fixation.@*METHODS@#A retrospective analysis was performed on 138 patients who underwent L5S1 posterior lumbar interbody fusion (PLIF) from June 2016 to June 2019. Patients were divided into a degeneration group (68 cases) and a non-degenerative group (70 cases) based on the presence or absence of L4,5 facet joint degeneration before surgery (graded using the Weishaupt standard). Age, gender, body mass index (BMI), follow-up time, and preoperative L4,5 intervertebral disc degeneration (graded using the Pfirrmann standard) were collected for both groups. Clinical outcomes were evaluated using the visual analogue scale (VAS) and Oswestry disability index (ODI) at 1 and 3 months after surgery. The incidence and time of ASD after surgery were analyzed.@*RESULTS@#There were no significant differences between the two groups in age, gender, BMI, follow-up time, or preoperative L4,5 intervertebral disc degeneration. Both groups showed significant improvement in VAS and ODI at 1 and 3 months after surgery (P<0.001), with no significant difference between the groups(P>0.05). However, there was a statistically significant difference in the incidence and timing of ASD between the groups (P<0.05). The degeneration group had 2 cases of ASD in gradeⅠdegeneration, 4 cases of ASD in gradeⅡdegeneration, and 7 cases of ASD in grade Ⅲ degeneration. There was a statistically significant difference between the number of patients with grade Ⅲ degeneration and those with gradesⅠandⅡASD (P<0.0167, Bonferroni correction).@*CONCLUSION@#Preoperative degeneration of adjacent articular processes will increase the risk of ASD after lumbar fusion fixation, whereas gradeⅢ degeneration will further increase the risk.
Subject(s)
Humans , Intervertebral Disc Degeneration/surgery , Zygapophyseal Joint/surgery , Retrospective Studies , Spinal Fusion/adverse effects , Lumbar Vertebrae/surgery , Spondylosis , Treatment OutcomeABSTRACT
Objective:To explore the feasibility and clinical efficacy of oblique lateral interbody fusion (OLIF) in the treatment of adjacent segment disease (ASDis).Methods:Retrospective analysis was conducted on the data of 31 patients with ASDis treated by OLIF in four medical centers from June 2015 to December 2018. There were 17 males and 14 females. The average age was (65.7±3.4) years (range, 59 to 75 years). 19 cases received single-segment fixed fusion, 11 cases received double-segment fixed fusion and 1 case received three-segment fixed fusion. Original fixed fusion site: 1 case of L 1, 2, 3 cases of L 3, 4, 11 cases of L 4, 5, 4 cases of L 5S 1, 6 cases of L 3-L 5, 5 cases of L 4-S 1, and 1 case of L 3-S 1. The time from the initial fixation and fusion to this admission was 82.5±45.5 months (rang, 24 to 180 months). ASDis occurred at the proximal end of the fixed fusion segment in 28 cases and at the distal end in 3 cases. The types of ASDis: degenerative disc disease in 11 cases, lumbar spinal stenosis in 15 cases, degenerative spondylolisthesis in 2 cases, and degenerative scoliosis in 3 cases. The location of ASDis: 6 cases of L 2, 3, 12 cases of L 3, 4, 6 cases of L 4, 5, 3 cases of L 1-L 3, 1 case of L 2-L 4, and 3 cases of L 1-L 4. At admission, 3 cases of lumbar internal fixation had been removed and 28 cases of internal fixation remained. Stand-alone OLIF was performed in 19 cases, OLIF combined with pedicle screw fixation in 8 cases, and OLIF combined with cortical screw fixation in 4 cases. Visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate the low back pain and lumbar function before operation and at the last follow-up, and the imaging results and complications were observed. Results:All patients were followed up. The follow-up time was 23.6±9.6 months (range, 12 to 60 months). The operation time was 73.8±25.3 mins (range, 40 to 180 min), and the intraoperative blood loss was 86.2±67.4 ml (range, 20 to 310 ml). The average blood loss in each segment was 24.8 ml. During the operation, there were 1 case of segmental vein injury, 7 cases of endplate injury, 2 cases of transient iliopsoas muscle weakness, 1 case of thigh pain and numbness, and 1 case of incomplete intestinal obstruction. There was no incision necrosis and infection. The VAS score of low back pain decreased from 5.9±1.9 before operation to 1.4±0.6 at the last follow-up, with a statistically significant difference ( t=8.47, P<0.001). The ODI index recovered from 45.2%±5.7% before operation to 13.8%±4.7% at the last follow-up, with a statistically significant difference ( t=7.92, P<0.001). The height of intervertebral space increased from 8.7±1.6 mm before operation to 11.4±1.9 mm after operation and 9.9±1.8 mm at the last follow-up. There was a statistically significant difference between postoperative and preoperative height of intervertebral space ( F=4.15, P=0.007). There was a statistically significant difference between the last follow-up and postoperative height of intervertebral space ( P=0.011). During the follow-up, there were 13 cases of fusion cage subsidence, 1 case of fusion cage displacement, and no case of internal fixation loosening or fracture. The intervertebral fusion rate was 94%(29/31) and the complication rate was 42%(13/31). Conclusion:ASDis is a common complication after lumbar fixation and fusion, and requires surgical treatment. OLIF is a reliable method to treat ASDis as it has advantages of small trauma, high fusion rate and low complication rate.
