Zu-De Liu

Shanghai Jiao Tong University, Shanghai, Shanghai Shi, China

Are you Zu-De Liu?

Claim your profile

Publications (19)25.91 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background The management for degenerative lumbar spondylolisthesis with spinal stenosis remains controversial. Reduction of lumbar spondylolisthesis has been performed via numerous techniques. Most of them need extra reduction assembly. Methods In this retrospective analysis, 27 patients of degenerative lumbar spondylolisthesis with spinal stenosis underwent reduction using polyaxial screw and rod constructs and posterolateral fusion. The average age at the time of surgery was 53 ± 3.23 years. The outcome measures consisted of a radiographic assessment of deformity and fusion rate and a clinical assessment of perioperative improvement in low back pain and function. Preoperative and postoperative radiographic evaluation included the percent slip, slip angle, and the lumbar lordosis between L1 and the sacrum measured using the Cobb method. Before surgery and at the final follow-up, the Oswestry Disability Index (ODI) and the visual pain analog scale (VPAS) between 0 (no pain) and 10 (maximal pain) were quantified. Results The average follow-up period more than 5 years was available. The mean operative time was 90.19 ± 14.51 min, and the mean blood loss during surgery was 152.59 ± 45.71 ml. The mean length of incision was 4.83 ± 0.63 cm. The average percent slippage and the mean slip angle were, respectively, 19.8 ± 4.49% and 9.69 ± 3.79° before surgery, 5.09 ± 3.40% and 6.39 ± 3.16° after surgery, and 5.67 ± 3.92% and 7.21 ± 3.05° at the last follow-up. The average lumbar lordosis was 36.88 ± 2.64° before surgery, 41.96 ± 1.64° after surgery, and 40.27 ± 1.19° at the final follow-up. No neurologic deficit occurred. Solid fusion was achieved for all cases. Compared with the outcome preoperation, the data improved from 6.56 ± 1.40 to 2.48 ± 1.16 for VPAS pain scores and from 32.22 ± 3.57 to 10.93 ± 4.93 for the ODI at the final follow-up. Conclusions Lever slip reduction maneuver techniques using polyaxial screw and rod fixation system was simple and practicable. The treatment outcomes showed satisfactory radiographic characteristics and clinical results. The length of the incision was relatively small with a low intraoperative blood loss and short operation time.
    Journal of Orthopaedic Surgery and Research 12/2015; 10(1). DOI:10.1186/s13018-015-0168-x · 1.58 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We aimed to evaluate whether FGF-21 concentration in serum and synovial fluid (SF) is associated with radiographic bone loss of knee osteoarthritis (OA). A total of 186 OA patients and 108 controls were recruited. The radiographic bone loss of knee OA was assessed by the Ahlbäck grading scale. FGF-21 concentration in serum and SF was measured by enzyme-linked immunosorbent assay (ELISA). We demonstrated that OA patients had significantly higher serum FGF-21 concentration compared with controls (204.30 [range 158.25-279.16] ng/L vs. 130.72 [range 94.93-218.03] ng/L, p < 0.01). FGF-21 concentration in serum was well correlated with that in paired SF samples (r = 0.668, p < 0.001). In OA patients, those with a higher Ahlbäck grade had significantly higher serum and SF FGF-21 concentration (p < 0.001 for both). FGF-21 concentration in serum and SF was significantly and independently associated with the Ahlbäck grade (r = 0.403, p < 0.001 and r = 0.410, p < 0.001; respectively). These findings indicated that FGF-21 might be a potential biomarker for predicting bone loss of OA. Therapeutic interventions by blocking FGF-21 signaling pathways to delay the degenerative process of OA warrants further investigations.
