Publications by authors named "Koji Tamai"

103 Publications

Clinical Comparison of Combined Cortical Bone Trajectory and Transarticular Surface Screw Versus Standard Pedicle Screw Insertion by Wiltse Approach for L5 Isthmic Spondylolisthesis.

Clin Spine Surg 2021 Mar 24. Epub 2021 Mar 24.

Department of Orthopedic Surgery, Osaka City University Graduate School of Medicine, Osaka Department of Orthopedic Surgery, Shimada Hospital, Habikino, Osaka Prefecture, Japan.

Study Design: This was a retrospective cohort study.

Objective: The objective of this study was to assess the effectiveness and invasiveness of a combined screw insertion technique [using cortical bone trajectory (CBT) screw and transarticular surface screw (TASS)] for patients with L5 isthmic spondylolisthesis.

Summary Of Background Data: Lumbosacral posterior fixation using TASS is safe, with high biomechanical strength. However, data regarding its clinical outcomes, effectiveness, and invasiveness, are lacking.

Materials And Methods: This study included 111 patients who underwent single-level L5-S1 posterior lumbar interbody fusion (PLIF) for L5 isthmic spondylolisthesis. The cohort was stratified into 2 groups: the Wiltse group included patients who underwent PLIF between 2008 and 2013 with standard pedicle screw fixation via Wiltse approach and the CBT/TASS group included those who underwent PLIF from 2014 onward with CBT/TASS fixation. After propensity score matching of the CBT/TASS and Wiltse groups, the surgical times, estimated blood loss (EBL), length of in-hospital stays, clinical scores, serum creatine kinase concentration, radiographic parameters, and bone union rate were compared using the χ2 test or Mann-Whitney U test. In addition, multivariate linear regression analyses, with surgical time and EBL as objective variables applied after Box-Cox transformation, were performed.

Results: The matched CBT/TASS group showed significantly shorter surgical times (P<0.001), lower EBL (P=0.032), shorter in-hospital stays (P=0.005), and lower 3-day postoperative serum creatine kinase concentrations (P=0.014) than the matched Wiltse group. However, neither the postoperative grade of spondylolisthesis, the L5-S1 lordotic angle, nor the clinical scores were significantly different between matched groups. The bone union rates were 94.7% and 96.2% in the matched CBT/TASS and Wiltse groups, respectively (P=1.000). Regression analysis showed that CBT/TASS was an independent factor significantly related to shorter surgical times and lower EBL (P<0.001 and P=0.001, respectively).

Conclusion: Compared with Wiltse approach, CBT/TASS is a less invasive technique, with a shorter surgical time and sufficient clinical outcomes for patients with L5 isthmic spondylolisthesis.

Level Of Evidence: Level III-treatment benefits.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BSD.0000000000001170DOI Listing
March 2021

Using artificial intelligence to diagnose fresh osteoporotic vertebral fractures on magnetic resonance images.

Spine J 2021 Mar 13. Epub 2021 Mar 13.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.

Background Context: Accurate diagnosis of osteoporotic vertebral fracture (OVF) is important for improving treatment outcomes; however, the gold standard has not been established yet. A deep-learning approach based on convolutional neural network (CNN) has attracted attention in the medical imaging field.

Purpose: To construct a CNN to detect fresh OVF on magnetic resonance (MR) images.

Study Design/setting: Retrospective analysis of MR images PATIENT SAMPLE: This retrospective study included 814 patients with fresh OVF. For CNN training and validation, 1624 slices of T1-weighted MR image were obtained and used.

Outcome Measure: We plotted the receiver operating characteristic (ROC) curve and calculated the area under the curve (AUC) in order to evaluate the performance of the CNN. Consequently, the sensitivity, specificity, and accuracy of the diagnosis by CNN and that of the two spine surgeons were compared.

Methods: We constructed an optimal model using ensemble method by combining nine types of CNNs to detect fresh OVFs. Furthermore, two spine surgeons independently evaluated 100 vertebrae, which were randomly extracted from test data.

Results: The ensemble method using VGG16, VGG19, DenseNet201, and ResNet50 was the combination with the highest AUC of ROC curves. The AUC was 0.949. The evaluation metrics of the diagnosis (CNN/surgeon 1/surgeon 2) for 100 vertebrae were as follows: sensitivity: 88.1%/88.1%/100%; specificity: 87.9%/86.2%/65.5%; accuracy: 88.0%/87.0%/80.0%.

Conclusions: In detecting fresh OVF using MR images, the performance of the CNN was comparable to that of two spine surgeons.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.spinee.2021.03.006DOI Listing
March 2021

Biglycan expression and its function in human ligamentum flavum.

Sci Rep 2021 Mar 1;11(1):4867. Epub 2021 Mar 1.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi Machi, Abeno-Ku, Osaka, 545-8585, Japan.

Hypertrophy of the ligamentum flavum (LF) is a major cause of lumbar spinal stenosis (LSS), and the pathology involves disruption of elastic fibers, fibrosis with increased cellularity and collagens, and/or calcification. Previous studies have implicated the increased expression of the proteoglycan family in hypertrophied LF. Furthermore, the gene expression profile in a rabbit experimental model of LF hypertrophy revealed that biglycan (BGN) is upregulated in hypertrophied LF by mechanical stress. However, the expression and function of BGN in human LF has not been well elucidated. To investigate the involvement of BGN in the pathomechanism of human ligamentum hypertrophy, first we confirmed increased expression of BGN by immunohistochemistry in the extracellular matrix of hypertrophied LF of LSS patients compared to LF without hypertrophy. Experiments using primary cell cultures revealed that BGN promoted cell proliferation. Furthermore, BGN induces changes in cell morphology and promotes myofibroblastic differentiation and cell migration. These effects are observed for both cells from hypertrophied and non-hypertrophied LF. The present study revealed hyper-expression of BGN in hypertrophied LF and function of increased proteoglycan in LF cells. BGN may play a crucial role in the pathophysiology of LF hypertrophy through cell proliferation, myofibroblastic differentiation, and cell migration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-84363-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7921587PMC
March 2021

Risk factors of the poor long-term prognosis of osteoporotic vertebral fractures: A multicenter cohort study.

J Orthop Surg (Hong Kong) 2021 Jan-Apr;29(1):2309499021994969

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Abeno-ku, Osaka, Japan.

Introduction: The presence of existing osteoporotic vertebral fracture (OVF) increases the mortality risk. However, the influence of the characteristics of OVF is unclear. This study aimed to investigate the influence of new OVF on patients' long-term prognosis using our past cohort study.

Method: This is an extension study of our cohort study carried out between 2005 and 2007. In the present extension study, of 420 patients, 197 whose contact information was available at the 6-month follow-up were included in the telephone survey in 2018. Five patients refused to participate in the survey, and 82 could not be contacted. Eventually, 110 patients were enrolled. Of the Demographic data, radiological findings, medical history, and clinical outcome were investigated at injury onset and at the 6-month follow-up. A proportional hazard model was used to investigate the risk factors for mortality.