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Resumen: Introducción: Se ha realizado un estudio clínico comparativo sobre los pacientes intervenidos mediante artrodesis intersomática lateral para tratamiento de la enfermedad del segmento adyacente utilizando dispositivos intersomáticos de titanio y de PEEK. Material y métodos: Se han analizado y comparado los resultados clínicos (EVA y oswestry disability index ODI) y radiológicos (alineamiento y fusión), las complicaciones (mayores y menores) y la calidad de vida (EQ5D) de 32 pacientes intervenidos desde Septiembre de 2015 hasta Septiembre de 2018, con un seguimiento medio de 25 meses (46-18). La edad media en la cirugía fue de 66 años (39-89) y 68% de los pacientes fueron mujeres. El segmento intervenido con más frecuencia fue L3-L4 (62%) abordaje retroperitoneal derecho 86%. La EVA lumbar mejoró de 6.2 ± 2.12 a 4.1 ± 1.71 (p = 0.028). La EVA de la pierna descendió de 5.3 ± 2.26 a 1.9 ± 1.58 (p = 0.02). La escala ODI mejoró de 50.2 ± 18.9 a 33.3 ± 10.2 (p = 0.025) y la EQ5D pasó de 0.52 a 0.73 (p = 0.039) sin diferencias estadísticamente significativas entre los grupos (ODI p = 0.18, EQ5D p = 0.293). Radiológicamente aumentó la altura intervertebral, la lordosis lumbar y segmentaria, disminuyó el ángulo de Cobb y la tasa de fusión global fue de 84.3% (88% Ti/82% PEEK), sin diferencias entre los grupos. Conclusiones: La artrodesis intersomática lumbar lateral Lateral Lumbar Interbody Fusion es un método eficaz para el tratamiento de la enfermedad del segmento adyacente con resultados clínicos-radiológicos y complicaciones similares a la literatura. No se han encontrado diferencias entre los implantes de Ti y de PEEK.
Abstract: Introduction: A comparative clinical study has been conducted on patients involved using lateral intersomatic arthrodesis for the treatment of adjacent segment disease using titanium and PEEK intersomatic devices. Material and methods: Clinical (EVA and oswestry disability index ODI) and radiological (alignment and fusion), complications (major and minor) and quality of life (EQ5D) of 32 patients intervened from September 2015 to September 2018 have been analyzed and compared, with an average follow-up of 25 months (46-18). The average age in surgery was 66 years (39-89) and 68% of patients were women. Results: The most common segment involved was L3-L4 (62%) right retroperitoneal approach 86%. Lumbar EVA improved from 6.2 ± 2.12 to 4.1 ± 1.71 (p = 0.028). The LEG EVA descended from 5.3 ± 2.26 to 1.9 ± 1.58 (p = 0.02). The ODI scales improved from 50.2 ± 18.9 to 33.3 ± 10.2 (p = 0.025) and the EQ5D went from 0.52 to 0.73 (p = 0.039) with no statistically significant differences between the groups (ODI p = 0.18, EQ5D p = 0.293). Radiologically increased intervertebral height, lumbar and segmental lordosis, decreased Cobb's angle and the overall melting rate was 84.3% (88% Ti/82% PEEK), with no differences between the groups. Conclusion: Lateral lumbar interbody fusion is an effective method for treating adjacent segment disease with clinical-radiological results and literature-like complications. No differences have been found between Ti and PEEK implants.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Quality of Life , Spinal Fusion , Retrospective Studies , Treatment Outcome , Lumbar Vertebrae/surgery , Lumbar Vertebrae/diagnostic imagingABSTRACT
BACKGROUND: The Topping-off technique, which combines lumbar fusion with the dynamic internal fixation system (Coflex), can not only reduce the pressure, but also protect the adjacent segments. There is no relevant mechanical analysis performed on the rationality of the application of Topping-off technique to young patients with the need for fusion on the lumbosacral region and adjacent degenerated segments. OBJECTIVE: To establish a finite element model of Topping-off surgery on the lumbosacral junction and to analyze the biomechanical changes of the adjacent segments and the range of motion trend of the lumbar spine. METHODS: A healthy young male volunteer with no previous history of low back pain or congenital malformations was randomly selected for thin-slice CT scanning after signed the informed consent. The image information was imported into the computer and the whole lumbar spine model as the healthy group model was established by analyzing the image information through Mimics, Geomagic Studio 12.0, HyperMesh and Abaqus successively. After verifying the effectiveness of the model, the moderate degeneration model of intervertebral disc was established by changing the material properties of L4-s1 discs on the basis of the healthy model, and the fusion model and Topping-off model were respectively established on the basis of the degeneration model. After applying 400 N compressive load and 10 N-m momentum to the four groups of models, the variation trends of range of motion from L2 to L5 and the stress changes of L4/L5 intervertebral disc, nucleus pulposus and facet joints were calculated respectively. RESULTS AND CONCLUSION: (1) Compared with the degeneration model, the lumbar range of motion of Topping-off model and fusion model decreased, and the Topping-off model decreased more significantly than the fusion model. (2) The range of motion of fusion model L4-L5 increased significantly and the range of motion of L2/L3 and L3/L4 segments did not change significantly. Compared with the degeneration model, the L4-L5 range of motion of Topping-off model decreased, and range of motion of the L2/L3 and L3/L4 levels increased to some extent in the flexion and extension positions. (3) Compared with the degeneration model, the stress on the disc, nucleus pulposus and facet joint of the fusion model L4-L5 increased in four positions of flexion, extension, rotation and bending, while the fiber stress on the Topping-off model decreased significantly in all four positions. (4) These results suggest that Topping-off technology can not only reduce the stress on the upper adjacent degenerative intervertebral disc, nucleus pulposus and facet joints, but also reduce the hyperactivity of the adjacent segments and increase the range of motion of other upper segments, thereby compensating the lumbar spine mobility and delaying the degeneration of upper adjacent segments.