    Scandinavian Journal of Clinical and Laboratory Investigation 12/2014; DOI:10.3109/00365513.2014.992942 · 2.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the clinical use of kinetic magnetic resonance imaging (kMRI) in spinal degenerative diseases. A systematic search of PubMed, EMBASE and ISI databases for articles that had been published between January 1978 and February 2013 concerning patients who had undergone kMRI for spinal problems was performed. All selected patients had undergone kMRI in neutral, flexion, and extension weight-bearing positions. Evaluation of cervical and lumbar degeneration by kMRI was analyzed. kMRI showed significant reduction of mobility in cervical segments of patients with severe disc degeneration; in addition, it was more severely reduced in patients with severe cord compression than in those without it. In the cervical spine, it was found that although disc height, translational motion, and angular variation were significantly affected at the level of disc herniation, no significant changes were apparent in adjacent segments. kMRI also showed that lumbar degeneration is closely associated with disc degeneration, facet joint osteoarthritis and the pathological characteristics of the interspinous ligaments, ligamentum flavum and paraspinal muscles. Eleven articles (4162 patients) fulfilled the inclusion criteria and were reviewed. It was found that kMRI is more specific and sensitive than conventional MRI regarding relating patients' symptoms to objective findings on imaging that demonstrate pathology and biomechanics. In the kinetic position, kMRI improves detection of disc herniation by 5.78%-19.46% and thus provides a new means of studying the biomechanical mechanism(s) in degenerative spines. Kinetic MRI is effective for diagnosing, evaluating, and managing degenerative disease within the spine; however, it still has some limitations. © 2014 Chinese Orthopaedic Association and Wiley Publishing Asia Pty Ltd.
    Orthopaedic Surgery 11/2014; 6(4):294-9. DOI:10.1111/os.12137
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives: Sexual dimorphism does occur in intervertebral disc (IVD) degeneration. The involvement of estrogen on IVD health has been well reported in recent years. The estrogen receptors (ER) are the main mediators of estrogen action. ER might play specific roles in the sexual variations of the IVD degeneration. Methods: Thirty-six elderly patients with lumbar disc degeneration were selected and graded using Pfirrmann's system based on MRI images. Differences of ER alpha and ER beta immunoreactivity staining in nucleus pulposus of each sex and degeneration degree were recorded and compared. Results: Both cytoplasmic and nuclear staining of ER alpha and ER beta immunoreactivity were observed in the nucleus pulposus cells. ER alpha and ER beta expression significantly decreased along with the aggravation of IVD degeneration both in males and females. Expression of ER alpha and ER beta protein in nucleus pulposus of males was significantly higher than that of females. Conclusions: Gender-specific expression of ER might play a part in sexual dimorphism of IVD degeneration. Gender and degeneration condition differences should be taken into account when the effects of estrogen on IVD metabolism are studied further.
    Joint, bone, spine: revue du rhumatisme 05/2014; 81(3). DOI:10.1016/j.jbspin.2013.09.002 · 3.22 Impact Factor
  • The spine journal: official journal of the North American Spine Society 04/2014; 14(9). DOI:10.1016/j.spinee.2014.04.007 · 2.80 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Rheumatoid arthritis (RA) and osteoarthritis (OA) are two major types of joint diseases that share multiple common symptoms. However, their pathological mechanism remains largely unknown. The aim of our study is to identify RA and OA related-genes and gain an insight into the underlying genetic basis of these diseases. We collected 11 whole genome-wide expression profiling datasets from RA and OA cohorts and performed a meta-analysis to comprehensively investigate their expression signatures. This method can avoid some pitfalls of single dataset analyses. We found that several biological pathways (i.e., the immunity, inflammation and apoptosis related pathways) are commonly involved in the development of both RA and OA. Whereas several other pathways (i.e., vasopressin-related pathway, regulation of autophagy, endocytosis, calcium transport and endoplasmic reticulum stress related pathways) present significant difference between RA and OA. This study provides novel insights into the molecular mechanisms underlying this disease, thereby aiding the diagnosis and treatment of the disease.