Results: Among 110 patients, 33 died. Male sex and low body mass index (BMI <18.5 kg/m) were significant risk factors for mortality [hazard ratio (HR) = 6.40, 1.01-40.50; 5.24, 1.44-19.04, respectively]. The history of stroke and liver disease increased the risk of mortality (HR = 13.37, 1.93-92.7; 6.62, 1.15-38.14, respectively). As regards radiological findings, local kyphosis progression per 1° or ≥7° were significant risk factors of mortality (HR = 1.20, 1.06-1.36; 5.38, 1.81-16.03, respectively).

Conclusions: A telephone survey at 12 years after the occurrence of OVF analyzed risk factors for mortality and showed that a progression of local kyphosis in fractures between injury onset and 6 months after injury was a risk factor of poor prognosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/2309499021994969DOI Listing
February 2021

Expression and function of FGF9 in the hypertrophied ligamentum flavum of lumbar spinal stenosis patients.

Spine J 2021 Feb 10. Epub 2021 Feb 10.

Department of Orthopedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

Background Context: Ligamentum flavum (LF) hypertrophy plays a dominant role in lumbar spinal stenosis (LSS). A previous study found that fibroblast growth factor 9 (FGF9) was upregulated with mechanical stress in rabbit LF. However, the expression and function of FGF9 are not well understood in human LF.

Purpose: To evaluate FGF9 expression and function in human LF with and without hypertrophy.

Study Design: This study employed a basic research study design utilizing human LF tissue for histological analyses.

Patient Samples: Hypertrophied LF tissue sample from patients with LSS, and nonhypertrophied (control) LFs from patients with lumbar disc herniation or other diseases were obtained during surgery.

Methods: LF specimens were histologically analyzed for FGF9 and vascular endothelial growth factor A (VEGF-A) by immunohistochemistry. The number of total and FGF9 immuno-positive cells and blood vessels were counted and compared between LF with and without hypertrophy. For functional analysis, the effect of FGF9 on cell proliferation and migration was examined using a primary cell culture of human LF.

Results: Histological studies revealed that the total cell number was significantly higher in the LF of patients with LSS than in the LF of control patients. Immunohistochemistry showed that the percentage of FGF9-positive cells was significantly higher in the LF of patients with LSS than in the controls, and it positively correlated with patients' age, regardless of disease. Double immune-positive cells for FGF9 and VEGF-A were often observed in vascular endothelial cells and fibroblasts in the fibrotic area of hypertrophied LF, and the number of double positive vessels was significantly higher in LF of LSS patients than in the LF of controls. Primary cell culture of human LF revealed that FGF9 promoted the proliferation and migration of LF cells.

Conclusion: The present study demonstrated that FGF9 expression is highly upregulated in hypertrophied human LF. FGF9 potentially plays a pivotal role in the process of hypertrophy of LF, which is associated with mechanical stress, through cell proliferation and migration.

Clinical Significance: The results from this study partially reveal the molecular mechanisms of LF hypertrophy and suggest that FGF9 may be involved in the process of LF degeneration in elderly patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.spinee.2021.02.004DOI Listing
February 2021

Classification and prognostic factors of residual symptoms after minimally invasive lumbar decompression surgery using a cluster analysis: a 5-year follow-up cohort study.

Eur Spine J 2021 Apr 8;30(4):918-927. Epub 2021 Feb 8.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, Japan.

Purpose: Residual symptoms indicating incomplete remission of lower leg numbness or low back pain may occur after spine surgery. The purpose was to elucidate the pattern of residual symptoms 5 years after minimally invasive lumbar decompression surgery using a cluster analysis.

Methods: The study comprised 193 patients with lumbar spinal stenosis (LSS) (108 men, 85 women) ranging in age from 40 to 86 years (mean, 67.9 years). Each patient underwent 5-year follow-up. The Japanese Orthopedic Association score and visual analog scale scores for low back pain, leg pain, and leg numbness at 5 years were entered into the cluster analysis to characterize postoperative residual symptoms. Other clinical data were analyzed to detect the factors significantly related to each cluster.

Results: The analysis yielded four clusters representing different patterns of residual symptoms. Patients in cluster 1 (57.0%) were substantially improved and had few residual symptoms of LSS. Patients in cluster 2 (11.4%) were poorly improved and had major residual symptoms. Patients in cluster 3 (17.6%) were greatly improved but had mild residual low back pain. Patients in cluster 4 (14.0%) were improved but had severe residual leg numbness. Prognostic factors of cluster 2 were a short maximum walking distance, motor weakness, resting lower leg numbness, cofounding scoliosis, and high sagittal vertical axis.

Conclusions: This is the first study to identify specific patterns of residual symptoms of LSS after decompression surgery. Our results will contribute to acquisition of preoperative informed consent and identification of patients with the best chance of postoperative improvement.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00586-021-06754-yDOI Listing
April 2021

Presence of sarcopenia does not affect the clinical results of balloon kyphoplasty for acute osteoporotic vertebral fracture.

Sci Rep 2021 Jan 8;11(1):122. Epub 2021 Jan 8.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.

Sarcopenia has been associated with poor clinical outcomes in several diseases. Herein, the clinical results of balloon kyphoplasty (BKP) for acute osteoporotic vertebral fracture (OVF) treatment were assessed and compared between sarcopenia and non-sarcopenia patients. Sixty patients who underwent BKP for treatment of acute OVF with poor prognostic factors between April 2016 and September 2017 and were assessed for sarcopenia were enrolled. Clinical results (back pain on visual analogue scale [VAS]; short-form [SF] 36; vertebral deformity; activities of daily living levels; and incidence of adjacent vertebral fractures) were compared between the two groups at 6 months post-BKP. Data analysis revealed that back pain on VAS, SF-36 scores, and vertebral deformity improved from baseline to 6 months after BKP. Thirty-nine patients (65.0%) were diagnosed with sarcopenia and demonstrated a lower body mass index (21.2 vs. 23.3 kg/m, p = 0.02), skeletal muscle mass index (5.32 vs. 6.55 kg/m, p < 0.01), hand-grip strength (14.7 vs. 19.2 kg, p = 0.01), and bone mineral density of the femoral neck (0.57 vs. 0.76 g/cm, p < 0.01) than those of patients without sarcopenia. However, no significant differences were observed in the clinical results between these groups. Therefore, BKP's clinical results for the treatment of acute OVF are not associated with sarcopenia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-80129-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7794449PMC
January 2021

The short-term outcomes of minimally invasive decompression surgery in patients with lumbar ossification or calcification of the ligamentum flavum.

J Neurosurg Spine 2020 Nov 6:1-8. Epub 2020 Nov 6.

1Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine; and.