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BACKGROUND: The non-fusion system of lumbar interspinous process distraction device provides a new treatment option for lumbar degenerative diseases. However, at present, the clinical application and research of lumbar interspinous process distraction device are reported insufficiently in China, especially for the domestic lumbar interspinous process distraction device. OBJECTIVE: To verify the scientific nature and effectiveness of the new domestic lumbar interspinous process distraction device through finite element analysis and in vitro biomechanical experiment of goat lumbar spine. METHODS: (1) Finite element analysis of new domestic lumbar interspinous process distraction device: L2-L5 three-dimensional model of vertebral body was established based on normal adult lumbar CT data. From then on, new domestic lumbar interspinous process distraction device model, new lumbar interspinous process distraction device model of lumbar non fusion system were successively built. The mechanical conditions were given under the physiological conditions of lumbar spine. Biomechanical analysis was carried out before and after the new domestic lumbar interspinous process distraction device was implanted. (2) In vitro biomechanical analysis of new domestic lumbar interspinous process distraction device: the lumbar vertebrae (L1-L5) of 24 adult male goats were obtained, and the new domestic lumbar interspinous process distraction device was implanted between the L3-4 spinous process. Before and after the placement of the lumbar interspinous process distraction device, the lumbar motion range and the pressure of the intervertebral disc under the flexion, extension, lateral bending and rotation of the lumbar specimens were detected. RESULTS AND CONCLUSION: (1) After the new lumbar interspinous process distraction device was implanted, the motion range and the pressure of the intervertebral disc of responsible segment were reduced, while the adjacent segments' mobility and the pressure of the intervertebral disc were almost unaffected. It was theoretically verified that the new domestic lumbar interspinous process distraction device could provide the biomechanical basis for the treatment of the lumbar degenerative diseases, and contribute to the theoretical reference for the prevention of the clinical diseases. (2) In the state of extension, the motion range of L3-4 vertebral body after implanting the new lumbar interspinous process distraction device was significantly lower than that before implantation (P 0. 05). In the state of flexion, lateral bending and rotation, there was no significant difference between L2-3, L3-4 and L4-5 vertebral body after implanting the lumbar interspinous process distraction device and that before implantation (P > 0. 05). In the state of extension, the pressure of intervertebral disc after L3-4 vertebral body implantation was significantly lower than that before implantation (P 0. 05). In the state of flexion, lateral bending and rotation, there was no significant difference between L2-3, L3-4 and L4-5 vertebral body implantation and that before implantation (P > 0. 05). (3) The results showed that the scientific nature and validity of the new domestic lumbar interspinous process distraction device was verified by three-dimensional finite element analysis and in vitro animal lumbar specimens experiment, which provided a strong basis for the animal experiment, clinical experiment, clinical application and clinical production of the new domestic lumbar interspinous process distraction device.