    PLoS ONE 02/2014; 9(2):e85784. DOI:10.1371/journal.pone.0085784 · 3.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Objectives Sexual dimorphism does occur in intervertebral disc (IVD) degeneration. The involvement of estrogen on IVD health has been well reported in recent years. The estrogen receptors (ER) are the main mediators of estrogen action. ER might play specific roles in the sexual variations of the IVD degeneration. Methods Thirty-six elderly patients with lumbar disc degeneration were selected and graded using Pfirrmann's system based on MRI images. Differences of ERα and ERβ immunoreactivity staining in nucleus pulposus of each sex and degeneration degree were recorded and compared. Results Both cytoplasmic and nuclear staining of ERα and ERβ immunoreactivity were observed in the nucleus pulposus cells. ERα and ERβ expression significantly decreased along with the aggravation of IVD degeneration both in males and females. Expression of ERα and ERβ protein in nucleus pulposus of males was significantly higher than that of females. Conclusions Gender-specific expression of ER might play a part in sexual dimorphism of IVD degeneration. Gender and degeneration condition differences should be taken into account when the effects of estrogen on IVD metabolism are studied further.
  • Orthopaedic Surgery 11/2013; 5(4):302-304. DOI:10.1111/os.12065
  • [Show abstract] [Hide abstract]
    ABSTRACT: Solid organ transplant recipients are at increased risk for Aspergillus infections. However, the cases of Aspergillus spondylodiscitis are rare and mostly resulted from the hematogenous spread of invasive pulmonary Aspergillosis. Here, we report a case of primary spondylodiscitis in a liver transplant recipient. Six months after transplantation, a chronic and progressive lumbar back pain was presented. The patient had no fever and the white blood cell count was normal. High plasma (1→3)-beta-d-glucan (BDG) level was detected at the time of back pain. The pathogen was Aspergillus flavus. Clinical and radiological healing was achieved through posterior only debridement and voriconazole therapy.
    Chinese medical journal 08/2012; 125(15):2772-4. · 1.02 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To study the effective recovery of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. End-to-end anastomosis was performed between the left L(1) and L(3) ventral roots using autogenous nerve graft, and the right L(1) and L(3) roots were left intact. In control animals, the left L(3) ventral root was cut and shortened, and anastomosis was not performed. Six months postoperatively, the movement of low extremities was detected by electrophysiological examination, hindlimb locomotion and basso, beattie and bresnahan (BBB) scoring at one, three, seven, 14, 21 and 28 days after SCI. Fluorescence retrograde tracing with TRUE BLUE (TB) and HE staining were performed to observe the nerve regeneration. Six months after surgery, the anastomotic nerve was smooth and not atrophic. The amplitudes of action potential were 7.63 ± 1.86 mV and 6.0 ± 1.92 mV respectively before and after the spinal cord hemisection. The contraction of left quadriceps femoris was induced by a single stimulation of the anastomotic nerve. The locomotion of left hindlimb was partially restored after spinal cord hemisection while creeping and climbing. In addition, there was significant difference in the BBB score at one, three and seven days after SCI. TB retrograde tracing and neurophysiologic observation indicated efficient reinnervation of the quadriceps femoris. The cross-anastomosis between spinal ventral root can partially reconstruct the function of quadriceps femoris following SCI and may have clinical implication for the treatment of human SCI.
    Acta cirurgica brasileira / Sociedade Brasileira para Desenvolvimento Pesquisa em Cirurgia 05/2012; 27(5):330-7. DOI:10.1590/S0102-86502012000500009 · 0.48 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study measured high-mobility group box 1 (HMGB-1) levels in serum and synovial fluid (SF) in patients with primary knee osteoarthritis (OA) and correlated these levels with radiographic disease severity. Seventy-eight OA patients and 30 controls were enrolled in this study. All OA patients were scored according to the Kellgren-Lawrence (KL) grading system. HMGB-1 levels were measured by enzyme-linked immunosorbent assay (ELISA). SF HMGB-1 levels were significantly higher in knee OA patients, compared with controls (P < 0.01). Moreover, SF HMGB-1 levels were positively associated with KL scores (P < 0.01). Multinomial logistic regression demonstrated that the SF HMGB-1 level was an independent factor for radiographic severity of OA (P=0.002); however, serum HMGB-1 levels did not differ significantly between OA patients and controls and did not correlate with KL scores (P > 0.05). These results demonstrate that HMGB-1 levels in SF of knee OA patients are independently associated with radiographic disease severity.