Objective: Although minimally invasive endoscopic surgery techniques are established standard treatment choices for various degenerative conditions of the lumbar spine, the surgical indications of such techniques for specific cases, such as segments with ossification of the ligamentum flavum (OLF) or calcification of the ligamentum flavum (CLF), remain under investigation. Therefore, the authors aimed to demonstrate the short-term outcomes of minimally invasive endoscopic surgery in patients with degenerative lumbar disease with CLF or OLF.

Methods: This is a retrospective cohort study including consecutive patients who underwent microendoscopic posterior decompression at the authors' institution, where the presence of OLF and CLF did not influence the surgical indication. Fifty-nine patients with OLF and 39 patients with CLF on preoperative CT were identified from the database. Subsequently, two matched control groups (one each matched to the OLF and CLF groups) were created using propensity scores to adjust for age, sex, preoperative Japanese Orthopaedic Association (JOA) score and Oswestry Disability Index, and diagnosis. The background, surgical outcomes, and changes in clinical scores were compared between the matched groups. If there was a significant difference in the improvement of clinical scores, a multivariate linear regression model was applied.

Results: On performing univariate analysis, patients with OLF were found to have a higher body mass index (Mann-Whitney U-test, p = 0.001), higher incidence of preoperative motor weakness (chi-square test, p = 0.019), longer operative time (Mann-Whitney U-test, p < 0.001), and lower improvement in the JOA score (mixed-effects model, p = 0.023) than the matched controls. On performing multivariate analysis, the presence of OLF was identified as an independent variable associated with a poor recovery rate based on the JOA score (multivariate linear regression, p < 0.001). In contrast, there were no significant differences between patients with CLF and their matched controls in terms of preoperative and surgical data and postoperative improvements in clinical scores.

Conclusions: Although the perioperative surgical outcomes, including the surgical complications, and the in-hospital period did not significantly differ, the short-term improvement in the JOA score was significantly lower in patients with degenerative lumbar disease accompanied by OLF than in the patients from the matched control group. In contrast, there were no significant differences in the short-term improvement in clinical scores and perioperative outcomes between patients with CLF and their matched control group. Thus, the surgical indications of minimally invasive posterior decompression for patients with CLF can be the same as those for patients without CLF; however, the indications for patients with OLF should be further investigated in future studies, including the other surgical methods.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3171/2020.6.SPINE20946DOI Listing
November 2020

Time Course of Physical and Mental Well-being Improvements After Cervical Surgery.

Spine (Phila Pa 1976) 2021 Mar;46(5):E303-E309

Department of Orthopedics, Osaka City University Graduate School of Medicine, Osaka, Japan.

Study Design: Retrospective cohort study.

Objective: To elucidate the postoperative time course of improvements in physical and mental well-being in patients with cervical spondylotic myelopathy (CSM).

Summary Of Background Data: Spinal surgeons should understand the postoperative course in detail. However, data are still needed regarding the time course of improvements in well-being, a fundamental aspect of human life, after cervical surgery for CSM.

Methods: One hundred consecutive patients who underwent laminoplasty for CSM, with complete clinical data preoperatively and 3 months and 2 years postoperatively, were enrolled. The Short Form-36 physical component summary (PCS) and mental component summary (MCS) scores were used as parameters of physical and mental well-being, respectively, and 4.0 was defined as the minimal clinically important difference (MCID) for both parameters.

Results: On average, PCS and MCS scores were significantly improved after surgery (P < 0.001, P=0.004, respectively). Moreover, 64 and 48 patients achieved meaningful improvement (>MCID) in PCS and MCS scores at 3 months postoperatively, with maintained improvement (to 2 yr) in 46/64 (71.9%) and 34/48 patients (70.8%), respectively (PCS vs. MCS: P = 0.912). Additionally, 15 of 36 patients (41.7%) and 8 of 52 patients (15.4%) achieved late improvement (meaningful improvement at 2 yr but not at 3 months) in PCS and MCS scores, respectively (PCS vs. MCS: P = 0.007). In multivariate regression analysis, improvement in cJOA score was significantly associated with PCS improvement, but not MCS improvement, at both 3 months and 2 years (P = 0.001, P > 0.001, respectively).

Conclusion: The overall outcome of physical well-being improvement is decided within 3 months postoperatively, in proportion to the recovery in myelopathy, with a relatively high chance of meaningful improvement over the next 21 months. The outcome of improvement in mental well-being is decided within 3 months postoperatively, independently from the recovery in myelopathy, with a low chance of meaningful improvement over the next 21 months.Level of Evidence: 3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BRS.0000000000003787DOI Listing
March 2021

Risk Factor for Poor Patient Satisfaction After Lumbar Spine Surgery in Elderly Patients Aged Over 80 years.

Clin Spine Surg 2020 Oct 13. Epub 2020 Oct 13.

Department of Orthopaedic Surgery, Chiba University, Chiba, Japan.

Study Design: Retrospective cohort study.

Objective: To clarify the poor patient satisfaction after lumbar spinal surgery in elderly patients.

Summary Of Background Data: As the global population continues to age, it is important to consider the surgical outcome and patient satisfaction in the elderly. No studies have assessed patient satisfaction in elderly patients undergoing surgical treatment and risk factors for poor satisfaction in elderly patients after lumbar spinal surgery.

Materials And Methods: A retrospective multicenter survey was performed in 169 patients aged above 80 years who underwent lumbar spinal surgery. Patients were followed up for at least 1 year after surgery. We assessed patient satisfaction from the results of surgery by using a newly developed patient questionnaire. Patients were assessed by demographic data, surgical procedures, complications, reoperation rate, pain improvement, and risk factors for poor patient satisfaction with surgery for lumbar spinal disease.

Results: In total, 131 patients (77.5%, G-group) were satisfied and 38 patients (22.5%, P-group) were dissatisfied with surgery. The 2 groups did not differ significantly in baseline characteristics and surgical data. Postoperative visual analog scale score for low back pain and leg pain were significantly higher in the P-group than in the G-group (low back pain: G-group, 1.7±1.9 vs. P-group, 5.2±2.5, P<0.001; leg pain: G-group, 1.4±2.0 vs. P-group, 5.5±2.6, P<0.001). Multivariate regression analysis revealed that postoperative vertebral fracture (P=0.049; odds ratio, 3.096; 95% confidence interval, 1.004-9.547) and reoperation (P=0.025; odds ratio, 5.692; 95% confidence interval, 1.250-25.913) were significantly associated with the patient satisfaction after lumbar spinal surgery.

Conclusions: Postoperative vertebral fracture and reoperation were found to be risk factors for poor patient satisfaction after lumbar spinal surgery in elderly patients, which suggests a need for careful treatment of osteoporosis in addition to careful determination of surgical indication and procedure in elderly patients.

Level Of Evidence: Level III.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BSD.0000000000001101DOI Listing
October 2020

Can Conventional Magnetic Resonance Imaging Substitute Three-Dimensional Magnetic Resonance Imaging in the Diagnosis of Lumbar Foraminal Stenosis?