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BACKGROUND: The clinical occurrence of lumbar degenerative diseases is often accompanied by multi-segments lesions. To slow down the degeneration of adjacent segments after lumbar fusion, lumbar hybrid surgery has become a better choice. In the past clinical observation, WavefleX system has achieved a certain effect on single segment. Its application in lumbar hybrid surgery lacks the support of biomechanical research results. OBJECTIVE: To analyze the biomechanical effects of lumbar fusion combined with WavefleX system on adjacent segments by the finite element method. METHODS: A 64-row Siemens spiral CT machine was used to scan the lumbar spine of a stationary supine volunteer with a scanning range of T11-S1. This voluntter signed the informed consent. This study was approved by the Hospital Ethics Committee. L3-5 horizontal scanning data were imported into the Mimics medical image processing software and the Geomagic studio reverse engineering software for processing. L3-5 lumbar spine solid model was constructed in the CAD software SCDM. On the basis of L3-5 lumbar model, posterior lumbar interbody fusion model and Hybrid model were constructed respectively. Assignment and load loading were conducted in three models. The finite element analysis was carried out under the conditions of forward flexion, backward extension, lateral flexion and rotation. RESULTS AND CONCLUSION: (1) Compared with posterior lumbar interbody fusion model, the stress value of L3-4 disc in Hybrid model decreased significantly in forward flexion, backward extension, lateral flexion and rotation, and the maximum value decreased about 46% in extension. (2) Compared with posterior lumbar interbody fusion model, the range of motion of L3-4 segment in Hybrid model decreased significantly, with an average decrease of about 26%, which was smaller than that of the complete model under all conditions. (3) Under each load, the stress nephogram showed that there was an obvious stress concentration on the connecting rod of WavefleX system, and the stress at the U-shaped groove concave of the elastic system on both sides was significantly increased. (4) Displacement nephogram showed the placement of WavefleX system in Hybrid model, which made its forward bending center moved back to the elastic structure. (5) The above results show that posterior lumbar interbody fusion + WavefleX semi-rigid fixation can effectively reduce the stress of the last adjacent segment of the disc and limit the excessive activity, maintain the normal movement characteristics of the lumbar spine to a certain extent.
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BACKGROUND: Decompression-fixation-fusion is the key to spinal surgery since early effective fixation to achieve intervertebral fusion can restore spinal stability in lumbar degenerative disease. OBJECTIVE: To compare biomechanical stability of fusion segment and adjacent segments of bilateral pedicle screw fixation, unilateral pedicle screw fixation and unilateral pedicle screw combined with contralateral translaminar facet screw fixation under transforaminal lumbar interbody fusion. METHODS: Eighteen fresh calf L3-5 specimens were selected. Different forms of fixation were conducted under transforaminal lumbar interbody fusion. The specimens were divided into group A (complete specimens) and group B (bilateral pedicle screws), group C (unilateral pedicle screws), and group D (unilateral pedicle screw combined with contralateral translaminar facet screw). The range of motion of adjacent segment L3-4 and fusion segment L4-5 in six directions of backward extension, forward bending, left bending, right bending, left rotation and right rotation and the stiffness of fusion segment L4-5 were tested. RESULTS AND CONCLUSION: (1) For the range of motion of fusion segment L4-5, the stability was highest in the group B in six directions, followed by group D, which showed similar results in rotation in the group B (P > 0.05). The stability of right curvature and left rotation in group C was insufficient, and there was no significant difference in range of motion between group A and group C (P > 0.05). The range of motion in group A was largest and the stability was worst in the six motion directions. (2) For the stiffness value of fusion segment L4-5, the stiffness value of group B was largest in six directions, which was significantly different from other groups (P 0.05). There was no significant difference between group C and group A in the range of motion of six directions (P > 0.05). (4) The results showed that the motion ramge of unilateral pedicle screw fixation in the right and left rotation directions was large in the early stage, which was close to that of the complete specimen group. There is a shortage of stability, so we need to use it carefully and grasp the indications strictly. Unilateral pedicle screw fixation combined with contralateral translaminar facet screw fixation improves the disadvantages of asymmetric fixation of unilateral pedicle screw, increases the stability of rotation and lateral bending, and avoids the influence of bilateral pedicle screw fixation on adjacent segments, thus becoming an effective clinical surgical treatment.
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OBJECTIVE: The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions.METHODS: The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On pre-op magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb’s angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed.RESULTS: Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846).CONCLUSION: In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.
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Humans , Follow-Up Studies , Incidence , Intervertebral Disc Degeneration , Magnetic Resonance Imaging , Medical Records , Pliability , Range of Motion, Articular , Retrospective Studies , Risk Factors , Spinal Fusion , SpineABSTRACT
STUDY DESIGN: Retrospective study.OBJECTIVES: To compare the degeneration of sacroiliac joint (SIJ) following lumbar or lumbosacral fusion.SUMMARY OF LITERATURE REVIEW: The SIJ is adjacent to lumbosacral junction and its degeneration can be the potential cause of pain. However, the study addressing SIJ degeneration following lumbar or lumbosacral fusion is very limited.MATERIALS AND METHODS: From June 2002 to June 2012, 98 patients who underwent posterior decompression and posterolateral fusion were included in this study. The study group was divided into 2 groups according to the range of fusion. Group A had fusion to L5 and included 34 patients. Group B had fusion to S1 and included 64 patients. We evaluated the five years postoperative radiologic and clinical outcomes retrospectively.RESULTS: There was no statistically significant difference of bilateral preoperative subchondral sclerosis and osteophytes of the SIJ between group A and group B. However, group B revealed statistically significant subchondral sclerosis and osteophyte formation of the SIJ than group A on every radiographs after postoperative 1 year. In group B, the number of fusion segments and age were statistically positively correlated with the degeneration of the SIJ.CONCLUSIONS: Degeneration of the SIJ revealed more rapid and more severe progression in lumbosacral fusion group than in lumbar fusion group. The number of fusion segments and age were positively correlated with the degeneration of the SIJ in lumbosacral fusion group. Therefore, these facts should be taken into account when performing spinal fusion.