    Clinical and investigative medicine. Medecine clinique et experimentale 01/2011; 34(5):E298. · 1.15 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Numerical techniques were used to study the vibration response of idiopathic scoliosis patients with single thoracic curve. To analyze the dynamic characteristics of the idiopathic scoliotic spine under the whole-body vibration condition. The influence of the upper body mass was also studied. The relationship between the whole-body vibration and the spinal disorders has been investigated using finite element method. However, the dynamic response features of the scoliotic spine to the vibration were poorly understood. The resonant frequencies of the scoliotic spine and the effects of the body weight were studied using a finite element model described previously. Modal and harmonic analysis was conducted. The amplitudes of 6 fundamental vertebral movements around the long, coronal and sagittal axis were quantified in the frequency range of 1 to 35 Hz. The vibration-induced rotation amplitudes of the apex of the thoracic deformity were higher than that of the lumbar segments. The apical vertebrae had the greatest rotation amplitudes at 2 and 8 Hz, and the largest lateral translation amplitudes at 16 Hz. Vibration could cause large lateral flexion amplitudes in the apex of the thoracic deformity. The apical vertebrae had the largest side flexion amplitudes at 6 Hz. Increasing upper body mass could not change resonant frequency of vibration-induced lateral translation and rotation around the long axis of the apical vertebrae. The scoliotic spine is more sensitive to vibration than the normal spine. For a patient with single thoracic curve, long-term whole-body vibration may do more harm to the thoracic deformity than to the lower lumbar segments. Axial cyclic loads applied to an already deformed spine may cause further rotational and scoliotic deformity. The patients with idiopathic scoliosis are more likely to suffer from vibration-induced spinal disorders than those by normal persons.
    Spine 11/2010; 36(7):521-8. DOI:10.1097/BRS.0b013e3181d55fb0 · 2.45 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Surgical treatment of scoliosis associated with Marfan syndrome poses a challenge to spine surgeons. This retrospective study was undertaken to determine whether posterior-only surgery with instrumented fixation and fusion addresses the correction of scoliosis and maintains curve correction. Twelve consecutive patients with Marfan syndrome were treated between 2002 and 2007 for scoliosis by posterior segmental instrumentation using pedicle screws or hybrid thoracic-hook and lumbar-screw constructs. Their preoperative Cobb angle averaged 66 ± 10° (range: 55-90°). The average operation time was 252 ± 36 min (range: 200-300 min) and the average blood loss was 690 ± 117 ml (range: 550-920 ml). No significant complications were found. All the patients were followed for a minimum of 2 years (range: 2.4-6.8 years). The average Cobb angle was corrected to 23 ± 8° (range: 13-35°) immediately after surgery and 28 ± 9° (range: 14-43°) with a correction rate of 58 ± 13% at final follow-up. The results indicate that posterior-only surgery with instrumented fixation and fusion is effective and safe for the treatment of scoliosis in selected patients with Marfan syndrome.