Asian Spine J 2020 Oct 19. Epub 2020 Oct 19.

Department of Orthopaedic Surgery, Osaka City University, Osaka, Japan.

Study Design: Retrospective radiological comparative design.

Purpose: To investigate whether conventional magnetic resonance imaging (MRI) could substitute three-dimensional (3D)-MRI for the calculation of the foraminal stenotic ratio (FSR) and clarification of which patients can be assessed more accurately using 3D-MRI.

Overview Of Literature: Previous studies have indicated that 3D-MRI is useful for diagnosing lumbar foraminal stenosis. The FSR obtained using 3D-MRI, described as the ratio of stenosis length, characterized by perineural fat obliteration, to the length of the entire foramen, could indicate the stenosis severity; however, this method is time-consuming and expensive. The FSR also can be calculated using conventional MRI.

Methods: We investigated 154 foramina at L5-S1 in 77 patients. All the patients had degenerative lumbar disorders and had undergone both conventional MRI and 3D-MRI during the same visit. Differences between the FSRs calculated from conventional and 3D-MRI reconstructions and any correlations with the plain radiography findings were assessed.

Results: In foramina that had a FSR of <50% on conventional MRI, the difference between the FSR obtained using conventional MRI and 3D-MRI was 5.1%, with a correlation coefficient of 0.777. For foramina with a FSR ≥50% on conventional MRI, the difference was 20.2%, with a correlation coefficient of 0.54. FSR obtained using 3D-MRI was significantly greater in patients who required surgery than in those who were successfully treated with conservative methods (88% and 42%, respectively). Segments with spondylolisthesis or lateral wedging showed higher FSRs than those without these conditions on both types of MRI.

Conclusions: FSRs <50% obtained using conventional MRI were sufficiently reliable; however, the results were inaccurate for FSRs ≥50%. Patients with high FSRs on 3D-MRI were more likely to require surgical treatment. Therefore, 3D-MRI is recommended in patients with suspected stenosis detected using conventional MRI or plain radiographs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.31616/asj.2020.0133DOI Listing
October 2020

The Surgical Outcomes of Spinal Fusion for Osteoporotic Vertebral Fractures in the Lower Lumbar Spine with a Neurological Deficit.

Spine Surg Relat Res 2020 29;4(3):199-207. Epub 2020 Jan 29.

Department of Orthopaedic Surgery, School of Medicine, International University of Health and Welfare (IUHW), Narita, Japan.

Introduction: Osteoporotic vertebral fracture (OVF) is the most common osteoporotic fracture, and some patients require surgical intervention to improve their impaired activities of daily living with neurological deficits. However, many previous reports have focused on OVF around the thoracolumbar junction, and the surgical outcomes of lumbar OVF have not been thoroughly discussed. We aimed to investigate the surgical outcomes for lumbar OVF with a neurological deficit.

Methods: Patients who underwent fusion surgery for thoracolumbar OVF with a neurological deficit were enrolled at 28 institutions. Clinical information, comorbidities, perioperative complications, Japanese Orthopaedic Association scores, visual analog scale scores, and radiographic parameters were compared between patients with lower lumbar fracture (L3-5) and those with thoracolumbar junction fracture (T10-L2). Each patient with lower lumbar fracture (L group) was matched with to patients with thoracolumbar junction fracture (T group).

Results: A total 403 patients (89 males and 314 females, mean age: 73.8 ± 7.8 years, mean follow-up: 3.9 ± 1.7 years) were included in this study. Lower lumbar OVF was frequently found in patients with lower bone mineral density. After matching, mechanical failure was more frequent in the L group (L group: 64%, T group: 39%; p < 0.001). There was no difference between groups in the clinical and radiographical outcomes, although the rates of complication and revision surgery were still high in both groups.

Conclusions: The surgical intervention for OVF is effective in patients with myelopathy or radiculopathy regardless of the surgical level, although further study is required to improve clinical and radiographical outcomes.

Level Of Evidence: Level III.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.22603/ssrr.2019-0079DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7447347PMC
January 2020

Impact of cervical sagittal balance and cervical spine alignment on craniocervical junction motion: an analysis using upright multi-positional MRI.

Eur Spine J 2021 Feb 7;30(2):444-453. Epub 2020 Aug 7.

Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, 1450 Biggy Street, NRT-4513, Los Angeles, CA, 90033, USA.

Purpose: To evaluate the effect of cervical sagittal alignment on craniocervical junction kinematic.

Methods: We retrospectively reviewed 359 patients (119 cervical lordosis, 38 cervical sagittal imbalances, 111 cervical straight, and 91 cervical kyphosis) who underwent cervical spine multi-positional magnetic resonance imaging (mMRI). The C2-7 angle, disc degeneration grading and cSVA were analyzed in neutral position. The C3-5 OCI, O-C2 angle, and OCD were analyzed in neutral, flexion, and extension position. The Kruskal-Wallis test was used to detect difference among four groups. The post hoc analysis was performed by Mann-Whitney U test.

Results: The cervical sagittal imbalance, cervical straight, and cervical kyphosis groups had significantly more lordosis angle in C3 and C4 OCI and O-C2 angle than the cervical lordosis group (p < 0.0125). Head motion in relation to C2, C3, and C4 (O-C2 angle, C3-4 OCI) in the kyphosis group was significantly greater than in the cervical lordosis group (p < 0.0125). The cervical sagittal imbalance group showed significantly increased O-C2 angle than the cervical lordosis group (p = 0.008). Regression analysis showed that an increase in O-C2 angle by one unit had a relative risk of 4.3% and 3.5% for a patient to be in the cervical sagittal imbalance and cervical kyphosis groups, respectively.

Conclusions: Cervical sagittal alignment affected craniocervical junction motion with the head exhibiting greater extension and motion in the cervical sagittal imbalance and cervical kyphosis groups. Motion of the head in relation to C2 can be used to predict the cervical sagittal alignment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00586-020-06559-5DOI Listing
February 2021

Short- versus long-segment posterior spinal fusion with vertebroplasty for osteoporotic vertebral collapse with neurological impairment in thoracolumbar spine: a multicenter study.

BMC Musculoskelet Disord 2020 Aug 1;21(1):513. Epub 2020 Aug 1.

Department of Orthopaedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.

Background: Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine.

Methods: We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated.

Results: No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group.

Conclusion: Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12891-020-03539-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7395972PMC
August 2020

Residual numbness of the upper extremity after cervical surgery in patients with cervical spondylotic myelopathy.

J Neurosurg Spine 2020 Jul 31:1-8. Epub 2020 Jul 31.

Objective: Although numbness is one of the chief complaints of patients with cervical spondylotic myelopathy (CSM), preoperative factors relating to residual numbness of the upper extremity (UE) and impact of the outcomes on cervical surgery are not well established. The authors hypothesized that severe preoperative UE numbness could be a risk factor for residual UE numbness after surgery and that the residual UE numbness could have a negative impact on postoperative outcomes. Therefore, this study aimed to identify the preoperative factors that are predictive of residual UE numbness after cervical surgery and demonstrate the effects of residual UE numbness on clinical scores and radiographic parameters.