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Humans , Decompression , Osteophyte , Retrospective Studies , Sacroiliac Joint , Sclerosis , Spinal FusionABSTRACT
OBJECTIVE: The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. METHODS: The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On pre-op magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb’s angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. RESULTS: Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). CONCLUSION: In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.
Subject(s)
Humans , Follow-Up Studies , Incidence , Intervertebral Disc Degeneration , Magnetic Resonance Imaging , Medical Records , Pliability , Range of Motion, Articular , Retrospective Studies , Risk Factors , Spinal Fusion , SpineABSTRACT
Objective To analyze the correlation between adjacent segment disease (ASDis) after lumbar fusion and spinopelvic sagittal parameters, and to explore the risk factors. Methods From Jan. 2013 to Oct. 2017, the patients undergoing revision surgery for ASDis after lumbar fusion in Changhai Hospital of Naval Medical University (Second Military Medical University) were enrolled as ASDis group, and the patients who did not have ASDis after lumbar fusion during the same follow-up period were taken as controls. The clinical data of the patients in the two groups were retrospectively analyzed. The differences of the general data (age, gender, body mass index [BMI], follow-up time and the etiology of the first operation) and the spinopelvic sagittal parameters (thoracic kyphosis [TK], sagittal vertical axis [SVA], lumbar lordosis [LL], segmental lumbar lordosis [sLL], pelvic incidence [PI], pelvic tilt [PT] and sacral slope [SS]) were compared between the two groups. Results There were 25 patients in the ASDis group and 50 patients in the control group. There were no significant differences in the age, gender, BMI, follow-up time or the etiology of the first operation between the two groups (all P>0.05). Compared with the control group, the LL, sLL and SS were significantly lower in the ASDis group (36.00°±5.44°vs 43.88°±10.62°, 17.80°±5.79°vs 27.62°±6.74°, 27.50°±5.30°vs 31.06°±7.48° all P0.05). Meantime, the proportion of patients with SVA>50 mm, the difference of PT and LL (PT-LL)=10°, and the ratio of sLL to LL (RL)<60% were significantly higher in the ASDis group than those in the control group (18/25 vs 21/50, 16/25 vs 11/50, 21/25 vs 17/50; all P<0.05). Conclusion The sagittal imbalance after lumbar fusion is closely associated with ASDis, and compensatory kyphosis of adjacent lumbar segments due to surgical segmental lordosis may be one of the causes of ASDis after lumbar fusion.
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Objective: To compare the long-term effectiveness of wheather posterior ligamentous complex (PLC) preserved between posterior fenestration decompression interbody fusion and posterior total laminectomy interbody fusion. Methods: The clinical data of 89 patients who suffered from single segmental degenerative diseases of lower lumbar spine and followed up more than 10 years after receiving lumbar spinal fusion between January 2000 and January 2005 were retrospectively analysed. The patients were divided into two groups according to the different surgical methods, the 33 patients in group A were treated with posterior lumbar fenestration decompression, interbody fusion, and internal fixation, while 56 patients in group B were treated with posterior total laminectomy resection decompression, interbody fusion, and internal fixation. There was no significant difference in gender, age, body mass index, type of lesion, disease duration, lesion segment, and preoperative Japanese Orthopedic Association (JOA) score, visual analogue scale (VAS) score, and Cobb angle of lumbar lordosis between the two groups ( P>0.05). The effectiveness was evaluated by JOA score, and the improvement of pain was evaluated by VAS score. The incidence of adjacent segment degeneration (ASD) at last follow-up was recorded. Results: Both groups were followed up 10-17 years (mean, 12.6 years). There were 3 cases (9.1%) in group A and 5 cases (8.9%) in group B complicated with cerebrospinal fluid leakage, showing no significant difference ( χ2=0.001, P=0.979). There was no complication such as infection, nerve root injury, internal plant loosening or transposition in both groups. Intervertebral fusion was satisfactory in both groups. The fusion time in groups A and B was (3.4±1.2) months and (3.7±1.6) months respectively, and there was no significant difference between the two groups ( t=0.420, P=0.676). At last follow-up, the JOA score and VAS score of the two groups were significantly improved when compared with preoperative ones ( P<0.05); there was no significant difference in Cobb angle of lumbar lordosis before and after operation in group A ( t=0.293, P=0.772), but the Cobb angle of lumbar lordosis in group B was significantly lost at last follow-up ( t=14.920, P=0.000). At last follow-up, the VAS score and Cobb angle of lumbar lordosis in group A were significantly superior to those in group B ( P<0.05); there was no significant difference in JOA score between the two groups ( t=0.217, P=0.828). There were 3 cases (9.1%) in group A and 21 cases (37.5%) in group B complicated with ASD, showing significant difference between the two groups ( χ2=8.509, P=0.004). Conclusion: Long-term effectiveness of both groups was satisfactory, but in terms of maintaining lumbar lordosis and reducing the incidence of ASD, the lumbar fusion retaining PLC is superior to total laminectomy and lumbar fusion removing PLC.
