Permsak Paholpak
University of Southern California
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European Spine Journal | 2017
Phillip Grisdela; Zorica Buser; Anthony D’Oro; Permsak Paholpak; John C. Liu; Jeffrey C. Wang
PurposeThis study defined the incidence and trends of surgeries performed for patients with cervical disc degeneration with and without tobacco use disorder (TUD).MethodsThis study utilized the Humana Inc. database between 2007 and 2013 to identify patients with cervical disc degeneration with or without myelopathy. International Classification of Diseases, ninth revision (ICD-9) and Current Procedural Terminology (CPT) codes determined the initial diagnosis of disc degeneration, myelopathy status and TUD, whether patients received surgery, and TUD status at surgery.ResultsThe prevalence of disc degeneration with myelopathy increased by 32.8% between 2007 and 2013, while disc disease with myelopathy and TUD increased by 91.6%. For patients without myelopathy, the prevalence of disc degeneration alone increased by 65.4%, and disc degeneration with myelopathy increased by 148.7%. Of myelopathy patients, 1717 (6.4%) had TUD and 1024 (59.6%) received surgery, compared to 6508 patients without TUD (26.1%). For patients without myelopathy, 11,337 (3.5%) had TUD and 787 (6.9%) underwent surgery, compared to 9716 patients (3%) without TUD. Of surgical patients, 781 (76.3%) with myelopathy and TUD still had a TUD diagnosis at surgery, and 542 (68.9%) of patients without myelopathy still had a TUD diagnosis at surgery.ConclusionsThe prevalence of degenerative disc disease and TUD has increased more than disc disease alone. Patients with TUD were more likely to get surgery, and to have surgeries earlier than patients without TUD. Patients with TUD at the time of the diagnosis of their disc degeneration likely still had a TUD diagnosis at the time of surgery.
European Journal of Radiology | 2018
Permsak Paholpak; Emin Dedeogullari; Christopher Lee; Koji Tamai; Kaku Barkoh; Kittipong Sessumpun; Jeffrey C. Wang; Zorica Buser
The objective of the study is to identified the correlation between Modic changes (MCs), disc degeneration, motions (translation and angulation) and facet osteoarthritis in lumbar spine. 425 patients who underwent multi-positional lumbar MRI were reviewed. A total of 2250 lumbar spinal segments in neutral position were evaluated for MCs, disc degeneration grading, translation and angulation motion, and facet osteoarthritis. The chi-square test, Kruskal-Wallis, Mann-Whitney U test, Pearsons correlation and linear regression were used to test for statistically significant difference between parameters. MCs type 2 showed the most translational motion. The presence of MCs was significantly correlated with advanced disc degeneration (grade 4-5, Odds ratio 6.29, 95% CI 4.48-8.83) and the presence of facet osteoarthritis (Odds ratio 9.50, 95% CI 6.18-14.62). The presence of facet osteoarthritis had significantly more translation motion than non-osteoarthritis facet (p=0.04). The facet osteoarthritis grade was positively correlated with disc degeneration grade (r=0.309, p-value<0.001). The facet osteoarthritis correlated with the presence of MCs and more translation motion. The severity of facet osteoarthritis was correlated with the advanced disc degeneration. The MCs, translation motion, and disc degeneration were the significant parameters which affected lumbar facet osteoarthritis.