Methods: The study design was a retrospective cohort study. The authors analyzed data of 103 patients who underwent cervical laminoplasty from January 2012 to December 2014 and were followed up for more than 2 years postoperatively. The patients were divided into two groups: the severe residual-numbness group (postoperative visual analog scale [VAS] score for UE numbness > 40 mm) and the no/mild residual-numbness group (VAS score ≤ 40 mm). The outcome measures were VAS score, Japanese Orthopaedic Association scores for cervical myelopathy, physical and mental component summaries of the 36-Item Short-Form Health Survey (SF-36), radiographic film parameters (C2-7 sagittal vertical axis, range of motion, C2-7 lordotic angle, and C7 slope), and MRI findings (severity of cervical canal stenosis, snake-eye appearance, severity of foraminal stenosis). Following univariate analysis, which compared the preoperative factors between groups, the variables with p values < 0.1 were included in the multivariate linear regression analysis. Additionally, the changes in clinical scores and radiographic parameters after 2 years of surgery were compared using a mixed-effects model.

Results: Among 103 patients, 42 (40.8%) had residual UE numbness. In the multivariate analysis, sex and preoperative UE pain were found to be independent variables correlating with residual UE numbness (p = 0.017 and 0.046, respectively). The severity of preoperative UE numbness did not relate to the residual UE numbness (p = 0.153). The improvement in neck pain VAS score and physical component summary of the SF-36 was significantly low in the severe residual-numbness group (p < 0.001 and 0.040, respectively).

Conclusions: Forty-one percent of the CSM patients experienced residual UE numbness for at least 2 years after cervical posterior decompression surgery. Female sex and preoperative severe UE pain were the predictive factors for residual UE numbness. The patients with residual UE numbness showed less improvement of neck pain and lower physical status compared to the patients without numbness.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3171/2020.4.SPINE191566DOI Listing
July 2020

Do rheumatoid arthritis patients have low back pain or radiological lumbar lesions more frequently than the healthy population? - Cross-sectional analysis in a cohort study with age and sex-matched healthy volunteers.

Spine J 2020 12 2;20(12):1995-2002. Epub 2020 Jul 2.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

Background Context: Rheumatoid arthritis (RA) can affect the spine; however, the epidemiology of lumbar lesions and/or low back pain (LBP) in RA patients has not been well-studied.

Purpose: The purpose of this study was to compare the prevalence of lumbar lesions and LBP in RA patients with that in healthy volunteers, and to elucidate the influence of RA on lumbar disease.

Study Design: Cross-sectional analysis in a cohort study with age- and sex-matched healthy volunteers.

Patient Sample: This study included 185 patients with RA and 188 gender/age-matched healthy volunteers without RA.

Outcome Measures: Lumbar spondylolisthesis and prevalent vertebral fractures were evaluated using plain lateral X-ray images. Thoraco-lumbar scoliosis was evaluated using dual-energy X-ray absorptiometric images. LBP was assessed using the visual analogue scale (VAS) and Rolland-Morris disability questionnaire (RDQ).

Methods: The prevalence of radiological lumbar lesion and LBP was compared between the RA and control groups. In the RA group, factors associated with lumbar lesion and LBP were analyzed using a multiple logistic regression model.

Results: The prevalence rates of spondylolisthesis and prevalent vertebral fracture were significantly higher in the RA group than in the control group; the prevalence of thoraco-lumbar scoliosis tended to be higher in the RA group. There was no significant difference in the average LBP-VAS between the groups. However, the percentage of analgesic drug use was significantly higher, and RDQ scores tended to be worse in the RA group than the control group. Multivariate analysis revealed that age and disease activity score were both related to LBP in the RA group.

Conclusions: RA patients are more likely to have radiological lumbar lesions. LBP in RA patients is well controlled, similar to the level in the healthy population; however, disease activity was related to LBP in RA patients. These results suggest that disease control is important for lumbar care in RA patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.spinee.2020.06.020DOI Listing
December 2020

Effect of bisphosphonates or teriparatide on mechanical complications after posterior instrumented fusion for osteoporotic vertebral fracture: a multi-center retrospective study.

BMC Musculoskelet Disord 2020 Jul 1;21(1):420. Epub 2020 Jul 1.

Department of Orthopaedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.

Background: The optimal treatment of osteoporosis after reconstruction surgery for osteoporotic vertebral fractures (OVF) remains unclear. In this multicentre retrospective study, we investigated the effects of typically used agents for osteoporosis, namely, bisphosphonates (BP) and teriparatide (TP), on surgical results in patients with osteoporotic vertebral fractures.

Methods: Retrospectively registered data were collected from 27 universities and affiliated hospitals in Japan. We compared the effects of BP vs TP on postoperative mechanical complication rates, implant-related reoperation rates, and clinical outcomes in patients who underwent posterior instrumented fusion for OVF. Data were analysed according to whether the osteoporosis was primary or glucocorticoid-induced.

Results: A total of 159 patients who underwent posterior instrumented fusion for OVF were included. The overall mechanical complication rate was significantly lower in the TP group than in the BP group (BP vs TP: 73.1% vs 58.2%, p = 0.045). The screw backout rate was significantly lower and the rates of new vertebral fractures and pseudoarthrosis tended to be lower in the TP group than in the BP group. However, there were no significant differences in lumbar functional scores and visual analogue scale pain scores or in implant-related reoperation rates between the two groups. The incidence of pseudoarthrosis was significantly higher in patients with glucocorticoid-induced osteoporosis (GIOP) than in those with primary osteoporosis; however, the pseudoarthrosis rate was reduced by using TP. The use of TP also tended to reduce the overall mechanical complication rate in both primary osteoporosis and GIOP.

Conclusions: The overall mechanical complication rate was lower in patients who received TP than in those who received a BP postoperatively, regardless of type of osteoporosis. The incidence of pseudoarthrosis was significantly higher in patients with GIOP, but the use of TP reduced the rate of pseudoarthrosis in GIOP patients. The use of TP was effective to reduce postoperative complications for OVF patients treated with posterior fusion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12891-020-03452-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7331246PMC
July 2020

The Severity of Cervical Disc Degeneration Does Not Impact 2-year Postoperative Outcomes in Patients With Cervical Spondylotic Myelopathy Who Underwent Laminoplasty.

Spine (Phila Pa 1976) 2020 Sep;45(18):E1142-E1149

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

Study Design: Retrospective cohort study.

Objective: The aim of this study was to evaluate the impact of cervical disc degeneration (CDD) severity on 2-year postoperative outcomes following laminoplasty.

Summary Of Background Data: The impact of CDD on postoperative outcomes of cervical laminoplasty has not been well established.