    Journal of pediatric orthopaedics. Part B / European Paediatric Orthopaedic Society, Pediatric Orthopaedic Society of North America 11/2010; 20(2):63-6. DOI:10.1097/BPB.0b013e328341bcc9 · 0.66 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the effect of the rib cage on the vertebral axial rotation of adolescent idiopathic scoliosis under axial load condition. Three dimensional finite element model of adolescent idiopathic scoliosis included and excluded thoracic cage was built based on the data of computer tomography. The model was imported into the preprocessor of the ANSYS 8.0 software for assigning boundary and loading conditions. Then the axial loading condition was simulated after entering the solution modular. The magnitude and direction of each vertebral axial rotation of the scoliotic spine were read and analyzed in the postprocessor of the ANSYS software. The rib cage had a significant influence on the axial rotation of the vertebra above the structural curve and had no influence on the axial rotation of the lumbar and sacral vertebra. The effect of the thoracic cage on the axial rotation of the apical vertebra was limited. Under different loading conditions, the apical vertebra of both models rotated in the same direction. The magnitude of the vertebral rotation of both models has no statistical significance. Adolescent idiopathic scoliosis can lead to the anatomical changes of the vertebra and the thoracic cage. The corresponding changes of biomechanical features of the scoliotic spine and rib cage would occur. The deformed thoracic cage could not maintain the rotation stability as the normal one.
    Zhonghua wai ke za zhi [Chinese journal of surgery] 11/2010; 48(21):1646-9.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The treatment of adolescent congenital deformity (late-diagnosed congenital deformity) is still unknown. The best candidates for hemivertebra excision are young patients, typically between 4 and 6 years of age. Partial excision may be feasible for older children. The purpose of this study was to assess the effect of unilateral pedicle subtraction osteotomy of hemivertebra for correction of the adolescent congenital spinal deformity. Retrospective analysis. Twelve patients with adolescent congenital deformity who underwent posterior unilateral pedicle subtraction osteotomy and correction were evaluated. Mean age at the time of surgery was 17 years. The charts, standing full-length posteroanterior and lateral view radiographs, and functional measures were reviewed. For evaluation of surgical effectiveness, comparative analysis of the parameters of the total main curve, the segmental curve, the compensatory cranial and caudal curves, the segmental kyphosis, and the trunk shift before and after operation and at the most recent follow-up was done. The mean follow-up period was 40.5 months. Mean Cobb angles of the total main curve and the segmental curve were, respectively, 47.5° and 43.8° before surgery, 23.7° and 16.5° after surgery, and 22.6° and 17° at the last follow-up. The angle of segmental kyphosis was 11.8° before surgery, 6.2° after surgery, and 7.8° (range, -30° to 26°) at the final follow-up. The mean final global lordosis was within the normal range. No neurologic deficit occurred. Solid fusion was achieved for all cases. Unilateral pedicle subtraction osteotomy with instrumentation from a posterior-only approach is indicated in older teenagers for an adolescent congenital spinal deformity. Compared with hemivertebra excision, corrective surgery with hemivertebra osteotomy has a lower intraoperative blood loss and shorter operation time.
    The spine journal: official journal of the North American Spine Society 10/2010; 11(2):111-8. DOI:10.1016/j.spinee.2010.08.028 · 2.80 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To study retrospectively the efficacy and complications of combined pedicle subtraction osteotomy (PSO) and polysegmental closing wedge osteotomy for correction of the severe rigid thoracolumbar kyphotic deformity in ankylosing spondylitis (AS). A total of 8 consecutive male patients with AS and severe thoracolumbar kyphotic deformity (mean age 32 years, range 28 - 46) were involved in this study from August 2004 to June 2007. The average preoperative Cobb angle of thoracic spine (T(1)-T(12)) was 96 degrees (range, 80 degrees - 112 degrees ), the mean preoperative angle of lumbar lordosis (L(1)-S(1)) was 10 degrees (5 degrees - 15 degrees ). The mean chin-brow angle was 47 degrees (range, 40 degrees - 58 degrees ). The average gaze angle was 43 degrees (range, 32 degrees - 50 degrees ). After preoperative assessment, single-level PSO was performed in L(3) vertebrae and two-level polysegmental closing wedge osteotomy was performed in thoracolumbar vertebrae (T(12)-L(1), L(1-2)). Radiographic and clinical results and complications were assessed. The surgical time was (298.1 +/- 20.7) minutes and blood loss during the procedure was (1588.8 +/- 171.6) ml. The follow-up period was (11.5 +/- 7.7) months. The postoperative angle and the amount of correction of the thoracic and lumbar spine were 76.1 degrees +/- 9.6 degrees , 20.3 degrees +/- 1.1 degrees and 48.4 degrees +/- 4.7 degrees , 38.4 degrees +/- 4.7 degrees respectively. The postoperative chin-brow and gaze angle was 16.5 degrees +/- 4.6 degrees and 73.0 degrees +/- 5.2 degrees , respectively. The amount of correction for sagittal balance was (12.3 +/- 1.6) cm. No nerve, vascular injury, stress fracture and coronal decompensation occurred in the patients. Combined PSO and polysegmental closing wedge osteotomy by posterior approach only is safe and effective for correction of the severe rigid thoracolumbar kyphotic deformity in AS. The visual field is significantly improved after surgery.