The Spine Journal | 2017
Permsak Paholpak; Alexander Nazareth; Patrick C. Hsieh; Zorica Buser; Jeffrey C. Wang
BACKGROUND CONTEXT T1 slope is a novel thoracic parameter used to assess cervical spine sagittal balance. Thoracic index (TI) parameters including T1 slope and cervical sagittal alignment parameters may play an important role in degenerative cervical spondylolisthesis (DCS). Current literature regarding the relationship between TI and cervical sagittal alignment parameters in patients with DCS is limited. PURPOSE (1) To evaluate the T1 slope, cervical sagittal alignment, and thoracic inlet parameter in patients with DCS using kinematic magnetic resonance imaging (kMRI), and (2) to find a correlation between the T1 slope, TI, and other cervical sagittal parameters in patients with DCS. DESIGN/SETTING Retrospective kMRI study, Level III. PATIENT SAMPLE Fifty-two patients with DCS from 1,128 patients from a cervical kMRI database. OUTCOME MEASURES T1 slope, C2-C7 angle, sagittal vertical axis C2-C7 (SVA C2-C7), cranial tilt, cervical tilt, neck tilt, and thoracic inlet angle (TIA). METHODS Cervical spine kMRIs of 52 patients with DCS (mean age 51.7±standard deviation) were analyzed in neutral, flexion, and extension positions. Patients with DCS were divided into two groups: anterolisthesis (N=33) and retrolisthesis (N=19). Each listhesis group was subclassified into grade 1 (slip 2-3 mm) and grade 2 (slip>3 mm). RESULTS Grade 2 retrolisthesis had the largest T1 slope followed by grade 1 retrolisthesis, grade 2 anterolisthesis, and grade 1 anterolisthesis. Significant differences were found between the anterolisthesis and the retrolisthesis groups in the neutral position (p=.025). The flexion position had the largest T1 slope and showed a significant difference with anterolisthesis in the neutral position (p=.041). Sagittal vertical axis C2-C7 showed strong correlation with cranial tilt in all DCS groups and all positions. CONCLUSIONS In our study, T1 slope was larger in grade 2 DCS, and the retrolisthesis group had larger T1 slope than the anterolisthesis group. Presence of larger T1 slope was significantly correlated with larger cervical lordosis curvature. Furthermore, cranial tilt was strongly correlated with SVA C2-C7.
Journal of Clinical Neuroscience | 2017
Permsak Paholpak; Alexander Nazareth; Kaku Barkoh; Larry Lee; Joshua Lucas; Zorica Buser; Jeffrey C. Wang
The objective was to evaluate motion, disc degeneration and Space Available for Cord (SAC) at the adjacent segments of degenerative cervical spondylolisthesis (DCS) using kinematic Magnetic Resonance Imaging (kMRI). The cervical spine kMRI of sixty-one DCS spinal levels (38 anterolisthesis and 23 retrolisthesis) were analyzed at the listhesis level and its adjacent segments in three position using kMRI. MRAnalyzer3 was used to analyze translation, angular motion and SAC. The caudad level had significantly less translation motion than the listhesis level in overall DCS or grade 2 anterolisthesis group (P<0.05). The cephalad level had significant more translational motion than the caudad level in overall DCS or grade 1 retrolisthesis group (P<0.05). For disc degeneration, the cephalad level had the least disc degeneration and showed significant difference with the listhesis level in overall DCS or overall anterolisthesis or overall retrolisthesis or grade 2 anterolisthesis or grade 1 or 2 retrolisthesis (P<0.05). For SAC, the listhesis level had the narrowest space in overall DCS groups. In neutral position, grade 1 anterolisthesis had significantly larger SAC at the listhesis and the cephalad level than grade 1 retrolisthesis (P<0.05). In conclusion, DCS affected cervical spine motion and kinematics. Grade 1 retrolisthesis showed tendency of narrower SAC at the cephalad level more than the same grade anterolisthesis. The likelihood of the adjacent segment disease and spinal cord compression are higher in both grade 2 anterolisthesis and retrolisthesis.