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Objective: To analyze the prospective effect of pre-existing spinal stenosis of adjacent segment on the short-term effectiveness after lumbar fusion surgery. Methods: A prospective comparative study was conducted to divide 183 patients with L 4-S 1 lumbar spinal stenosis who met the selection criteria between July 2015 and December 2017 into two groups according to the status of adjacent segment degeneration (ASD) judged by preoperative disc degeneration and spinal stenosis. There were 98 patients in group A (no degeneration of adjacent segments before operation) and 85 patients in group B (adjacent segments degenerated before operation). There was no significant difference in gender, American Society of Anesthesiologists (ASA) grade, body mass index (BMI), combined spondylolisthesis, and preoperative visual analogue scale (VAS) score of low back pain and leg pain, Japanese Orthopaedic Association (JOA) score, and Oswestry disability index (ODI) score between the two groups ( P>0.05); the age of group A was significantly younger than that of group B ( t=-3.560, P=0.000). The operation time, intraoperative blood loss, hospitalization stay, and perioperative complications were recorded and compared. The VAS score of low back pain and leg pain, JOA score, and ODI score at last follow-up were used to evaluate the effectiveness. The incidence of ASD after operation was compared between the two groups, and logistic regression was used to analyze the independent risk factors affecting the occurrence of ASD after operation. Results: There was no significant difference in operation time, intraoperative blood loss, and hospitalization stay between the two groups ( P>0.05). The incidence of perioperative complications in groups A and B was 13.3% and 20.0%, respectively, with no significant difference ( χ2=1.506, P=0.220). Two groups of patients were followed up, the follow-up time of groups A and B was (24.9±8.8) months and (24.8±7.8) months, respectively, there was no significant difference ( t=0.050, P=0.960). At last follow-up, no adjacent segment disease was found in either group. There was no significant difference in Pfirrmann grade between the two groups at last follow-up ( P>0.05), and there was significant difference in Pfirrmann grade between the two groups before operation and at last follow-up ( P<0.001). At last follow-up, 21 cases (21.4%) in group A and 53 cases (62.4%) in group B had ASD, with significant difference ( χ2=31.652, P=0.000). The main cause of ASD was the severity of adjacent spinal canal stenosis. The clinical scores of the two groups at last follow-up were significantly improved when compared with those before operation ( P<0.05). The JOA score of group A was significantly higher than that of group B at last follow-up ( P<0.05). In group B, the VAS score of low back pain and ODI score in patients with ASD after operation at last follow-up were significantly higher than those in patients without ASD ( P<0.05). logistic regression analysis showed that preoperative pre-existing degeneration and BMI were independent risk factors for ASD after operation ( P<0.05). Conclusion: Pre-existing mild spinal stenosis in adjacent segment can significantly affect the effectiveness, and can significantly increase the risk of ASD early after operation. The main pathological type of ASD was the severity of adjacent segment spinal stenosis. For preoperative assessment of pre-existing degeneration, we should evaluate the overall degeneration of the adjacent segment of the spinal canal, rather than simply evaluating the degeneration of the adjacent disc and facet joints.
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Objective To compare the effects of preserving the posterior ligament complex (PLC) with torque loading and displacement loading on the biomechanical properties of the adjacent segments after lumbar decompression and fusion. Methods Six fresh male cadaver lumbar specimens of T12-S2 were tested in the sequence of intact, L4-5 laminotomy (preserving the PLC) with fixation and L4-5 laminectomy (destructing the PLC) with fixation, by applying both displacement loading and torque loading, respectively. Ranges-of-motions (ROMs) of the adjacent segments were measured under a noncontact photographic recording system. Results In displacement-loading mode, the flexion ROM in laminectomy group was significantly higher than that in laminotomy group, and no obvious ROM differences were found in the laminectomy and laminotomy groups under extension, lateral bending, and rotation movement. Conclusions Torque loading and displacement loading have different biomechanical effects on the adjacent segments after lumbar decompression and fusion. Compared with the laminotomy method, in which the PLC is preserved, the laminectomy method in which PLC structures are damaged can obviously lead to an increment of flexion ROMs at the adjacent segments, and also increase the ROMs of the adjacent segments under extension, lateral bending, and rotation movements, which might increase the risk of further instability of the fused adjacent segments.