    Zhonghua wai ke za zhi [Chinese journal of surgery] 06/2009; 47(9):681-4.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Brace application has been reported to be an effective approach in treating mild to moderate idiopathic adolescent scoliosis. However, little attention is focused on the biomechanical study of patient-specific brace treatment. The purpose of this study was to propose a design method of personalized brace and to analyze its biomechanical behavior and to compare the brace forces with the I-Scan measurement system. Based on a three-dimensional patient-specific finite element model of the spine, rib cage, pelvis, and abdomen, a parametric patient-specific model of a thoracolumbosacral orthosis was built. The interaction between the torso and the brace was modeled by surface-to-surface contact interface. Three standard strap tensions (20 N, 40 N, and 60 N) were loaded on the back of the brace to simulate the strap tension. The I-Scan distribution pressure measurement system was used to measure the different region pressures, and the equivalent forces in these regions were calculated. The spinal curve changes and the forces acted on the brace generated by the strap tension were evaluated and compared with the measurement. The reduction in the coronal curvature was about 60% for a strap tension of 60 N. The sacral slope and the lordosis were partially reduced in this case, but the kyphosis had no obvious change. The brace slightly modified the axial rotation at the apex of the scoliotic curve. The forces generated in finite element analysis were approximately in good agreement with the measurement. The design and biomechanical analysis methods of patient-specific brace should be useful in the design of more effective braces.
    Journal of Biomechanical Engineering 05/2009; 131(4):041007. DOI:10.1115/1.3049843 · 1.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Adolescent idiopathic scoliosis (AIS) is a pathological entity of unknown etiology. The causes of osteoporosis or osteopenia in AIS remain undetermined. Whether poor bone quality is an etiologic factor remains controversial. To determine the correlation between low bone mineral status and AIS, a review of literature was performed. After a literature search from 1966 to June 2007 (using Medline, EMBASE, Cochrane DSR, ACP Journal Club, DARE, CCTR, CINAHL and hand searches of references) for studies regarding low bone mineral status and AIS, 20 studies meeting the inclusion criteria were reviewed in terms of the appropriateness of valuation technique, the validity of descriptive system, the number and type of respondents, and overall quality of the studies. Nearly all investigations demonstrated that low bone mineral density (BMD) was a generalized phenomenon and a systematic disorder in AIS. The prevalence of AIS with osteoporosis is approximately 20-38%. The follow-up studies indicated that osteopenia in patients with AIS may be a persistent phenomenon. BMD could be affected by the mechanical loading and lower bone mineral mass is always associated with lower bone strength. The spinal architecture associated with the osteopenia may aggravate the spinal deformity. However, with regard to the concave and convex femoral neck BMD values, and the correlation of BMD to scoliosis parameters, the results remain inconsistent. Bracing may not result in permanent loss of bone mineral mass. The effect of the eccentric tension-compression environments on BMD, the correlation of BMD with scoliosis parameters and the effect of bracing on BMD should be investigated further in prospective, randomized and longitudinal follow-up studies.
    European Spine Journal 09/2008; 17(11):1431-40. DOI:10.1007/s00586-008-0757-z · 2.47 Impact Factor