The Spine Journal | 2018
Koji Tamai; Joshua Romanu; Phillip Grisdela; Permsak Paholpak; Pengfei Zheng; Hiroaki Nakamura; Zorica Buser; Jeffrey C. Wang
BACKGROUND CONTEXT Cervical sagittal vertical axis (cSVA) of ≥40 mm is recognized as the key factor of poor health-related quality of life, poor surgical outcomes, and correction loss after surgery for cervical deformity. However, little is known about the radiological characteristics of patients with cSVA≥40 mm. PURPOSE The purpose of this study was to identify the radiological characteristics of patients with cervical imbalance. DESIGN Retrospective analysis of weight-bearing cervical magnetic resonance (MR) images. PATIENT SAMPLE Consecutive 1,500 MR images of symptomatic patients in weight-bearing position. OUTCOME MEASURES Cervical sagittal vertical axis, cervical alignment, cervical balance parameters (T1 slope, Co-C2 angle, C2-C7 angle, C7-T1 angle, neck tilt, and thoracic inlet angle), disc degeneration (Pfirmann and Suzuki classification), end plate degeneration (Modic change), spondylolisthesis (antero- and retrolisthesis), anteroposterior (AP) diameter of dural sac, cross-sectional area (CSA), and fat infiltration ratio of the transversospinalis muscles at C4 and C7 levels. METHODS Patients were divided into two groups: cSVA≥40 mm and cSVA<40 mm. Gender, age, and cervical alignment were analyzed. Subsequently, matched imbalance (cSVA≥40 mm) and control (<40 mm) groups were created using the propensity score to adjust for age, gender, and cervical alignment. Cervicothoracic angular parameters, disc degeneration, Modic change, spondylolisthesis, and degeneration of the transversospinalis muscles at C4 and C7 were compared. Variables with p<.05 were included in the multinomial logistic regression model to identify factors that relate to the cervical balance grouping. RESULTS The incidence of patients with cervical imbalance was 2.5% (37 patients). Those patients had a higher incidence of kyphosis, were older, and there were more male patients. In the matched imbalance group, the T1 slope was greater (p=.028), C7-T1 lordotic angle was smaller (p<.001), the number of anterolisthesis was greater (p=.012), and the fat infiltration ratio at C4 and C7 was higher (p=.023, 0.030) compared with the control. Logistic regression analysis showed that the C7-T1 angle (adjusted odds ratio [aOR]=0.592, p=.001) and fat infiltration ratio at C7 level (aOR=1.178, p=.030) were significant independent variables. CONCLUSIONS Smaller C7-T1 lordotic angle and severe muscle degeneration at C7 level were independent characteristics of patients with cervical imbalance.
Journal of Clinical Neuroscience | 2018
Koji Tamai; Zorica Buser; Christopher Wang; Permsak Paholpak; Hiroaki Nakamura; Jeffrey C. Wang; Patrick C. Hsieh
Studies have demonstrated superior outcomes and cost effectiveness of the spinal cord stimulation (SCS) for the treatment of chronic pain syndromes such as failed back surgery syndrome (FBSS) or complex regional pain syndrome (CRPS). However, little is known about the impact of primary diagnosis or mental disorders on the revision rate. This is the Retrospective cohort study to analyze the reintervention rates based on the primary diagnosis or comorbid mental disorder. Data of the annual trends of SCS use, revision and removal rate of SCS and additional surgical rate after removal was collected and analyzed for patients undergoing SCS between 2007 and 2015, within a private insurance billing database. Trial cases were excluded from this study. The results showed 11,029 patients received SCS implantation with percutaneous electrodes (PE, n = 7418) or surgical electrode (SE, n = 3611). There was a trend of increasing use of SCS from 2007 to 2013, followed by a decrease in last two years. There was no significant difference in the neither removal nor revision rate regardless between the patients with FBSS or CRPS at each time point. Although the removal rates within 2 years were significantly higher in the patients with anxiety disorders compared to the patients without any mental disorders (PE: p < .001, SE: 0.003), the rate of additional surgery after the removal showed no significant difference (PE: p = .532, SE: p = .262). Therefore, we concluded that the primary diagnosis and the presence of anxiety disorders did not have an impact on the additional surgical rate following SCS implantation.