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Objective To study the biomechanical influence of posterior laminectomy with varying extent on adjacent segment after lumbar interbody fusion. Methods Three finite element models of lumbar posterior fusion were developed based on the validated intact lumbar model. These models were: posterior fusion with bi-lateral incision of facet joint (Bi-TLIF），inferior partly incision of laminar (PLIF)，total laminectomy (LAM-PLIF). The range of motion (ROM), intradiscal pressure (IDP), facet joint contact force (FJF) of adjacent segment of fusion models under various loading were compared with the intact model. The follower load of 400 N under 7.5 N·m torque was exerted on superior endplate of L1 segment. The 6-DOF (degree of freedom) of sacroiliac joint surface was constrained during loading. ResultsDuring flexion, obvious biomechanical changes of superior adjacent segment (L3-4) were found in Bi-TLIF, PLIF, LAM-PLIF surgery groups. Compared with the intact model, the ROM in Bi-TLIF, PLIF, LAM-PLIF group increased by 1.0%, 9.3%, 24.5%, respectively, while IDP in the above fusion groups increased by 1.4%, 4.3%, 10.0%，respectively. These changes were not obvious in other postures. For FJF, the Bi-TLIF and PLIF group showed obvious increasing effect on L3-4 segment, while almost had no effect on L5-S1 segment. Conclusions Laminectomy increased ROM, IDP and FJF of adjacent segment (especially superior adjacent segment) after posterior lumbar fusion, which might increase the risk of adjacent segment degeneration. This biomechanical effect was more obvious with the increase in incision range of laminar. Therefore, preserving more posterior complex during decompression has a positive effect on preventing adjacent segment degeneration (ASD) following lumbar fusion surgeries.
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PURPOSE: We prospectively assessed the early radiographic and clinical outcomes (minimum follow-up of 2 years) of robot-assisted pedicle screw fixation (Robot-PSF) and conventional freehand pedicle screw fixation (Conv-PSF). MATERIALS AND METHODS: Patients were randomly assigned to Robot-PSF (37 patients) or Conv-PSF (41 patients) for posterior interbody fusion surgery. The Robot-PSF group underwent minimally invasive pedicle screw fixation using a pre-planned robot-guided screw trajectory. The Conv-PSF underwent screw fixation using the freehand technique. Radiographic adjacent segment degeneration (ASD) was measured on plain radiographs, and clinical outcomes were measured using visual analogue scale (VAS) and Oswestry disability index (ODI) scores regularly after surgery. RESULTS: The two groups had similar values for radiographic ASD, including University California at Los Angeles grade, vertebral translation, angular motion, and loss of disc height (p=0.320). At final follow-up, both groups had experienced significant improvements in back VAS, leg VAS, and ODI scores after surgery (p < 0.001), although inter-group differences were not significant for back VAS (p=0.876), leg VAS (p=0.429), and ODI scores (p=0.952). In the Conv-PSF group, revision surgery was required for two of the 25 patients (8%), compared to no patients in the Robot-PSF group. CONCLUSION: There were no significant differences in radiographic ASD and clinical outcomes between Robot-PSF and Conv-PSF. Thus, the advantages of robot-assisted surgery (accurate pedicle screw insertion and minimal facet joint violation) do not appear to be clinically significant.
Subject(s)
Humans , California , Follow-Up Studies , Leg , Pedicle Screws , Prospective Studies , Zygapophyseal JointABSTRACT
<p><b>Background</b>Many clinical studies over the past decade have indicated positive outcomes for patients treated with Dynesys dynamic stabilization for lumbar degenerative disease. However, long-term outcomes of Dynesys for lumbar spinal stenosis are rarely reported. The aim of this study was to analyze the long-term clinical and radiologic outcomes for patients with lumbar spinal stenosis treated with Dynesys stabilization.</p><p><b>Methods</b>Thirty-eight patients with lumbar spinal stenosis were treated with Dynesys stabilization from July 2008 to March 2010. The minimal duration of follow-up was 72 months. The patients were divided into stenosis and spondylolisthesis groups according to degenerative spondylolisthesis. Clinical outcomes were evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS). Radiographic evaluations included range of motion (ROM) and the disc heights of stabilized segments and the upper adjacent segments. We also evaluated the occurrence of radiographic and symptomatic adjacent segment degeneration (ASD).</p><p><b>Results</b>There were 23 patients in stenosis group and 15 patients in spondylolisthesis group. The ODI scores were significantly improved at the final follow-up evaluation, as compared to the baseline values (16.1 ± 5.7 vs. 57. 2 ± 14.2, t = 61.41, P < 0.01). The VAS scores for back and leg pain were significantly improved from 4.82 ± 0.89 and 4.04 ± 0.82 preoperatively to 0.93 ± 0.61 and 0.54 ± 0.51 postoperatively (t = 6.59, P < 0.01, and t = 5.91, P < 0.01, respectively). There were no differences between the two groups with respect to VAS and ODI scores. The ROM of stabilized segments decreased significantly from 7.8° ± 2.4° to 4.5° ± 1.5° (t = 7.18, P < 0.05), while the upper adjacent segments increased significantly from 8.3° ± 2.4° to 10.4° ± 2.4° (t = 2.87, P = 0.01). The change in disc height of stabilized segments was not significant (11.9 ± 2.1 preoperatively vs. 12.5 ± 1.5 postoperatively, t = 1.43, P = 0.15), whereas the decrease in disc height of the upper adjacent segments was significant (12.5 ± 2.0 preoperatively vs. 11.0 ± 1.7 postoperatively, t = 2.94, P = 0.01). The occurrence of radiographic and symptomatic ASD was 16% (6/38) and 3% (1/38), respectively.</p><p><b>Conclusions</b>Decompression and Dynesys stabilization for lumbar stenosis with or without spondylolisthesis showed good long-term clinical and radiographic results. Lumbar stenosis with or without Grade I spondylolisthesis, particularly in patients <60 years of age with mild-to-moderate lumbar disc degeneration, would be one of the main indications for the Dynesys system.</p>