Methods: A total of 144 patients who underwent open-door laminoplasty for cervical spondylotic myelopathy (CSM) were enrolled. Six cervical discs were independently analyzed for degeneration severity using a previously reported grading system (grade 0: none, grade 3: severest). The relationship between the segmental range of motion (ROM) and the severity of CDD was evaluated. Subsequently, after dividing overall patients into mild and severe CDD groups by the average of CDD scores, the mixed-effect model was applied to assess 2-year postoperative outcomes, including physician-assessed myelopathy scores, patient-reported outcomes, and preoperative radiographic parameters. Finally, as additional analysis, the severe CDD group was further divided into two groups: group 1 included patients with a grade 3 CDD change in their most stenotic level and group 2 included the others. The 2-year postoperative myelopathy score was compared between groups 1 and 2.

Results: The cervical segments with grade 3 CDD showed significantly smaller ROM compared with those with grade 0, 1, or 2 CDD (P < 0.01). There were no significant differences in postoperative improvements in myelopathy, pain, patient-reported physical and mental status, and radiographic parameters, except for quality of life (QOL) scores between CDD groups. A significant (P = 0.02) postoperative improvement in QOL scores was noted in the severe CDD group. In an additional analysis, myelopathy score at 2 years postoperatively was significantly higher in group 1 than group 2 (P = 0.041).

Conclusion: The severity of CDD did not negatively impact 2-year postoperative laminoplasty outcomes. The postulated reason is that the decreased segmental instability in the level with severe CDD may affect surgical outcomes positively.

Level Of Evidence: 3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BRS.0000000000003528DOI Listing
September 2020

Impact of High-intensity Zones on Their Corresponding Lumbar Spine Segments: A Propensity Score-matched Analysis.

Clin Spine Surg 2021 Feb;34(1):32-38

Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA.

Study Design: Retrospective radiographic study.

Objective: The aim of this study was to compare disks with and without high-intensity zones (HIZ) to understand the impact of an HIZ on the stability of corresponding lumbar spinal segments.

Summary Of Background Data: Previous studies have established a relationship between back pain and the presence of HIZ on T2-weighted images of magnetic resonance imaging. These previous studies, however, used either plain radiographs or static (neutral position) magnetic resonance imaging to assess their chosen variables.

Materials And Methods: We retrospectively reviewed 140 consecutive patients with MR images taken in weight-bearing neutral, flexion, and extension positions. We separated segments into those with HIZ and without HIZ and assessed the grade of disk degeneration for each segment. Subsequently, a matched control group was selected from the segments without HIZ. Multiple factors were compared in a univariate analysis. A multinomial logistic regression analysis was conducted to assess the association between angular range of motion (ROM) >10 degrees and translational motion >2 mm with multiple independent variables.

Results: Upon assessment of the 700 lumbar segments, 70 (10%) segments had an HIZ and 68 patients had a single HIZ. On univariate analysis, the presence of an HIZ was not found to be significantly associated with degree of fatty muscle degeneration (P=0.969), muscle volume (P=0.646), degree of facet joint osteoarthritis (P=0.706), intervertebral disk height (P=0.077), Modic change (P=0.951), lower endplate shape (P=0.702), upper endplate shape (P=0.655), or degree of disk degeneration (P=0.607). Multifactorial analysis showed that none of the independent variables significantly correlated with angular ROM >10 degrees. For translational motion, the only significant correlation was the Goutallier classification (P=0.017).

Conclusions: The presence of HIZ did not significantly affect spinal stability as measured by angular ROM and translational motion and was not associated with significant changes in several quantitative measurements of spine pathology.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BSD.0000000000000991DOI Listing
February 2021

The effect of nicotine cessation on human bone marrow stem cell proliferation and differentiation into osteoblasts.

Spine J 2020 02;20(2):307-309

Department of Orthopedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.spinee.2019.09.016DOI Listing
February 2020

Patient-reported outcomes for cervical disease in end-stage renal disease patients: Propensity matching analysis using volunteer data.

J Clin Neurosci 2020 Feb 6;72:130-133. Epub 2020 Jan 6.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Japan.

As the number of patients with end-stage renal disease (ESRD) has been increasing, the number of cervical spine surgeries for the patients with ESRD has also been increasing. The purpose is to identify the differences in cervical disease-specific patient-reported outcomes (PROs) between a healthy population and patients with ESRD, adjusting for subjects' age and physical activity.

Methods: The ESRD group included patients with ESRD who were treated with hemodialysis in our outpatient clinic and healthy volunteers were individuals who attended public health lectures. Volunteers with a history of cervical disease were excluded. All participants answered the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) and questionnaires that evaluate the disability in performing physical activities.

Results: A total of 111 participants were enrolled and divided into the ESRD group (n = 40) and the control group (n = 71). After adjusting for age and sex using propensity score, cervical function (p = 0.008), lower-extremity function (p = 0.007), and QOL (p < 0.001) in patients in the adjusted ESRD group were significantly lower than those in the control group. In multivariate linear regression, the use of hemodialysis was a significant variable that was negatively related to lower-extremity function (p = 0.004) and QOL (p = 0.011) independent of age and disability in performing physical activity.

Conclusion: The ESRD was a significant negative factor of lower-extremity function and QOL, independent of age, sex, and disability in performing physical activity. These results can help understand the cervical status of patients with ESRD and adjust the goal for such patients after cervical surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jocn.2019.12.045DOI Listing
February 2020

Characteristic radiological findings for revision surgery after balloon kyphoplasty.

Sci Rep 2019 12 6;9(1):18513. Epub 2019 Dec 6.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

Balloon kyphoplasty (BKP) sometimes fails to improve patients' outcomes, with revision surgery, using anterior or posterior reconstruction, being required. The purpose of this study was to investigate the radiological risk factors of failure after BKP in the treatment of osteoporotic vertebral fractures (OVFs). This case-control study included 105 patients treated with single BKP and 14 patients  who required revision BKP. We evaluated radiological findings differentiating both groups, using plain radiography and computed tomography, before BKP. Angular flexion-extension motion was significantly greater in the revision than BKP group. While the frequency of pedicle fracture and posterior wall injury was not different between the groups, a split type fracture was more frequent in the revision group. Split type fracture had the highest adjusted odds ratio (OR) for revision (16.5, p = 0.018). Angular motion ≥14° increased the risk for revision surgery by 6-fold (p = 0.013), with endplate deficit having an OR of revision of 5.0 (p = 0.032). The revision rate after BKP was 3.8%, with split type fracture, greater angular motion and large endplate deficit being risk factors for revision. Treatment strategies for patients with these risk factors should be carefully evaluated, considering the inherent difficulties in performing revision surgery after BKP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-55054-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6898586PMC
December 2019

Improvement in Patient Mental Well-being After Surgery for Cervical Spondylotic Myelopathy.