European Journal of Orthopaedic Surgery and Traumatology | 2018
Permsak Paholpak; Alexander Nazareth; Yusuf A. Khan; Sameer U. Khan; Faisal Ansari; Koji Tamai; Zorica Buser; Jeffrey C. Wang
PurposeTo evaluate the kinematic change of cross-sectional area of lumbar intervertebral foramen in degenerative lumbar spondylolisthesis patients using multi-positional MRI.MethodsMulti-positional MRI was performed on 31 patients diagnosed with single or multilevel degenerative lumbar spondylolisthesis and 31 control patients without degenerative lumbar spondylolisthesis. Foraminal area (FA) was measured at the lumbar spondylolisthesis level in degenerative lumbar spondylolisthesis group and at L3-4, L4-5, and L5-S1 level in the control group. FA was measured bilaterally in neutral, flexion, and extension positions. The difference in FA between the groups was analyzed using Mann–Whitney U test, and the difference between positions within groups was analyzed using Wilcoxon signed-rank test.ResultsDegenerative lumbar spondylolisthesis group showed significantly smaller FA on both sides and on average in all three positions compared to the control group (p < 0.05 all). From neutral to flexion position, the change in FA was significantly smaller in the degenerative lumbar spondylolisthesis group than in the control group on both sides and on average (p < 0.005 all). In degenerative lumbar spondylolisthesis group, the FA showed no significant change from neutral to flexion, but showed significant change from neutral to extension (p < 0.005 all).ConclusionsFA in the degenerative lumbar spondylolisthesis group was smaller than in the control group. There was no difference in FA in degenerative lumbar spondylolisthesis group from neutral to flexion, only from neutral to extension. Patients with degenerative lumbar spondylolisthesis have a higher chance of developing foraminal stenosis.
The Spine Journal | 2017
Permsak Paholpak; Ishan Shah; Lou-Anne Acevedo-Moreno; Koji Tamai; Jeffrey C. Wang; Zorica Buser
BACKGROUND CONTEXT The thoracic spine was previously known as a relatively stable region in human spine. Several studies reported that the motion of the thoracic spine and changes in the cross-sectional area of the spinal cord changed with positions in the sagittal plane. The kinematic relationship between the thoracic disc and the space available for cord (SAC) with the positional change is still not well investigated. PURPOSE The objective of this study was to evaluate the kinematic change of the intervertebral disc and space available for the spinal cord of the thoracic spine using kinematic magnetic resonance imaging (kMRI). STUDY DESIGN This is a retrospective study. PATIENT SAMPLE The patient sample included 105 patients who underwent thoracic spine kMRI. OUTCOME MEASUREMENT Disc bulging and the SAC were evaluated from T4-T5 to T11-T12 in flexion, neutral, and extension positions. METHODS MRAnalyzer3 (TrueMRI Corporation, Bellflower, CA, USA) was used to analyze disc bulging and SAC from T4-T5 to T11-T12. The Friedman test was used to analyze the differences in disc bulging and SAC between neutral, flexion, and extension positions at each segment. The Wilcoxon signed-rank test was used for post hoc analysis for the significant levels from the Friedman test. RESULTS The mean value of the thoracic intervertebral disc area from T4-T5 to T11-T12 tended to be larger in flexion than in extension. Initial analysis with the Friedman test revealed a significant difference in disc bulging at T8-T9, T9-T10, and T11-T12 among the three positions (p<.05). Post hoc analysis showed that disc bulging was only significant at T8-T9 between flexion and extension (p<.001), at T9-T10 between neutral and flexion (0.003), and at T9-T10 between flexion and extension (p=.004). The SAC from T4-T5 to T11-T12 tended to be widest in extension and narrowest in flexion. Only T5-T6 exhibited a statistically significant difference in SAC between flexion and extension (p=.002). CONCLUSIONS The thoracic discs and the SAC from T4-T5 to T11-T12 showed kinematic changes from flexion to extension. The thoracic spinal canal tended to be narrowest in flexion and widest in the extension. Thus, kyphotic deformities could be one of the etiologies for neurogenic deterioration in patients with thoracic myelopathy.
Spine | 2017
Koji Tamai; Zorica Buser; Permsak Paholpak; Kittipong Seesumpun; Hiroaki Nakamura; Jeffrey C. Wang
European Spine Journal | 2018
Permsak Paholpak; Koji Tamai; Kyle Shoell; Kittipong Sessumpun; Zorica Buser; Jeffrey C. Wang