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<p><b>OBJECTIVE</b>To compare the clinical effect between the lamina osteotomy and former vertebral plates regraft method and total laminectomy and interbody fusion method in treating single-segment lumbar degenerative disease.</p><p><b>METHODS</b>The clinical data of 167 patients with single-segment lumbar degenerative disease underwent surgical treatment from January 2010 to December 2014 were retrospectively analyzed. There were 92 males and 75 females, aged from 45 to 75 years old with an average of (59.6±12.4) years. The patients were divided into lamina osteotomy and former vertebral plates regraft group(82 cases) and total laminectomy and interbody fusion group(85 cases) according to the different surgical methods used. The general conditions and clinical effects were compared between two groups. General conditions included the operation time, intraoperative blood loss, postoperative drainage, hospitalization time and the clinical effects included the visual analogue scale (VAS), Japanese Orthopaedic Association(JOA), Oswestry Dability Index(ODI), MacNab results, epidural fibrosis (EF), the incidence of adjacent segment degeneration (ASD).</p><p><b>RESULTS</b>All the patients were followed for 18 to 36 months with an average of (24.8±5.7) months, furthermore, there was no significant difference in the follow-up time between two groups. There was no significant difference in general conditions such as operation time, intraoperative blood loss, postoperative drainage, or hospitalization time between two groups. At final follow-up, the VAS, ODI, JOA, of all patients were significantly improved (<0.05);and the three factors above in the lamina osteotomy and former vertebral plates regraft group respectively were(2.0±1.1) points, (24.0±1.8) %, (19.8±8.2) point, while the results of total laminectomy and interbody fusion group were(2.5±1.6) points, (23.3±2.0)%, and(22.5±8.5) point;there was statistical difference between two groups(<0.05). According to the standard of MacNab, 59 cases obtained excellent results, 20 good, 3 fair results in the lamina osteotomy and former vertebral plates regraft group;while 47 cases got excellent results, 26 good, and 12 fair results in the total laminectomy and interbody fusion group;there was significant difference between two groups(<0.05). Sixteen patients(19.51%) with EF and 20 patients(24.39%) with ASD were found in lamina osteotomy and former vertebral plates regraft group;and 30 patients(35.29%) with EF and 37 patients(43.53%) with ASD were found in total laminectomy and interbody fusion group; there was significant difference between two groups(<0.05).</p><p><b>CONCLUSIONS</b>Both two methods can achieve the ideal effects for the treatment of single-segment lumbar degenerative disease, but the lamina osteotomy and former vertebral plates regraft method can reserve the integrity of posterior ligamentous complex, reducing the incidence of EF and ASD, and is a better surgical method.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Bone Transplantation , Laminectomy , Lumbar Vertebrae , Pathology , General Surgery , Lumbosacral Region , Osteotomy , Retrospective Studies , Spinal Fusion , Treatment OutcomeABSTRACT
STUDY DESIGN: Retrospective study. PURPOSE: To investigate the relationship between preoperative total spinal sagittal alignment and the early onset of adjacent segment degeneration (ASD) after single-level posterior lumbar interbody fusion (PLIF) in patients with normal sagittal spinal alignment. OVERVIEW OF LITERATURE: Postoperative early-onset ASD is one of the complications after L4–L5 PLIF, a common surgical procedure for lumbar degenerative disease in patents without severe sagittal imbalance. A better understanding of the preoperative characteristics of total spinal sagittal alignment associated with early-onset ASD could help prevent the condition. METHODS: The study included 70 consecutive patients diagnosed with lumbar degenerative disease who underwent single-level L4–L5 PLIF between 2011 and 2015. They were divided into two groups based on the radiographic progression of L3–L4 degeneration after 1-year follow-up: the ASD and the non-ASD (NASD) group. The following radiographic parameters were preoperatively and postoperatively measured: sagittal vertebral axis (SVA), thoracic kyphosis (TK), lumbar lordosis, pelvic tilt, and pelvic incidence (PI). RESULTS: Eight of the 70 patients (11%) experienced ASD after PLIF (three males and five females; age, 64.4±7.7 years). The NASD group comprised 20 males and 42 females (age, 67.7±9.3 years). Six patients of the ASD group showed decreased L3–L4 disc height, one had L3–L4 local kyphosis, and one showed both changes. Preoperative SVA, PI, and TK were significantly smaller in the ASD group than in the NASD group (p <0.05). CONCLUSIONS: A preoperative small SVA and TK with small PI were the characteristic alignments for the risk of early-onset ASD in patients without preoperative severe sagittal spinal imbalance undergoing L4–L5 single-level PLIF.