Spine (Phila Pa 1976) 2020 May;45(10):E568-E575

Department of Orthopedics, Osaka City University Graduate School of Medicine, Asahimachi, Abenoku, Osaka, Japan.

Study Design: Retrospective cohort study.

Objective: The aim of this study was to investigate changes in mental well-being after surgery for cervical spondylotic myelopathy (CSM) and identify factors associated with improvement.

Summary Of Background Data: Posterior cervical surgery with laminoplasty significantly improves myelopathy and physical function in patients with CSM. However, its impact on mental well-being is unclear.

Methods: Patients who underwent laminoplasty for CSM and had >2 years of follow-up were reviewed (n = 111). The mental component summary (MCS) score was used as a measure of mental well-being. The trend in MCS score change was evaluated using the Jonckheere-Terpstra trend test. Preoperative clinical scores were compared between patients with improvements greater and less than the minimal clinically important difference (MCID). Significant variables were included in a multinomial logistic regression analysis and further validated in a receiver-operating characteristic (ROC) curve analysis. Additionally, the results were confirmed in a long-term observation cohort of patients followed up for >5 years (n = 46).

Results: The improvement in the average MCS score (5.6) was greater than the MCID (4.0). The trend of improvement was sustained for 2 years (P = 0.002), but not for 5 years (P = 0.130). In terms of individual cases, 56 patients (50.5%) achieved MCS score improvement greater than the MCID. These patients showed significantly lower preoperative MCS scores than those without meaningful improvement (P < 0.001). The preoperative "social functioning (SF)" score was independently associated with MCS score improvement (P = 0.001). ROC curve analysis validated the ability of preoperative SF to predict MCS score improvement at 2 and 5 years postoperatively (area under the curve: 0.744, 0.893, respectively).

Conclusion: Half of the patients achieved meaningful improvement in mental well-being. A lower preoperative SF score was independently associated with improvement. These results may help identify patients who could experience an improvement in mental well-being after surgery and develop novel approaches to achieve further improvement.

Level Of Evidence: 3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/BRS.0000000000003337DOI Listing
May 2020

Surgical Treatment of Osteoporotic Vertebral Fracture with Neurological Deficit-A Nationwide Multicenter Study in Japan.

Spine Surg Relat Res 2019 22;3(4):361-367. Epub 2019 Mar 22.

Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo, Japan.

Introduction: The prevalence of patients with osteoporosis continues to increase in aging societies, including Japan. The first choice for managing osteoporotic vertebral compression fracture (OVF) is conservative treatment. Failure in conservative treatment for OVF may lead to non-union or vertebral collapse, resulting in neurological deficit and subsequently requiring surgical intervention. This multicenter nationwide study in Japan was conducted to comprehensively understand the outcomes of surgical treatments for OVF non-union.

Methods: This multicenter, retrospective study included 403 patients (89 males, 314 females, mean age 73.8 ± 7.8 years, mean follow-up 3.9 ± 1.7 years) with neurological deficit due to vertebral collapse or non-union after OVF at T10-L5 who underwent fusion surgery with a minimum 1-year follow-up. Radiological and clinical outcomes at baseline and at the final follow-up (FU) were evaluated.

Results: OVF was present at a thoracolumbar junction such as T12 (124 patients) and L1 (117 patients). A majority of OVF occurred after a minor trauma, such as falling down (55.3%) or lifting objects (8.4%). Short segment fusion, including affected vertebra, was conducted (mean 4.0 ± 2.0 vertebrae) with 256.8 minutes of surgery and 676.1 g of blood loss. A posterior approach was employed in 86.6% of the patients, followed by a combined anterior and posterior (8.7%), and an anterior (4.7%) approach. Perioperative complications and implant failures were observed in 18.1% and 41.2%, respectively. VAS scores of low back pain (74.7 to 30.8 mm) and leg pain (56.8 to 20.7 mm) improved significantly at FU. Preoperatively, 52.6% of the patients were unable to walk and the rate of non-ambulatory patients decreased to 7.5% at FU.

Conclusions: This study demonstrated that substantial improvement in activity of daily living (ADL) was achieved by fusion surgery. Although there was a considerable rate of complications, fusion surgery is beneficial for elderly OVF patients with non-union.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.22603/ssrr.2019-0004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6834469PMC
March 2019

Impact of Sarcopenia on Clinical Outcomes of Minimally Invasive Lumbar Decompression Surgery.

Sci Rep 2019 11 12;9(1):16619. Epub 2019 Nov 12.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

The purpose of this study was to clarify the clinical impact of sarcopenia on the outcome of minimally invasive lumbar decompression surgery. The records of 130 patients who were >65 years and underwent minimally invasive lumbar decompression surgery were retrospectively reviewed. We collected the Japanese Orthopaedic Association (JOA) score before surgery and at the final follow-up and measured appendicular muscle mass using bioimpedance analysis, hand-grip strength and gait speed. We diagnosed the patients with sarcopenia, dynapenia and normal stages using the European Working Group on Sarcopenia in Older People definition and used cutoff thresholds according to the algorithm set by the Asian Working Group for Sarcopenia. The average age of patients undergoing surgery was 76.9 years old. The JOA score improved from 12.6 points preoperatively to 24.3 points at final follow up. The prevalence of the sarcopenia, dynapenia and normal stages was 20.0, 31.6 and 43.8%. Clinical outcomes, such as JOA score, JOA score improvement ratio, visual analog scale for low back pain, leg pain and numbness, were not significantly different among each group. Multiple regression analysis showed that preoperative JOA score and low physical performance (low gait speed) were independently associated with poor clinical outcomes. The JOA score improved after minimally invasive lumbar decompression surgery even when the patients were diagnosed as being at different stages of sarcopenia. Low physical performance had the greater clinical impact on the clinical outcome of lumbar surgery than low skeletal muscle index.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-53053-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6851360PMC
November 2019

Complications after spinal fixation surgery for osteoporotic vertebral collapse with neurological deficits: Japan Association of Spine Surgeons with ambition multicenter study.

J Orthop Sci 2019 Nov 11;24(6):985-990. Epub 2019 Sep 11.

Spine and Spinal Cord Center, International University of Health and Welfare, Mita Hospital, Tokyo, Japan.

Background: There have been few reports on the incidence and risk factors of the complications after spinal fixation surgery for osteoporotic vertebral collapse (OVC) with neurological deficits. This study aimed to identify the incidence and risk factors of the complications after OVC surgery.

Methods: In this retrospective multicenter study, a total of 403 patients (314 women and 89 men; mean age 73.8 years) who underwent spinal fixation surgery for OVC with neurological deficits between 2005 and 2014 were enrolled. Data on patient demographics were collected, including age, sex, body mass index, smoking, steroid use, medical comorbidities, and surgical procedures. All postoperative complications that occurred within 6 weeks were recorded. Patients were classified into two groups, namely, complication group and no complication group, and risk factors for postoperative complications were investigated by univariate and multivariate analyses.

Results: Postoperative complications occurred in 57 patients (14.1%), and the most common complication was delirium (5.7%). In the univariate analysis, the complication group was found to be older (p = 0.039) and predominantly male (p = 0.049), with higher occurrence rate of liver disease (p = 0.001) and Parkinson's disease (p = 0.039) compared with the no-complication group. In the multivariate analysis, the significant independent risk factors were age (p = 0.021; odds ratio [OR] 1.051, 95% confidence interval [CI] 1.007-1.097), liver disease (p < 0.001; OR 8.993, 95% CI 2.882-28.065), and Parkinson's disease (p = 0.009; OR 3.636, 95% CI 1.378-9.599).

Conclusions: Complications after spinal fixation surgery for OVC with neurological deficits occurred in 14.1%. Age, liver disease, and Parkinson's disease were demonstrated to be independent risk factors for postoperative complications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jos.2019.08.015DOI Listing
November 2019

Surgical outcomes of spinal fusion for osteoporotic vertebral fracture in the thoracolumbar spine: Comprehensive evaluations of 5 typical surgical fusion techniques.

J Orthop Sci 2019 Nov 21;24(6):1020-1026. Epub 2019 Aug 21.

Department of Orthopaedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan; Department of Orthopaedic Surgery, International University of Health and Welfare, Mita, Minato-ku, Tokyo, 108-8329, Japan.

Background: A consensus on the optimal surgical procedure for thoracolumbar OVF has yet to be reached due to the previous relatively small number of case series. The study was conducted to investigate surgical outcomes for osteoporotic vertebral fracture (OVF) in the thoracolumbar spine.

Methods: In total, 315 OVF patients (mean age, 74 years; 68 men and 247 women) with neurological symptoms who underwent spinal fusion with a minimum 2-year follow-up were included. The patients were divided into 5 groups by procedure: anterior spinal fusion alone (ASF group, n = 19), anterior/posterior combined fusion (APSF group, n = 27), posterior spinal fusion alone (PSF group, n = 40), PSF with 3-column osteotomy (3CO group, n = 92), and PSF with vertebroplasty (VP + PSF group, n = 137).

Results: Mean operation time was longer in the APSF group (p < 0.05), and intraoperative blood loss was lower in the VP + PSF group (p < 0.05). The amount of local kyphosis correction was greater in the APSF and 3CO groups (p < 0.05). Clinical outcomes were approximately equivalent among all groups.

Conclusion: All 5 procedures resulted in acceptable neurological outcomes and functional improvement in walking ability. Moreover, they were similar with regard to complication rates, prevalence of mechanical failure related to the instrumentation, and subsequent vertebral fracture. Individual surgical techniques can be adapted to suit patient condition or severity of OVF.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jos.2019.07.018DOI Listing
November 2019

Risk Factors for Proximal Junctional Fracture Following Fusion Surgery for Osteoporotic Vertebral Collapse with Delayed Neurological Deficits: A Retrospective Cohort Study of 403 Patients.

Spine Surg Relat Res 2019 Apr 19;3(2):171-177. Epub 2018 Oct 19.

Department of Orthopaedic Surgery, Keio University, Tokyo, Japan.

Introduction: Approximately 3% of osteoporotic vertebral fractures develop osteoporotic vertebral collapse (OVC) with neurological deficits, and such patients are recommended to be treated surgically. However, a proximal junctional fracture (PJFr) following surgery for OVC can be a serious concern. Therefore, the aim of this study is to identify the incidence and risk factors of PJFr following fusion surgery for OVC.

Methods: This study retrospectively analyzed registry data collected from facilities belonging to the Japan Association of Spine Surgeons with Ambition (JASA) in 2016. We retrospectively analyzed 403 patients who suffered neurological deficits due to OVC below T10 and underwent corrective surgery; only those followed up for ≥2 years were included. Potential risk factors related to the PJFr and their cut-off values were calculated using multivariate logistic regression analysis and receiver operating characteristic (ROC) analysis.

Results: Sixty-three patients (15.6%) suffered PJFr during the follow-up (mean 45.7 months). In multivariate analysis, the grade of osteoporosis (grade 2, 3: adjusted odds ratio (aOR) 2.92; p=0.001) and lower instrumented vertebra (LIV) level (sacrum: aOR 6.75; p=0.003) were independent factors. ROC analysis demonstrated that lumbar bone mineral density (BMD) was a predictive factor (area under curve: 0.72, p=0.035) with optimal cut-off value of 0.61 g/cm (sensitivity, 76.5%; specificity, 58.3%), but that of the hip was not (p=0.228).

Conclusions: PJFr was found in 16% cases within 4 years after surgery; independent risk factors were severe osteoporosis and extended fusion to the sacrum. The lumbar BMD with cut-off value 0.61 g/cm may potentially predict PJFr. Our findings can help surgeons select perioperative adjuvant therapy, as well as a surgical strategy to prevent PJFr following surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.22603/ssrr.2018-0068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6690093PMC
April 2019

Impact of Hemodialysis on Surgical Outcomes and Mortality Rate after Lumbar Spine Surgery: A Matched Cohort Study.

Spine Surg Relat Res 2019 Apr 25;3(2):151-156. Epub 2018 Aug 25.

Department of Orthopaedic Surgery, Osaka City University Graduate School of Medicine, Osaka, Japan.

Introduction: Despite ongoing improvements in both dialysis and surgical techniques, spinal surgery in patients undergoing hemodialysis (HD) is a challenge to surgeons because of the high mortality rate. However, no previous studies have examined clinical outcomes after lumbar surgery in HD patients. The purpose of this study is to compare clinical outcomes and complication rates after lumbar spinal surgery in patients with or without hemodialysis.

Methods: This retrospective, matched cohort study was conducted to compare surgical outcomes between HD vs non-HD patients who underwent lumbar surgery at our hospital. Controls were individually matched to cases at a ratio of 1:2. Clinical outcomes, complications, and mortality rates were compared between the two groups.

Results: Twenty-nine patients in the HD group and 57 in the non-HD group were included in the current study. Five patients in the HD group died during the follow-up period, whereas no patients died in the non-HD group (mortality rate, 17.2% vs. 0%, = 0.003). Japanese Orthopaedic Association (JOA) scores were significantly less improved in the HD group than in the non-HD group (11.9 vs. 14.2 preoperatively, = 0.001; 19.9 vs. 25.1 at final follow-up, < 0.001). Five patients underwent repeat surgery in the HD group, which was significantly higher than the non-HD group (17.2% vs. 3.5%, = 0.041).

Conclusions: The current study indicates that patients undergoing HD had poor outcomes after lumbar spinal surgery. Moreover, 5 of 29 patients died within a mean 2.4-years follow-up. The indications for lumbar spine surgery in HD patients must be carefully considered because of poor surgical outcomes and high mortality rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.22603/ssrr.2018-0025DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6690081PMC
April 2019